In vivo determination of the bioavailability of folic acid through the utilization of the PBPK model in conjunction with UPLC.

This paper employed a physiologically based pharmacokinetic model (PBPK) to investigate the transformations of folic acid and its metabolites in vivo. Additionally, an ultra-performance liquid chromatography (UPLC) method was developed to accurately measure the body's retention rate and conversion rate of folic acid, tetrahydrofolate, and 5-methyltetrahydrofolate. Furthermore, the bioavailability of folic acid in the body was assessed by combining this method with an evaluation technique for animal models. The study found that the gastric metabolism time was 2 h, while the small intestinal metabolism duration was 4 h. The maximum conversion rate was observed in plasma and liver after 6 h, and in the brain after 8 h. This serves as a framework for creating a model to assess the bioavailability of folic acid in living organisms, to enhance the safety and efficacy of folic acid intake.

[Qualitative and semiquantitative analyses of the chemical components of the seed coat and kernel of Ziziphi Spinosae Semen].

Ziziphi Spinosae Semen refers to the dried seed of Ziziphus jujuba Mill. var. spinosa (Bunge) Hu ex H. F. Chou. The seed is composed of a reddish brown coat and a yellow kernel. A comparative study was conducted to investigate differences in the chemical composition and their relative contents between the seed coat and kernel of Ziziphi Spinosae Semen. First, the chemical compounds found in the seed coat and kernel were characterized and identified using ultra performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF/MS). The analytical results tentatively identified 57 chemical compounds based on reference-compound comparison, literature retrieval, and chemical-database (e. g., MassBank) searches; these compounds included 14 triterpenes, 23 flavonoids, 7 alkaloids, 6 carboxylic acids, and 7 other types of compounds. The mass error of the identified compounds was within the mass deviation range of 5×10-6 (5 ppm). Next, two methods of multivariate statistical analysis, namely, principal component analysis (PCA) and orthogonal partial least squares-discriminant analysis (OPLS-DA), were used to compare the differential compounds between the two seed parts. A total of 17 differential compounds were screened out via OPLS-DA based on a variable importance in projection (VIP) value of >5. The results revealed that betulinic acid, betulonic acid, alphitolic acid, and jujuboside Ⅰ mainly existed in the seed coat whereas the 13 other compounds, such as spinosin, jujuboside A, and 6‴-feruloylspinosin, mainly existed in the seed kernel. Therefore, these 17 differential compounds can be used to distinguish between the two seed parts. Finally, a semiquantitative method was established using UPLC and a charged aerosol detector (CAD) with inverse gradient compensation in the mobile phase. Six representative compounds with different types were selected to examine the CAD response consistency: magnoflorine (alkaloid), spinosin (flavone), 6‴-feruloylspinosin (flavone), jujuboside A (triterpenoid saponin), jujuboside B (triterpenoid saponin), and betulinic acid (triterpenoid acid). The results showed that the relative standard deviation (RSD) of the average response factors at different levels of these six compounds was 7.04% and that their response intensities were similar. Moreover, each compound in the fingerprint demonstrated good response consistency, and the peak areas obtained directly reflected the contents of each compound. Based on the semiquantitative fingerprints obtained, betulinic acid and oleic acid were considered the main components of the seed coat. The betulinic acid content in the seed coat was approximately 7 times higher than that in the seed kernel. Spinosin, jujuboside A, linoleic acid, betulinic acid, and oleic acid were the main components of the seed kernel. The spinosin content in the seed kernel was 18 times higher than that in the seed coat. In addition, the jujuboside A content in the seed kernel was 24 times higher than that in the seed coat. The proposed method can accurately determine the main components and compare the relative contents of these components in different seed parts. In summary, this study identified the differences in chemical components between the seed coat and kernel of Ziziphi Spinosae Semen and clarified the main components and their relative contents in these parts. The findings can not only provide a basis for the identification of chemical compounds and quality research on different parts of Ziziphi Spinosae Semen but also promote the development and utilization of this traditional Chinese medicine.

Evaluation of In Vivo Folic Acid Bioavailability in Different Mouse Strains Using Enzymatic Digestion Combined with Ultra Performance Liquid Chromatography.

By analyzing the folic acid content of various mouse strains through the use of in vivo studies, this study sought to determine whether folic acid bioavailability varies between hosts. In order to examine the stability of folic acid in the gastrointestinal tract, the rate at which it enters the blood, its retention in the organs, and its entry into the brain, folic acid was gavaged for 10 days into male and female mice of the following four strains: C57BL/6, BALB/c, ICR, and Kunming. Folic acid was extracted from eight groups of mice via solid phase extraction and triple enzyme extraction; the folic acid was subsequently quantified by ultraperformance liquid chromatography. In contrast to the other groups, female C57BL/6 mice exhibited substantially greater bioavailability as well as variations in organ retention and blood entry rates, as indicated by the experimental findings. This finding indicated that using female C57BL/6 mice to evaluate the bioavailability of folic acid is more effective.

[Chemical diversity of dissolved organic matter revealed by ultra performance liquid chromatography-Fourier transform ion cyclotron resonance mass spectrometry].

