ABSTRACT
Abstract Certolizumab pegol (CZP) is a Fab' fragment of the humanized antibody with anti-TNF-α activity that is indicated as therapy for Crohn's disease and rheumatoid arthritis. Using a BioSep-SEC-S3000 column (300 x 4.6 mm i.d., 5 µm particle size), a size exclusion liquid chromatography (SEC) method was developed. Mobile phase A consisted of 100 mM monobasic sodium phosphate and 200 mM sodium chloride (pH 7.0), while mobile phase B was ethanol (95:5, v/v), and the analysis was performed using a diode array detector (DAD) set to 214 nm and a flow rate of 0.5 ml min-1. In addition, a reversed-phase liquid chromatography (RP-LC) method based on gradient elution was developed on a Zorbax 300 SB C18 column (150 mm x 4.6 mm i.d., 3.5 µm particle size) kept at 80 °C. Mobile phase A was 0.1% (v/v) TFA in ultrapure water, and mobile phase B was a mixture of propanol, acetonitrile, ultrapure water and TFA (70 + 20 + 9.9 + 0.1, v/v) operated at a flow rate of 1.0 ml min-1, and DAD was applied at 214 nm. CZP elution was achieved with retention times of 5.6 min and 9.0 min for SEC and RP-LC, respectively.
ABSTRACT
Recombinant human interferon beta 1b (rhIFNß-1b) is clinically used to treat multiple sclerosis. A reversed-phase liquid chromatography (RP-LC) method was carried out on a Jupiter C4 column (250 mm × 4.6 mm i.d.). The mobile phase A consisted of 0.1% trifluoroacetic acid (TFA) in water, and the mobile phase B was acetonitrile with 0.1% TFA run at a flow rate of 1.0 mL/min. A size exclusion liquid chromatography (SE-LC) method was carried out on a BioSep-SEC-S 2000 column (300 mm × 7.8 mm i.d.). The mobile phase consisted of 1 mM monobasic potassium phosphate, 8 mM sodium phosphate dibasic and 200 mM sodium chloride buffer pH 7.4, run isocratically at a flow rate of 0.8 mL/min. Retention times were 31.87 and 17.78 min, and calibration curves were linear over the concentration range of 1-200 µg/mL (r2 = 0.9998) and 0.50-200 µg/mL (r2 = 0.9999), respectively, for RP-LC and SE-LC, with detection at 214 nm. Liquid chromatography (LC) methods were validated and employed in conjunction with the in vitro bioassay to assess the content/potency of rhIFNß-1b, contributing to improve the quality control and to ensure the efficacy of the biotherapeutic
Subject(s)
Biological Assay/methods , Humans , Chromatography, Reverse-Phase/methods , Interferon beta-1b/analysis , In Vitro Techniques , Biotechnology/classification , Validation StudyABSTRACT
Chemical profiling of a given herbal medicine( HM) is the prerequisite for clarifying the effective material basis and therapeutic mechanisms,and it is an important integral part of traditional Chinese medicine chemical biology( TCMCB). In current study,we aimed to propose a new strategy for fast chemical characterization of HM by using reversed phase liquid chromatography-hydrophilic interaction chromatography-predictive multiple reaction monitoring( RPLC-HILIC-p MRM),and Artemisiae Scopariae Herba was employed in this study to illustrate the entire strategy. In response to wide polarity spanning of the diverse chemical clusters in Artemisiae Scopariae Herba,RPLC and HILIC were coupled in series to retain and separate hydrophilic and hydrophobic components simultaneously by identifying the characteristics of chromatographic separation. Most of the chemical constituents in traditional Chinese medicine can be predicted by summarizing the results of chemical constituents of the same genera and introducing primary metabolites and possible substitution reaction types. Therefore,we constructed predictive ion pairs to rapidly identify the chemical constituents of Artemisiae Scopariae Herba. After comparison with control products,discussion on fragmentation pattern,and access to relevant information from literature and databases,a total of 139 components were detected and structurally annotated by matching the obtained spectral data with the information of authentic compounds. Above all,RPLC-HILIC-p MRM could be used as an eligible analytical tool for the chemical profiling of HMs.
Subject(s)
Artemisia , Chemistry , Chromatography, Reverse-Phase , Hydrophobic and Hydrophilic Interactions , Medicine, Chinese Traditional , Plants, Medicinal , ChemistryABSTRACT
A two-dimensional liquid chromatography method was developed for the analysis of rice leaves proteomics based on the coupling of hydrophilic interaction liquid chromatography-reversed-phase liquid chromatography with online tandem mass spectrometry. The influence of pH value of chromatographic mobile phase on the orthogonality of the hydrophilic interaction-reversed-phase two-dimensional liquid chromatography was evaluated by the changes of standard peptide retention. The results indicated that the better orthogonality (R2=0.34113) was achieved from the system with hydrophilic interaction columns(pH 9.3) in the first and C18columns(pH 3.3) in the second LC dimension. Coupled with multiple fraction concatenation strategy,the orthogonality of two-dimensional liquid chromatography was further evaluated in the analysis of complex rice leaf proteins. The results showed that more than 50% of the total peptides were identified less than two times, and the peptides obtained from first-dimension were well distributed across the elution window,indicating that the method showed significant orthogonality in the identification of complex rice leaf proteins. Based on the proteome discoverer software,207345 peptides belonged to 2930 protein clusters were identified.
