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2.
J Chromatogr A ; 1728: 464986, 2024 May 25.
Article in English | MEDLINE | ID: mdl-38797137

ABSTRACT

In this study, a novel at-line nanofractionation platform was established for screening SARS-CoV-2 fusion inhibitors from natural products for the first time by combining HPLC-MS/MS with high-throughput fluorescence polarization (FP) bioassay. A time-course FP bioassay in 384 well-plates was conducted in parallel with MS/MS to simultaneously obtain chemical and biological information of potential fusion inhibitors in Lonicerae Japonicae Flos (LJF) and Lianhua Qingwen capsules (LHQW). Semi-preparative liquid chromatography and orthogonal HPLC separation were employed to enrich and better identify the co-eluted components. After comprehensive evaluation and validation, 28 potential SARS-CoV-2 fusion inhibitors were screened out and identified. Several compounds at low micromolar activity were validated by in vitro inhibitory assay, molecular docking, cytotoxicity test, and pseudovirus assay. Moreover, four potential dual-target inhibitors against influenza and COVID-19 were discovered from LJF using this method, offering novel insights for the development of future pharmaceuticals targeting epidemic respiratory diseases.

3.
J Chromatogr A ; 1722: 464896, 2024 May 10.
Article in English | MEDLINE | ID: mdl-38631224

ABSTRACT

In this study, a novel magnetic bead-based ligand fishing method was developed for rapid discovery of monoterpene indoles as monoamine oxidase A inhibitors from natural products. In order to improve the screening efficiency, two different magnetic beads, i.e. amine and carboxyl terminated magnetic beads, were comprehensively compared in terms of their ability to immobilize monoamine oxidase A (MAOA), biocatalytic activity and specific adsorption rates for affinity ligands. Carboxyl terminated magnetic beads performed better for MAOA immobilization and demonstrated superior performance in ligand fishing. The MAOA immobilized magnetic beads were applied to screen novel monoamine oxidase inhibitors in an alkaloid-rich plant, Hunteria zeylanica. Twelve MAOA affinity ligands were screened out, and ten of them were identified as monoterpene indole alkaloids by HPLC-Obitrap-MS/MS. Among them, six ligands, namely geissoschizol, vobasinol, yohimbol, dihydrocorynanthenol, eburnamine and (+)-isoeburnamine which exhibited inhibitory activity against MAOA with low IC50 values. To further explore their inhibitory mechanism, enzyme kinetic analysis and molecular docking studies were conducted.


Subject(s)
Molecular Docking Simulation , Monoamine Oxidase Inhibitors , Monoamine Oxidase , Monoamine Oxidase Inhibitors/chemistry , Monoamine Oxidase Inhibitors/pharmacology , Monoamine Oxidase Inhibitors/isolation & purification , Monoamine Oxidase/metabolism , Monoamine Oxidase/chemistry , Ligands , Indoles/chemistry , Monoterpenes/chemistry , Monoterpenes/isolation & purification , Kinetics , Tandem Mass Spectrometry/methods , Chromatography, High Pressure Liquid/methods , Enzymes, Immobilized/chemistry , Enzymes, Immobilized/metabolism , Enzymes, Immobilized/antagonists & inhibitors , Humans , Plant Extracts/chemistry
4.
J Chromatogr A ; 1722: 464864, 2024 May 10.
Article in English | MEDLINE | ID: mdl-38598890