Dissolved organic matter (DOM) is a highly complex and heterogeneous mixture that exists in various environments, including rivers, oceans, soils, and atmospheric aerosols. DOM plays a crucial role in biogeochemical cycles and significantly influences the environment by regulating water quality, changing the climate, and transporting pollutants. Therefore, clarifying the detailed molecular composition of DOM is essential to obtain a better understanding of its physical and chemical properties, thereby enabling further elucidation of its biogeochemical behavior. In this study, Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) combined with quadrupole detection (QPD) was used to conduct the online ultra performance liquid chromatography (UPLC)-MS analysis of DOM in water, aerosol, and soil samples collected in Tianjin, China. The samples were extracted with pure water and filtered through a glass fiber membrane (0.45 µm). The DOM in the samples was then enriched by solid-phase extraction (SPE) and redissolved in water-acetonitrile (1∶1, v/v) at mass concentration of 200 mg/L for the LC-MS experiments. The mobile phases used for UPLC were water containing 0.1% (v/v) formic acid (A) and acetonitrile containing 0.1% (v/v) formic acid (B). The gradient elution procedure was as follows: 0-5 min, 0B; 5-11 min, 0B-95%B; 11-25 min, 95%B; 25-28 min, 95%B-0B; 28-30 min, 0B. The flow rate was 0.1 mL/min, and the injection volume was 10 µL. The UV wavelength was set at 274 nm. MS detection was performed in negative electrospray ionization (ESI(-)) mode with a capillary voltage of 5.0 kV, and the MS data were collected in broadband (m/z 150-1000) and QPD modes. The transient data size was set to 2M, the free induction decay signal length was 0.74 s, and the ion accumulation time was 0.030 s. Four chromatographic peaks were observed in the chromatograms. The first peak was identified as salt adduct compounds containing sodium formate. The three other peaks contained complex components, such as oxygen-rich, unsaturated tannin-like compounds, as well as low-oxygen, highly saturated lignin-like and protein/amino-like compounds. UPLC-FT-ICR MS was suitable for assigning the detailed elemental compositions of the DOM samples. UPLC effectively improved the ionization efficiency of difficult-to-ionize compounds and enhanced the detection accuracy of MS. Indeed, MS peaks with a mass difference of as small as 3.4 mDa were well identified. A total of 12027, 15593, and 8029 peaks in the mass spectra of the water, aerosol, and soil samples, respectively, were assigned to known elemental formulae. Peaks Ⅱ and Ⅲ were hydrophilic components mainly including CHNO and CHO compounds. Compared with peak Ⅱ, peak Ⅲ exhibited a significant increase in CHNOS and CHOS, indicating that UPLC exerted a certain separation effect on these compounds. Furthermore, the aerosol samples contained a higher concentration of sulfur-containing compounds than the water and soil samples, primarily because of the abundance of organic sulfates present in atmospheric and cloud water. Data processing and graphic visualization revealed that the unique components in the water samples mainly appeared in the area of 0.1

Characterization of pneumococcal serotype 7F in vaccine conjugation.

Streptococcus pneumoniae is a highly invasive bacterial pathogen that can cause a range of illnesses. Pneumococcal capsular polysaccharides (CPS) are the main virulence factors that causes invasive pneumococcal disease (IPD). Pneumococcal CPS serotype 7F along with a few other serotypes is more invasive and likely to cause IPD. Therefore, 7F is a target for pneumococcal vaccine development, and is included in the two recently approved multi-valent pneumococcal conjugated vaccines, i.e. VAXNEUVANCE and PREVNAR 20.To support process and development of our 15-valent pneumococcal conjugated vaccine (PCV15), chromatographic methods have been developed for 7F polysaccharide and conjugate characterization. A size-exclusion chromatography (SEC) method with UV, light scattering and refractive index detections was employed for concentration, size and conformation analysis. A reversed-phase ultra-performance liquid chromatography (RP-UPLC) method was used for analysis of conjugate monosaccharide composition and degree of conjugation. The collective information obtained by these chromatographic analysis provided insights into the pneumococcal conjugate and conjugation process.

[Determination of four aflatoxins in feeds by high throughput automated immunoaffinity magnetic beads purification-ultra performance liquid chromatography].

Aflatoxin (AFT) is an extremely toxic and highly toxic carcinogenic substance. This is particularly problematic due to the risk of aflatoxin contamination in raw feed materials and products during production, transportation, and storage. In this study, immunoaffinity magnetic beads (IMBs) were prepared for the purification of four aflatoxins (aflatoxin B1 (AFB1), aflatoxin B2 (AFB2), aflatoxin G1 (AFG1) and aflatoxin G2 (AFG2)). The aflatoxin contents were then determined rapidly and accurately using ultra performance liquid chromatography (UPLC). More specifically, the coupling ratio of magnetic beads (MBs) to the aflatoxin monoclonal antibody was initially optimized, wherein an MB volume of 1 mL and an antibody content of 2.0 mg was found to meet the purification requirements of this method. The magnetic properties of the MBs and the IMBs were then investigated using a vibrating sample magnetometer (VSM) at room temperature. As a result, the maximum saturation super magnetizations of the MBs and the IMBs were determined to be 28.61 and 23.22 emu/g, respectively, indicating that the saturation magnetization intensity of the IMBs was reduced by coupling with a non-magnetic antibody. However, the saturation magnetization intensity remained sufficiently high to permit magnetic separation from the solution. In addition, the appearance of the IMBs was examined using a biomicroscope, and it was clear that the magnetic cores were wrapped in agarose gel. Furthermore, the reaction time between the IMBs and the aflatoxins was investigated, and the optimal reaction time for meeting the purification requirements was determined to be 2 min. The stability of the IMBs was then evaluated under refrigerated storage conditions at 4 ℃. It was found that the prepared IMBs maintained a high aflatoxin enrichment capacity for at least eight months. Through the examination of three different extraction solutions, a mixture of acetonitrile and water (70∶30, v/v) was found to be optimal for the extraction of aflatoxins from the feed samples. Moreover, five sample dilutions and purification effects were also examined, and phosphate-buffered saline (containing 0.5% Tween-20) was selected as the preferred sample dilutant. With the optimized conditions, the effectiveness of using IMB for the purification of different feed samples was investigated. The resulting UPLC chromatogram showed no spurious peaks close to the target peaks, demonstrating a good purification performance. Following matrix spiking (5, 20, and 40 µg/kg, calculated based on AFB1) of the four feed samples (i. e., soybean meal, distillers dried grains with solubles, pig feed, and chicken feed), the spiked recoveries of the four aflatoxins ranged from 91.1% to 119.4% with a relative standard deviation (RSD) of <6.9%. In addition, the inter-day precision was 4.5% to 7.5%, and the method exhibited a good reproducibility. Subsequently, the developed method was used to detect AFB1 using reference materials. The test value was 18.6 µg/kg with an accuracy of 110.3%, thereby constituting satisfactory results. Upon testing 21 randomly purchased feed samples using this method, four of these samples contained AFB1, and the test results obtained using the developed method and stable isotope dilution LC-MS/MS were comparable. It was therefore apparent that the IMB purification method combined with UPLC analysis exhibited a good accuracy for aflatoxin determination. Thus, an automatic purification system was established to facilitate the operation and use of IMBs. This system was able to purify 24 samples simultaneously in 30 min. An IMB purification kit for was also designed and produced for aflatoxin detection in feed samples. The kit contained the sample dilutant, IMBs, the washing solution, and the eluent. After extraction of the feed sample, the extraction solution was added to the sample wells provided in the kit, and the purification system automatically completed the steps of aflatoxin enrichment, impurity washing, and elution of the target toxin. It should be noted that the purification process does not require the operator to manually add the solution, thereby simplifying operation. Overall, the purification method established in this study achieved the high-throughput and automatic purification of the four aflatoxins in feed samples.