ABSTRACT
Reversed phase liquid chromatography-tandem mass spectrometry (RPLC-MS/MS) was utilized to investigate peptide profiling and bioactivities of antler aqueous extract(AAE),digested antler aqueous extract (AED) and powder(PD). A total of 23,417 and 389 peptides,as well as 15,146 and 75 collagen peptides were identified from AAE, AED and PD, respectively. Angiotensin converting enzyme (ACE) inhibitory activity,dipeptidyl peptidase IV(DPP-IV) inhibitory activity,prolyl endopeptidase(PEP) inhibitory activity and antioxidant activity were used to evaluate the bioactivities of AAE,AED and PD,and it was found that the sequence of their bioactivities was AAE<AED<PD. All the results above proved that AED released more collagen peptides and PD possessed better biological activities. It suggests that the two edible ways of antler are complemented each other and have their own advantages.
ABSTRACT
A metabolic profiling analysis method for metabolomic studies of rice leaf was established based on HSS T3 combined with XBridge Amide Q-TOF LC/MS by comparing the influences of different extraction methods in rice leaves of metabolites. The extraction and separation of rice leaf metabolites using three different methods including methanol-chloroform-water,methanol-chloroform-ammonia,methanol-methyl tert-butyl ether -water and different chromatographic systems were compared by the numbers of peaks, identified metabolites and the metabolic pathways. The results showed that the method of methanol-chloroform-water reached the highest coverage rate of metabolites in rice leaves,and the maximum number of unique metabolites including prephenic acid, luteolin, α-linolenic acid, aconitic acid, gibberellin A12 aldehyde, isovitexin, L-Glutamate were detected. Metabolites with different polarity in rice leaf could be detected by HSS T3 and XBridge Amide. A total of 16 kinds of organic acids, 17 kinds of nucleotides, 21 kinds of amino acids, 66 kinds of fatty acids,11 kinds of phospholipids and 7 kinds of sphingolipids were identified. XBridge Amide had an absolute advantage in detecting phospholipids and sphingolipids. The metabolic pathways involved purine metabolism, pyrimidine metabolism, tricarboxylic acid cycle, arginine metabolism, fatty acid metabolism, phospholipid metabolism, sphingolipid metabolism, phenylalanine metabolism and vitamin B2 synthesis. It showed certain complementarity between the two columns in identifying metabolites and involved the metabolic pathways. The established method is expected to be useful for the metabolomic studies of rice.
ABSTRACT
A rapid,sensitive,and robust reversed-phase liquid chromatography with tandem mass spectrometrymethod was developed and validated for the determination of total and unbound ceritinib,a secondgenerationALK inhibitor,in patient plasma and brain tumor tissue samples.Sample preparation involvedsimple protein precipitation with acetonitrile.Chromatographic separation was achieved on a Waters ACQUITYUPLC BEH C18 column using a 4-min gradient elution consisting of mobile phase A(0.1% formic acidinwater)andmobile phase B(0.1% formic acid in acetonitrile),at a flow rate of 0.4 mL/min.Ceritinib and theinternal standard([13C6]ceritinib)were monitored using multiple reaction monitoring mode under positiveelectrospray ionization.The lower limit of quantitation(LLOQ)was 1 nM of ceritinib in plasma.The calibrationcurve was linear over ceritinib concentration range of 1–2000 nM in plasma.The intra-and interdayprecision and accuracy were within the generally accepted criteria for bioanalytical method(<15%).The method was successfully applied to assess ceritinib brain tumor penetration,as assessed by the unbounddrug brain concentration to unbound drug plasma concentration ratio,in patients with brain tumors.
ABSTRACT
The objective of current study was to develop a validated specific stability indicating reversed-phase liquid chromatographic method for the quantitative determination of desvenlafaxine in bulk sample and pharmaceutical dosage form in the presence of degradation products.Forced degradation studies were performed on bulk sample of desvenlafaxine as per ICH prescribed stress conditions using acid,base,oxidative and photolytic degradation to show the stability indicating power of the method.Significant degradation was observed under acidic stress condition and the degradation product formed was identified by LC-MS and a degradation pathway for drug has been proposed.Successful separation of drug from degradation products formed under stress conditions was achieved on a SymmetryShield column C18 (5 μm,250 mm × 4.6 mm,i.d.) using the mobile phase consisting of a mixture of 0.2％ (v/v) triethylamine in ammonium acetate (0.05 M; pH 6.5) and methanol using isocratic gradient.
ABSTRACT
Atomic layer deposition has been employed for postsynthesis treatment of octadecyl bonded silica (ODS) as a typical reversed-phase stationary phase for high performance liquid chromatography (HPLC) ,in an effort to alleviate peak tailing for basic compounds. With hexamethyldisilazane( HMDS) as an endcapping agent,the ODS packing materials were heated to 250℃,and maintained at that temperature for 6 h,affording packing materials which are highly inert to basic compounds. Chromatographic performance in terms of retention factor and tailing factor of the resulting phases was evaluated using phenol/pyridine and naphthalene/ami-triptyline pairs as probes. The results were compared with those for the same packing treated by liquid phase method and for the commercial products including Zorbax SB-C_(18) and Kromasil C_(18). The separation characteristics of the ODS phase obtained by atomic layer deposition appear to be superior to that by liquid phase method and,comparable with or even better than the commercial products studied. Being solvent-free process amenable to mass production,the described method provides an economical and eco-friendly approach to manufacturing HPLC packing materials on industrial scale.