ABSTRACT

In this study, a novel piperidinium-sulfonate based zwitterionic hydrophilic monolith was prepared through thermally initiated co-polymerization of a piperidinium-sulfonate monomer 3-(4-((methacryloyloxy)methyl)-1-methylpiperidin-1-ium-1-yl)propane-1-sulfonate (MAMMPS), and a hydrophilic crosslinker N,N'-methylenebisacrylamide (MBA) using n-propanol and H2O as porogenic system. Satisfactory mechanical and chemical stabilities, good repeatability and high column efficiency (120,000 N/m) were obtained on the optimal monolith. The resulting poly(MAMMPS-co-MBA) monolith showed a typical HILIC retention behavior over an ACN content range between 5 and 95 %. Furthermore, this column exhibited good separation performance for various polar compounds. Compared to quaternary ammonium-sulfonate based zwitterionic hydrophilic monolith, i.e. poly(N,N-dimethyl-N-methacryloxyethyl-N-(3-sulfopropyl)ammonium betaine-co-MBA), the poly(MAMMPS-co-MBA) monolith displayed stronger retention and better selectivity for the tested phenolic and amine compounds at different pH conditions. Finally, this column was applied for the separation of six sulfonamide antibiotics, and the analytical characteristics of the method were evaluated in terms of precision, repeatability, limits of detection (LOD) and quantitation (LOQ). Overall, this study not only developed a novel HILIC monolithic column, but also proved the potential of piperidinium-sulfonate based zwitterionic chemistry as stationary phase, which further increased the structure diversity of zwitterionic HILIC stationary phases.


Subject(s)
Hydrophobic and Hydrophilic Interactions , Piperidines , Piperidines/isolation & purification , Piperidines/chemistry , Reproducibility of Results , Sulfonic Acids/chemistry , Chromatography, High Pressure Liquid/methods , Chromatography, Liquid/methods , Acrylamides/chemistry , Polymerization , Acetonitriles/chemistry
5.
Anal Chem ; 96(15): 5940-5950, 2024 Apr 16.
Article in English | MEDLINE | ID: mdl-38562013

ABSTRACT

Peptide-based supramolecules exhibit great potential in various fields due to their improved target recognition ability and versatile functions. However, they still suffer from numerous challenges for the biopharmaceutical analysis, including poor self-assembly ability, undesirable ligand-antibody binding rates, and formidable target binding barriers caused by ligand crowding. To tackle these issues, a "polyvalent recognition" strategy employing the CD20 mimotope peptide derivative NBD-FFVLR-GS-WPRWLEN (acting on the CDR domains of rituximab) was proposed to develop supramolecular nanofibers for target antibody recognition. These nanofibers exhibited rapid self-assembly within only 1 min and robust stability. Their binding affinity (179 nM) for rituximab surpassed that of the monomeric peptide (7 µM) by over 38-fold, highlighting that high ligand density and potential polyvalent recognition can efficiently overcome the target binding barriers of traditional supramolecules. Moreover, these nanofibers exhibited an amazing "instantaneous capture" rate (within 15 s), a high recovery (93 ± 3%), and good specificity for the target antibody. High-efficiency enrichment of rituximab was achieved from cell culture medium with good recovery and reproducibility. Intriguingly, these peptide nanofibers combined with bottom-up proteomics were successful in tracking the deamidation of asparagine 55 (from 10 to 16%) on the rituximab heavy chain after 21 day incubation in human serum. In summary, this study may open up an avenue for the development of versatile mimotope peptide supramolecules for biorecognition and bioanalysis of biopharmaceuticals.


Subject(s)
Biological Products , Nanofibers , Humans , Rituximab , Nanofibers/chemistry , Ligands , Reproducibility of Results , Peptides/chemistry
6.
Acta Pharm Sin B ; 14(4): 1772-1786, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38572096

ABSTRACT

Human monoamine oxidase B (hMAO-B) has emerged as a pivotal therapeutic target for Parkinson's disease. Due to adverse effects and shortage of commercial drugs, there is a need for novel, highly selective, and reversible hMAO-B inhibitors with good blood-brain barrier permeability. In this study, a high-throughput at-line nanofractionation screening platform was established with extracts from Chuanxiong Rhizoma, which resulted in the discovery of 75 active compounds, including phenolic acids, volatile oils, and phthalides, two of which were highly selective novel natural phthalide hMAO-B inhibitors that were potent, selective, reversible and had good blood‒brain permeability. Molecular docking and molecular dynamics simulations elucidated the inhibition mechanism. Sedanolide (IC50 = 103 nmol/L; SI = 645) and neocnidilide (IC50 = 131 nmol/L; SI = 207) demonstrated their excellent potential as hMAO-B inhibitors. They offset the limitations of deactivating enzymes associated with irreversible hMAO-B inhibitors such as rasagiline. In SH-SY5Y cell assays, sedanolide (EC50 = 0.962 µmol/L) and neocnidilide (EC50 = 1.161 µmol/L) exhibited significant neuroprotective effects, comparable to the positive drugs rasagiline (EC50 = 0.896 µmol/L) and safinamide (EC50 = 1.079 µmol/L). These findings underscore the potential of sedanolide as a novel natural hMAO-B inhibitor that warrants further development as a promising drug candidate.