[Simultaneous determination of five indole/indazole amide-based synthetic cannabinoids in electronic cigarette oil by ultra performance liquid chromatography].

Synthetic cannabinoids (SCs), which are considered some of the most widely abused new psychoactive substances available today, are much more potent than natural cannabis and display greater efficacy. New SCs can be developed by adding substituents such as halogen, alkyl, or alkoxy groups to one of the aromatic ring systems, or by changing the length of the alkyl chain. Following the emergence of the so-called first-generation SCs, further developments have led to eighth-generation indole/indazole amide-based SCs. Given that all SCs were listed as controlled substances on July 1, 2021, the technologies used to detect these substances must be quickly improved. Due to the sheer number of SCs, the chemical diversity and the fast update speed, it is challenging to determine and identify the new SCs. In recent years, several types of indole/indazole amide-based SCs have been seized, but systematic research on these compounds remains limited. Therefore, developing rapid, sensitive, and accurate quantitative methods to determine new SCs are of great importance. Compared with high performance liquid chromatography (HPLC), ultra performance liquid chromatography (UPLC) shows higher resolution, better separation efficiency, and faster analysis speeds; thus, it can meet the demand for the quantitative analysis of indole/indazole amide-based SCs in seized materials. In this study, a UPLC method was developed for the simultaneous determination of five indole/indazole amide-based SCs, including N-(1-amino-3,3-dimethyl-1-oxobutan-2-yl)-1-butyl-1H-indazole-3-carboxamide (ADB-BUTINACA), methyl 2-(1-(4-fluorobutyl)-1H-indole-3-carboxamido)-3,3-dimethylbutanoate (4F-MDMB-BUTICA), N-(1-methoxy-3,3-dimethyl-1-oxobutan-2-yl)-1-(5-fluoropentyl)-1H-indole-3-carboxamide (5F-MDMB-PICA), methyl 3,3-dimethyl-2-(1-(pent-4-en-1-yl)-1H-indazole-3-carboxamido)butanoate (MDMB-4en-PINACA), and N-(adamantan-1-yl)-1-(4-fluorobutyl)-1H-indazole-3-carboxamide (4F-ABUTINACA) in electronic cigarette oil; these SCs have been detected with increasing frequency in seized materials in recent years. The main factors influencing the separation and detection performance of the proposed method, including the mobile phase, elution gradient, column temperature, and detection wavelength, were optimized. The proposed method successfully quantified the five SCs in electronic cigarette oil via the external standard method. The samples were extracted using methanol, and the target analytes were separated on a Waters ACQUITY UPLC CSH C18 column (100 mm×2.1 mm, 1.7 µm) at column temperature of 35 ℃ and flow rate of 0.3 mL/min. The injection volume was 1 µL. The mobile phase consisted of acetonitrile and ultrapure water, and gradient elution was employed. The detection wavelengths were 290 and 302 nm. The five SCs were completely separated within 10 min under optimized conditions and showed good linear relationships between 1-100 mg/L, with correlation coefficients (r2) of up to 0.9999. The limits of detection (LOD) and quantification (LOQ) were 0.2 and 0.6 mg/L, respectively. Precision was determined using standard solutions of the five SCs at mass concentrations of 1, 10, and 100 mg/L. The intra-day precision (n=6) was <1.5%, and the inter-day precision (n=6) was <2.2%. Accuracy was determined by spiking electronic cigarette oil with low (2 mg/L), moderate (10 mg/L), and high (50 mg/L) levels of the five SCs, with six replicates per determination. The recoveries of the five SCs were 95.5%-101.9%, and their relative standard deviations (RSDs, n=6) were 0.2%-1.5%, with accuracies ranging from -4.5% to 1.9%. The proposed method showed good performance when applied to the analysis of real samples. It is accurate, rapid, sensitive, and effective for the determination of five indole/indazole amide-based SCs in electronic cigarette oil. Thus, it satisfies the requirements for practical determination and provides a reference for the determination of SCs with similar structures by UPLC.

Microbial degradation of organochlorine pesticide: 2,4-Dichlorophenoxyacetic acid by axenic and mixed consortium.

The presence of 2,4-dichlorophenoxyacetic acid (2,4-D), an organochlorine herbicide, in the environment has raised public concern as it poses hazard to both humans and the ecosystem. Three potential strains having the capability to degrade 2,4-D were isolated from on site agricultural soil and identified as Arthrobacter sp. SVMIICT25, Sphingomonas sp. SVMIICT11 and Stenotrophomonas sp. SVMIICT13. Over 12 days of incubation, 81-90% of 100 mg/L of 2,4-D degradation was observed at 2% inoculum. A shorter lag phase with 80% of degradation efficiency was observed within 5 days when the inoculum size was increased to 10%. Six microbial consortia were prepared by combining the isolates along with in-house strains, Bacillus sp. and Pseudomonas sp. Consortia R3 (Arthrobacter sp. + Sphingomonas sp.), operated with 10% of inoculum, showed 85-90% degradation within 4 days and 98-100% in 9 days. Further, targeted exo-metabolite analysis confirmed the presence and catabolism of intermediate 2,4-dichlorophenol and 4-chlorophenol compounds.

Analysis on Quality Attribute of Substance Benchmarks of Shentong Zhuyutang Based on Supramolecular "Imprinting Template" Theory / 中国实验方剂学杂志

ObjectiveBased on the supramolecular "imprinting template" theory， the autonomous action law of the component groups of Shentong Zhuyutang in the preparation process of medicinal materials-decoction pieces-formulas was studied to clarify the quantitative transfer law of its quality attributes. MethodUltra performance liquid chromatography（UPLC） fingerprint of Shentong Zhuyutang was established with mobile phase of 0.4% phosphoric acid aqueous solution（A）-acetonitrile（B） for gradient elution（0-2.5 min， 100%A； 2.5-6 min， 100%-96%A； 6-15 min， 96%-92%A； 15-25 min， 92%-88%A； 25-35 min， 88%-75%A； 35-50 min， 75%-65%A； 50-60 min， 65%-50%A； 60-65 min， 50%-30%A； 65-70 min， 100%A） and detection wavelength of 235 nm， and the total statistical moments， information entropy and primary feeding amount of fingerprint of medicinal materials， decoction pieces and benchmark samples were calculated. Dry extract rate of the benchmark samples， the transfer rates and the addition parameters of medicinal materials-decoction pieces-formulas were calculated. ResultSimilarities of the total statistical moments of UPLC fingerprint of 15 batches of medicinal materials and decoction pieces were>0.89， the relative standard deviations（RSDs） of information entropy of UPLC fingerprint of 12 medicinal materials and decoction pieces were<10%. RSDs of total first-order moment（MCRTT） and information entropy of Shentong Zhuyutang（medicinal materials） were 5.5% and 2.3%， while the RSDs of MCRTT and information entropy of Shentong Zhuyutang（decoction pieces） were 4.8% and 2.6%， respectively. The dry extract rate of 45 batches of Shentong Zhuyutang was 17.2%-20.2%. The transfer rate of medicinal materials to decoction pieces was within the range of data fluctuation， which was 70%-130% of the average value. The overall transfer rates of medicinal materials to decoction pieces and decoction pieces to benchmark samples were 101.8% and 83.0%， respectively. ConclusionThe quality properties of Shentong Zhuyutang benchmark samples can be studied by total statistical moment analysis and primary feeding amount analysis， which can confirm the supramolecular "imprinting template" theory to a certain extent.

Metabolic profile changes of kidney aging and protective effects of Polygonatum sibiricum polysaccharides on D-galactose-induced aging mice / 数字中医药（英文）

Objective@#To investigate the metabolic trajectory of kidney aging and the effects of Polygonatum sibiricum polysaccharides (PSP) against kidney aging in D-galactose (D-gal)-induced aging mice, based on ultra-performance liquid chromatography/Q-Exactive Orbitrap mass spectrometry (UPLC-Q-Exactive MS/MS). @*Methods@#A total of 36 C57 BL/6J mice were randomly allocated to six groups: control (CON), model (MOD), PSP low-dose (PSP-L), PSP medium-dose (PSP-M), PSP high-dose (PSP-H), and positive drug ascorbic acid (VC) groups. To create models of aging mice, D-gal was intraperitoneally administered to all other groups of mice except the CON group. After modeling, the appropriate Chinese medicine [PSP-L: 150 mg/(kg·d), PSP-M: 300 mg/(kg·d), PSP-H: 600 mg/(kg·d)] or positive drug [ascorbic acid, 300 mg/(kg·d)] was administered for intervention. Key markers of renal function in urine and serum of mice in each group, such as creatinine (Crea), urea nitrogen (BUN), and uric acid (UA) levels, as well as key indicators of oxidative stress in serum and kidney, including superoxide dismutase (SOD), catalase (CAT), malondialdehyde (MDA), and glutathione peroxidase (GSH-Px) were determined to validate the successful establishment of kidney aging models and to estimate the effects of PSP. Hematoxylin and eosin (HE), periodic acid Schiff (PAS), and β-galactosidase staining were used to assess the renal pathological changes. The metabolic profiles of serum, kidney, and urine samples from CON, MOD, and PSP-H groups were analyzed by UPLC-Q-Exactive MS/MS, and pattern recognition methods were used to outline the metabolic trajectory of kidney aging and to identify the characteristic metabolites. @*Results@#Age-related alterations in renal histopathology and impaired renal function in mice were also associated with oxidative stress indicators. Following the injection of PSP [PSP-H: 600 mg/(kg·d)], the pathological indices associated with aging were adjusted to normal levels, renal function and oxidative stress were improved in aging mice, and renal pathological damage was markedly improved. Meanwhile, the potential biomarkers were identified by UPLC-Q-Exactive MS/MS analysis and were further analyzed to form related metabolic pathways, with P < 0.05 as a threshold. The results showed that purine, sphingolipid, glycerophospholipid, tryptophan, and riboflavin metabolisms were the main metabolic pathways associated with aging. After administration of PSP, these pathological indices returned to normal levels, and biomarkers related to the aging process, such as adenosine monophosphate (AMP), tryptophan, and 5-hydroxytryptophan, also demonstrated, to some degree, reverse regulation (promoting synthesis). @*Conclusion@#Metabolomics methods based on UPLC-Q-Exactive MS/MS and multivariate statistical analysis can be adopted to establish metabolic profiles in aging mice. PSP has been shown to protect against kidney aging by interfering with the purine, sphingolipid, glycerophospholipid, tryptophan, and riboflavin metabolisms in the kidney.

Development of Highly Sensitive Method for Sugar Determination in Herbal Medicine; Application of Monosaccharides and Oligosaccharides in Japanese Angelica Root and Rehmannia Root.

We have developed a simple and accurate method for quantifying sugars in herbal medicines, which have hitherto been difficult to quantify. Using ultra performance liquid chromatography-quadrupole-time-of-flight (UPLC-Q-TOF)-MS and two types of columns with different chemical properties, we determined the optimum conditions for separating nine sugars (fructose, galactose, glucose, mannitol, sucrose, melibiose, raffinose, manninotriose, and stachyose) commonly found in herbal medicines. Separation was completed within 10 min when an apHera NH2 HPLC column was used, although galactose and glucose could not be separated. On the other hand, the nine sugars were completely separated within 16 min when a hydrophilic interaction chromatography (HILIC)pak VG-50 2D column was used. The calibration curves obtained using those two columns gave good linearity for the sugar standards, and the coefficient of determination was 0.995 or higher. Both columns showed excellent performance with short analysis time and high sensitivity. Using our developed method, we were able to quantify sugars in galactose-free herbal medicines within 10 min and in herbal medicines containing galactose within 16 min. We revealed that our method could be used for the analysis of sugars in Angelica acutiloba and Rehmannia glutinosa roots.

[Fast screening and confirmation of 73 common prohibited compounds in cosmetics by ultra performance liquid chromatography-quadrupole-time-of-flight high resolution mass spectrometry].

A high throughput screening method based on ultra performance liquid chromatography-quadrupole-time-of-flight high resolution mass spectrometry (UPLC-Q-TOF HRMS) was developed for the simultaneous and rapid confirmation of 73 prohibited compounds in cosmetics. The sample was dispersed in a saturated sodium chloride solution and ultrasonically extracted using acetonitrile containing 0.2% (v/v) formic acid. The resultant solution was centrifuged and then cleaned using dispersive solid phase extraction using a primary secondary amine (PSA) sorbent. The purified solution was centrifuged, and the supernatant was filtered through a 0.22 µm membrane before determination. The optimal pretreatment method was determined by comparing the recovery rates obtained using different extraction solvents and different amounts of purifying agents. The chromatographic separation conditions and mass spectrometry scanning mode were also optimized. Chromatographic separation was performed on an Acquity UPLC HSS T3 column (100 mm×2.1 mm, 1.8 µm) with gradient elution using 0.1% (v/v) formic acid aqueous solution and methanol as mobile phases. The eluent from the column was further detected using Q-TOF HRMS with the high resolution multiple reaction monitoring (MRM HR) scanning mode. Retention time, precise mass of parent ion, isotope abundance ratio, and precise mass of fragment ions were the parameters considered for rapid untargeted screening and confirmation. The matrix effects of water- and cream-based cosmetics were investigated. The matrix effects could be addressed using the matrix matched standard curve method. The correlation coefficients for the 73 prohibited compounds were all >0.99 in the corresponding linear concentration range. The limits of detection (LODs) were in the range of 5-150 µg/kg, and the limits of quantification (LOQs) were in the range of 15-450 µg/kg. Average recoveries were in the range of 60.3%-130.3% at three spiked levels, and the intra-day and inter-day precisions were 0.8%-10.0% (n=6) and 1.1%-15.0% (n=3), respectively. A total of 692 cosmetics samples were screened; 16 positive samples were detected, namely, sulfamethoxazole, meprednisone, lincomycin, 4-acetamidophenol, trimethoprim, alfacalcidol, betamethasone 17-valerate, brimonidine, chloramphenicol, chlorpheniramine, clobetasol propionate, crotamiton, econazole, ketoconazole, prednisone 21-acetate, and prednisone, with content in the range of 0.5-1136.1 mg/kg. The optimized method is accurate, fast, and simple, and it is suitable for the routine detection and rapid screening of common prohibited compounds in cosmetics. In addition, a screening and confirmation library was established for the 650 prohibited compounds using SCIEX OS and Library View software, using information-dependent acquisition (IDA)-MS/MS mode for MS data acquisition. The database contains multiple types of information, including formulas, theoretical exact mass, retention time, precise mass of parent ion, isotope abundance ratio, and fragment ion distribution. The library can be used for the simultaneous and rapid confirmation of prohibited compounds in cosmetics.

[Determination of 19 illegally added chemical ingredients in hair loss prevention cosmetics by ultra-performance liquid chromatography-quadrupole-time of flight mass spectrometry].

Cosmetic products for hair loss prevention are often mixed with prohibited substances such as hormones, antibiotics, and forbidden pharmacologically active substances. Although drugs increase the efficacy of cosmetic products, they cause skin irritation and allergic reactions, upon long-term exposure. Given the increasing number of hair loss prevention cosmetics on the market, the need to guarantee product safety calls for efficient and reliable methods to identify illegal ingredients in these products. Chromatography combined with high-resolution mass spectrometry offers the advantages of high resolution and high throughout, thus being a powerful technique for simultaneously detecting illegal ingredients in cosmetics. In this study, an ultra-performance liquid chromatography-quadrupole-time of flight mass spectrometry (UPLC-Q-TOF-MS) method for detecting 19 illegal chemical components was established. Combined with the scientific database, a screening platform for hair loss prevention cosmetics was constructed. The effect of extraction solvent was investigated. The chromatographic and mass spectrometry conditions were optimized. Under the optimal conditions, separation was achieved within 20 min on an ACQUITY UPLC BEH C18 column (100 mm×2.1 mm, 1.7 µm). Acetonitrile and 2 mmol/L ammonium formate solution containing 0.05% formic acid were used as mobile phases for gradient elution. The 19 compounds were detected by positive ion electrospray ionization (ESI) in the MSE mode. The chromatographic retention time, precursor ions, product ions of the target analytes, and abundance ratio were collected to construct a screening database with UNIFI software. The 19 compounds were well separated, with good linearity. The limits of detection (LODs) and limits of quantification (LOQs) were 0.025-0.05 µg/g and 0.075-0.15 µg/g, respectively. Hair lotion and shampoo, which are commonly marketed as hair loss prevention cosmetics, were selected as the respective matrices for the recovery experiment. The average recoveries of the 19 compounds ranged from 68.6% to 118.6%, and the relative standard deviations (RSDs) were 0.3%-10.3%. Then, 77 batches of cosmetic samples were detected and screened under the same conditions. The TOF-MS information, including the retention time, ion addition mode, mass-to-charge ratio of the parent ions and fragment ions, as well as the abundance ratio, were compared between the cosmetic samples and the standard MS information with UNIFI software. Finally, two batches of samples that were illegally adulterated with minoxidil and finasteride were identified. The ESI fragmentation pathway of the product ions from minoxidil was also proposed. The matrix matching external standard method was used to determine the amounts of minoxidil and finasteride in the two batches of hair lotion, and they were as high as 60 mg/g and 0.31 mg/g, respectively. This result revealed that multiple chemical components were simultaneously added to hair loss prevention cosmetics. Furthermore, the amount of the illegally added drug was very high, indicating high safety risk for consumers using such cosmetics. The present method has the advantages of simple operation, high sensitivity, and good reproducibility. It can be used for rapid screening and simultaneous quantitative analysis of various illegal chemicals in hair loss prevention cosmetics.

[Analysis of glycan ratio of Chinese hamster ovary cell-cetuximab antigen-binding segment via rapid enzyme digestion with endo-ß-N-acetylglucosaminidase F].

The N-glycosylation of proteins is a typical post-translational modification. Compared with other monoclonal antibodies, N-glycosylation modification in cetuximab is more complicated. Because cetuximab contains two N-glycosylation sites, one is located on the antigen-binding fragment (Fab) and the other is on the crystallizable fragment (Fc) of the heavy chain (HC). Among the two, the glycosylation of the Fab segment is more complicated. As this segment is located in the hypervariable region (VH), it may affect the affinity of the antibody antigen and cause other issues. Therefore, it is necessary to study glycosylation modification at this site. This modification is particularly challenging, necessitating the development of specific glycan cutting technology and a stable glycan ratio analysis method. In this study, cetuximab expressed in Chinese hamster ovary (CHO) cell was used as the experimental research object. Based on the digestion with endo-ß-N-acetylglucosaminidase F2 (Endo F2), an experimental method was developed that can quickly release Fab glycans. Qualitative and glycan ratio analyses were carried out by ultra performance liquid chromatography-high resolution mass spectrometry (UPLC-HRMS). The test was divided into two steps: in the first step, a non-denaturing (native state) glycosidase excision test was performed on the CHO-cetuximab drug substance. The drug substance was diluted to 1.0 mg/mL by adding ultrapure water, following which 1.0 µL of Endo F2 was directly added to 100 µL of the drug substance for enzyme digestion at 37 ℃. Through HRMS, the data were deconvoluted to obtain the accurate mass of the drug substance. The results showed that when the digestion time of Endo F2 was 5 min, the glycans in the Fab segment could be completely removed, whereas those in the Fc segment were not affected. Rapid enzyme cutting of the Fab glycans was realized; simultaneously, it was concluded that this method was also very specific for the removal of Fab glycans. In the second step, an accurate ratio analysis test was performed on Fab glycans excised from CHO-cetuximab. The released Fab glycans were precipitated with ice ethanol, the supernatant was centrifuged and spin-dried, and then labeled with para-aminobenzyl (2-AB). 2-AB labeling could make glycans have fluorescent detectable signals, and after reconstitution in 70% acetonitrile aqueous solution, was detected by UPLC coupled with a fluorescence detector (FLR). Good chromatographic peak separation was obtained using a hydrophilic interaction chromatography (HILIC) column. Thus, the test enabled stable glycan ratio analysis. The molecular weight results for three independent Endo F2 digestion cycles for 5 min showed that the masses after digestion were similar; subsequently, glycan ratio analysis was performed based on HILIC. The results of three independent glycan ratio analysis experiments were also similar, indicating that the rapid enzyme digestion of Endo F2 followed by glycan ratio analysis after 5 min of digestion yielded good stability and reliability. Data obtained by measuring the samples produced using two different processes employed by our company showed that there were distinct differences in the glycan profiles of the two processes, especially in terms of the sialic acid glycoforms. These results prove that the method developed in this study can accurately analyze the ratio of glycans. Monitoring the antibody production process is important and meaningful for the evaluation of the process.

Analytical Lifecycle Management (ALM) and Analytical Quality by Design (AQbD) for analytical procedure development of related substances in tenofovir alafenamide fumarate tablets.

Analytical procedure development for quantifying 10 impurities in Tenofovir Alafenamide Fumarate (TAF) tablets was a challenge for analytical and formulation researchers. The aim of this paper was to develop a robust, regulatory-flexible, application-specific Ultra Performance Liquid Chromatography (UPLC) analytical procedure using the Analytical Lifecycle Management (ALM) and the Analytical Quality by Design (AQbD) for the estimation of the TAF tablets. In this work, the Analytical Target Profile (ATP) for the analytical procedure and the Critical Analytical Attributes (CAAs) were identified. Through the risk assessment studies, the high-risk analytical conditions were found, and they were screened and optimized by the Design of Experiment (DoE) to obtain the Design Space (DS) and identify the working point. The prediction intervals were used to examine the robustness of the analytical procedure. And the procedure performance qualification and the continued procedure performance verification were used to ensure routine application of analytical procedure. Finally, the 10 impurities were separated within 20 min by UPLC. The success of this study demonstrates the usefulness of using ALM and AQbD for analytical procedure development and provides a reference for the analytical procedure development for other drugs.

[Confirmation of unknown additives in enrofloxacin powder].

In order to ensure the safety of animal food and regulate the application of veterinary drugs, it is necessary to strictly monitor their content, and to constantly improve the methods used to detect non-specific, illegally added substances in veterinary drugs. A study about the screening, analysis, and confirmation of illegal additives in enrofloxacin powder (used for aquaculture) using non-targeted analysis technology was introduced. First, an enrofloxacin powder test solution under acidic conditions was prepared by adding formic acid, and an enrofloxacin powder test solution under alkaline conditions was prepared by adding sodium carbonate. An ultra-performance liquid chromatography with photodiode array detector (UPLC-PDA) was used to assay the test solutions for the presence of unknown additives. Results revealed two high-response unknown peaks in the acidified test solution, with retention times of 1.870 min and 5.122 min respectively. In the alkalized test solution, only one high-response unknown peak was found, with a retention time of 5.122 min. The ultraviolet spectrum characteristic peaks at 5.122 min in acidified and alkalized test solutions were similar, but the peak area in the alkalized test solution was almost ten times that in the acidified solution. Two potential unknown substances were detected. Unknown substance 1 (1.870 min) and unknown substance 2 (5.122 min) may transform under acidic or alkaline conditions. Ultra-performance liquid chromatography-time of flight high resolution mass spectrometry (UPLC-TOF-HRMS) was used to analyze the unknown compounds in more detail. The acidified and alkalized test solutions were detected in the positive and negative ion modes of mass spectrometry, respectively. Accurate mass of the precursor ion, characteristics of secondary ion fragments, and isotopic intensity ratio of the two unknown substances were collected. This information was imported into SCIEX OS software. The molecular formula of the parent ion of unknown substance 2 was found to fit to C11H8O2, and its secondary fragment structure may contain a benzene ring and two carbonyl groups, with a propylene structure connected to them through ring formation. From this, unknown substance 2 was presumed to be a menadione. The molecular ion peak of unknown substance 1 was found to fit to C11H9O5S-, only HSO3- was collected in the secondary fragments, and the missing part was consistent with unknown substance 2. Considering the most common derivatives of menadione, unknown substance 1 can be proposed to be menadione sodium bisulfite. Finally, we used menadione and menadione sodium bisulfite as reference substances in a comparative study. The same treatment method was used to prepare menadione, menadione sodium bisulfite reference solution, and enrofloxacin powder test solution. After UPLC-PDA detection, unknown substance 1 and menadione sodium bisulfite, unknown substance 2 and menadione, were found to have similar retention times and UV spectra. When the reference solution was added to the enrofloxacin powder test solution, the peak purity of the unknown substance did not change, and were all single peaks. UPLC-TOF-HRMS analysis revealed that the retention time of unknown substance 1 was consistent with that of sodium menadione bisulfite: compared to its accurate mass number in theory, the mass accuracy error was 1.0×10-6, and the matching degree of fragmentation information in the library was 100%. The retention time of unknown substance 2 was same as the menadione: compared to its accurate mass number in theory, the mass accuracy error was 0.6×10-6, and the matching degree of fragmentation information in the library was 99.7%. The structures of unknown substances 1 and 2 were confirmed. Menadione sodium bisulfite is known to participate in the synthesis of thrombin in the liver, and also promotes the formation of prothrombin, and accelerates coagulation. The indication of enrofloxacin powder (used for aquaculture) is the treatment of hemorrhage and sepsis in aquaculture animals such as fish and eel. The pharmacological effects of the two drugs correspond to each other, which can cause producers to take risks and add them illegally. With the strict supervision and severe restrictions on the addition of veterinary drugs, illegal additives are becoming more and more subtle. Conventional targeted analysis does not always meet the monitoring requirements. In this paper, the non-targeted analysis of unknown substances using UPLC-PDA combined with UPLC-TOF-HRMS is described in detail. The results may provide a technical reference for screening and identifying illegal additives in drugs, food, health care products, cosmetics, and pesticides.

[Determination of 18 amino acids in three different kinds of milk powder by ultra performance liquid chromatography coupled with pre-column derivatization].

In recent years, goat milk powder and camel milk powder have gained popularity among consumers. Due to their potential low allergenicity, these milk powders have become a substitute for breast milk, especially for infants, and for people with lactose intolerance. In this paper, a method was developed for the simultaneous determination of 18 amino acids (AAs), histidine (His), serine (Ser), arginine (Arg), glycine (Gly), aspartic acid (Asp) combined with asparagine (Asn), glutamic (Glu), glutamine (Gln), threonine (Thr), alanine (Ala), proline (Pro), lysine (Lys), tyrosine (Tyr), methionine (Met), valine (Val), isoleucine (Iso), leucine (Leu), and dimer of cysteine (Cys) combined with cysteine (L-Cys-Cys), phenylalanine (Phe), taurine (Tau) in milk, goat milk, and camel milk power. The aim of the research was to compare the three kinds of milk powder from the perspective of the constituent amino acids. Therefore, the amino acid compositions and contents were compared. Thus, 2.0 g of the sample was accurately weighed, added to 16 mL H2O, and mixed thoroughly. Then, 200 mg of the sample was weighed in a glass tube with a stream of nitrogen to displace oxygen. The samples were hydrolyzed in HCl for 24 h at 110 ℃. Then, the amino acids were pre-column derivatized by 6-aminoquinoline-n-hydroxysuccinimide carbamate (AQC). In precolumn derivatization combined with reverse-phase chromatography, both 2,4-dinitrofluorobenzene (DNFB) and phenylisothiocyanate (PITC) can react with primary amines and secondary amines. However, the derivatization time is approximately 1 h. In contrast, the derivatization time of AQC was greatly shortened. Derivatization led to the conversion of free amino acids into highly stable derivatives, which were separated by ultra performance liquid chromatography (UPLC) with UV detection at 260 nm and quantified by the external standard method. The samples were separated on a BEH C18 column (150 mm×2.1 mm, 1.7 µm) at a flow rate of 0.4 mL/min. The calibration curves showed good linearity, with correlation coefficients greater than 0.999. The limits of detection (LODs) and limits of quantification (LOQs) of the 18 amino acids were 1.3-2.5 (mg/100 g) and 3.9-7.5 (mg/100 g), respectively. Quality control samples of SRM 1849a were used as the reference material. The results were in accordance with the content range. The RSDs ranged from 2.04% to 3.65%. Furthermore, the developed method was successfully applied to determine the types and concentrations of amino acids in 11 samples purchased from local markets in Shanghai and online shops. Abundant amino acids were detected in the three types of milk powder. While all the milk powder samples contained 18 types of amino acids, Tau was not detected in some of the goat and camel milk powder samples. Total essential amino acids (TEAA) in total amino acids (TAA) of milk powder was the highest of all. The TEAA values of TAA in the goat and camel milk powders were similar. The developed method requires only 22 min for the separation of 18 amino acids. This method is suitable for the large-scale analysis of milk powder samples, and it demonstrates high sensitivity and accuracy for the determination and confirmation of the 18 amino acids in different types of milk powders.

The correlation between kidney volume and measured glomerular filtration rate in an Asian ADPKD population: a prospective cohort study.

BACKGROUND: Autosomal dominant polycystic kidney disease (ADPKD) is the most common hereditary kidney disorder that leads to end stage renal disease (ESRD). Cyst expansion in ADPKD is strongly associated with the decline in renal function. However, the correlation between total kidney volume (TKV) and glomerular filtration rate (GFR) at an early stage has not been well demonstrated. There is growing evidence that utilization of estimated GFR (eGFR) may induce misleading information in a population with near normal renal function. Therefore, a more accurate method is essential. METHODS: A prospective cohort of ADPKD patients was conducted with clinical data and laboratory collection. Measured GFR (mGFR) was assessed by iohexol plasma clearance method using ultra performance liquid chromatography. eGFR was calculated using the CKD-EPI equation. Kidney volumes were evaluated using MRI imaging protocol. RESULTS: Thirty two patients completed the study. The mean age was 56 years old. The mean initial mGFR was 83.8 mL/min/1.73m2. The mean change in mGFR per year was -2.99 mL/min/1.73m2/year. The mean initial height-adjusted TKV (htTKV) was 681.0 mL/m. The mean percentage change in htTKV per year (%ΔhtTKV/y) was 4.77 %/year. mGFR had a better association with clinical parameters than eGFR. Initial mGFR was significantly and inversely correlated with initial htTKV and age. The percentage change in mGFR per year was significantly and inversely correlated with the %ΔhtTKV/y and 24-hr urine albumin. The %ΔhtTKV/y was significantly correlated with initial htTKV. CONCLUSIONS: Our studies demonstrated that mGFR using iohexol is a more reliable and accurate method than eGFR for evaluating GFR changes in the early stages of ADPKD patients. There is a strong inverse correlation between kidney volume and mGFR in an Asian ADPKD population. The initial htTKV is a good predictor of kidney volume progression. The %ΔhtTKV/y is a good early surrogate marker for the decline in renal function. 24-hr urine albumin is also a good indicator for renal progression.

Comparison of Effect of Chijian and Gastrodiae Rhizoma on Regulating Immune Function and Intestinal Microflora / 中国实验方剂学杂志

Objective:To compare the contents of adenosine， gastrodin， <italic>p</italic>-hydroxybenzyl alcohol， <italic>p</italic>-hydroxybenzaldehyde， parisinin B and parisinin A in Chijian （the aerial part of <italic>Gastrodia elata</italic>） and Gastrodiae Rhizoma， and compare their effects on immune function and intestinal microflora， evaluating whether it is necessary to study and develop Chijian. Method:The contents of these six constituents were determined by ultra performance liquid chromatography （UPLC）， the mobile phase was 0.1% formic acid aqueous solution （A）-acetonitrile （B） for gradient elution （0-4 min， 0.5%B； 4-5 min， 0.5%-2%B； 5-10 min， 2%-15%B； 10-12 min， 15%-20%B； 12-15 min， 20%-95%B； 15-17 min， 95%B； 17-17.5 min， 95%-0.5%B； 17.5-20 min， 0.5%B）， the flow rate was 0.5 mL·min^-1， the detection wavelength was 270 nm. The difference of pharmacological activity of water extracts of Chijian and Gastrodiae Rhizoma was compared， the clearance index， corrected clearance index and peripheral blood were measured in mice model with low immune function induced by cyclophosphamide， B lymphocyte proliferation was determined by lymphocyte transformation test <italic>in vitro</italic>， intestinal microflora was analyzed by 16S rDNA technology and bioinformatics was conducted. Result:The total contents of these six components in powder and ethanol extract of Chijian were higher than that of Gastrodiae Rhizoma， but the total contents of these six components in their water extract were similar， and the total contents of gastrodin and <italic>p</italic>-hydroxybenzyl alcohol met the requirements of the 2020 edition of <italic>Chinese Pharmacopoeia</italic>. Compared with the blank group， the clearance index of immunocompromised mice was significantly increased in the middle-dose （10 g·kg^-1） group of Chijian water extract， middle- and low-dose （10， 5 g·kg^-1） groups of Gastrodiae Rhizoma water extract （<italic>P</italic><0.05）， the levels of erythrocyte and hematocrit in peripheral blood were significantly increased in the high-dose （20 g·kg^-1） groups of water extracts of Chijian and Gastrodiae Rhizoma （<italic>P</italic><0.05， <italic>P</italic><0.01）， water extract of Gastrodiae Rhizoma with concentration of 400 g·L^-1 and the water extract of Chijian with the concentration of 100 g·L^-1 could promote the proliferation of B lymphocytes induced by lipopolysaccharide. Studies on intestinal microflora showed that compared with the blank group， at the phylum level， the water extracts of Chijian and Gastrodiae Rhizoma increased the relative abundance of Bacteroidetes and decreased the relative abundance of Firmicutes， at the genus level， they increased the relative abundance of <italic>Prevotellaceae</italic>_UCG-001 and <italic>Ruminococcaceae</italic>_UCG-005， and decreased the relative abundance of <italic>Anaerotruncus</italic>， unclassified_<italic>f</italic>_<italic>Erysipelotrichaceae</italic> and<italic> Candidatus</italic>_<italic>Stoquefichus</italic>.<italic> </italic>These intestinal bacteria were related to the immune system， cell proliferation， and metabolism regulation. Conclusion:The total contents of 6 components in the powder， the ethanol and the water extracts of Chijian are higher than or close to those of the corresponding samples of Gastrodiae Rhizoma， the pharmacological activity of Chijian water extract is similar to that of Gastrodiae Rhizoma water extract， indicating that Chijian is worthy of further research and development.

Comparison of UPLC Fingerprint and Determination of Index Components Before and After Processing of Cyperi Rhizoma Processed with Four Excipients / 中国实验方剂学杂志

Objective:To study the quality evaluation method of Cyperi Rhizoma processed with four excipients. Method:Ultra-performance liquid chromatography （UPLC） fingerprints of raw products and processed products with four excipients of Cyperi Rhizoma were established， and the changes of chemical components in the fingerprints before and after processing were compared by chemometric analysis. The mobile phase was consisted of methanol （A）-water （B） for gradient elution （0-10 min， 5%-40%A； 10-30 min， 40%-70%A； 30-40 min， 70%A） at a flow rate of 0.3 mL·min^-1. The injection volume was 3 μL， the column temperature was 35 ℃， and the detection wavelength was 280 nm. The content changes of main index components in Cyperi Rhizoma before and after processing were compared by UPLC. The mobile phase was methanol-water （75∶25） and the detection wavelength was 242 nm. Result:Processing with four excipients had a significant impact on the overall characteristics of chemical components in the fingerprint of Cyperi Rhizoma. A total of 28 characteristic peaks were identified in fingerprints of the raw and processed products. Among them， peaks 1， 2 and 4 were specific peaks of the processed products， peak 5 was characteristic peak of the raw products. Peak 2 was identified as 5-hydroxymethylfurfural， peak 24 as cyperenone and peak 27 as <italic>α</italic>-cyperone. The 5-hydroxymethylfurfural produced by the processing with four excipients came from rice vinegar， rice wine and Maillard reaction of polysaccharides in Cyperi Rhizoma. The results of determination showed that there was no significant difference in the content of cyperenone after processing， but the content of <italic>α</italic>-cyperone decreased significantly. Conclusion:In the process of Cyperi Rhizoma processed with four excipients， there are new components produced by structural transformation， which are accompanied by changes in the content of index components. In this study， the quality of raw and processed products of Cyperi Rhizoma can be rapidly and effectively evaluated from qualitative and quantitative aspects.