7.
J Pharm Biomed Anal ; 244: 116125, 2024 Jul 15.
Article in English | MEDLINE | ID: mdl-38554553

ABSTRACT

As a pivotal enzyme that regulates dephosphorylation in cell activities and participates in the insulin signaling pathway, protein tyrosine phosphatase 1B (PTP1B) is considered to be an important target for the therapy of diabetes. In this work, a rapid and efficient inhibitor screening method of PTP1B was established based on capillary electrophoresis (CE), and used for screening and evaluating the inhibition effect of Traditional Chinese Medicine on PTP1B. Response Surface Methodology was used for optimizing the conditions of analysis. After method validation, the enzyme kinetic study and inhibition test were performed. As a result, the IC50 of PTP1B inhibitors Ⅳ and ⅩⅧ were consistent with reported values measured by a conventional method. It was found that the extracts of Astragalus membranaceus (Fisch) Bunge and Morus alba L. showed prominent inhibition on the activity of PTP1B, which were stronger than the positive controls. Meanwhile, on top of the excellent advantages of CE, the whole analysis time is less than 2 min. Thus, the results demonstrated that a fast and efficient screening method was successfully developed. This method could be a powerful tool for screening inhibitors from complex systems. It can also provide an effective basis for lead compound development in drug discovery.


Subject(s)
Drugs, Chinese Herbal , Electrophoresis, Capillary , Hypoglycemic Agents , Protein Tyrosine Phosphatase, Non-Receptor Type 1 , Humans , Astragalus propinquus/chemistry , Drugs, Chinese Herbal/pharmacology , Drugs, Chinese Herbal/chemistry , Drugs, Chinese Herbal/analysis , Electrophoresis, Capillary/methods , Enzyme Inhibitors/pharmacology , Enzyme Inhibitors/analysis , Hypoglycemic Agents/pharmacology , Kinetics , Medicine, Chinese Traditional/methods , Morus/chemistry , Protein Tyrosine Phosphatase, Non-Receptor Type 1/antagonists & inhibitors , Protein Tyrosine Phosphatase, Non-Receptor Type 1/metabolism
8.
Acta Pharm Sin B ; 14(3): 1317-1328, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38487009

ABSTRACT

Due to low immobilized ligand density, limited binding capacity, and severe interference from serum proteins, developing ideal peptide-based biomaterials for precise recognition and in vivo analysis of biopharmaceuticals remains a huge challenge. In this study, mimotope peptide modified pompon mum-like biomimetic magnetic microparticles (MMPs, 3.8 µm) that mimic the specific functionalities of CD20 on malignant B cells were developed for the first time. Benefit from the numerous ligand binding sites (Ni2+) on the pompon mum-like MMPs, these novel materials achieved ≥10 times higher peptide ligand densities (>2300 mg/g) and antibody binding capacities (1380 mg/g) compared to previous reported biomaterials. Leveraging the high specificity of the mimotope peptide, rituximab can be precisely recognized and enriched from cell culture media or serum samples. We also established an LC‒MS/MS method using the MMPs for tracking rituximab biotransformation in patient serum. Intriguingly, deamidation of Asn55 and Asn33, as well as oxidation of Met81 and Met34 were observed at the key complementarity determining regions of rituximab, which could potentially influence antibody function and require careful monitoring. Overall, these versatile biomimetic MMPs demonstrate superior recognition and enrichment capabilities for target antibodies, offering interesting possibilities for biotransformation analysis of biopharmaceuticals in patient serum.

9.
J Chromatogr A ; 1713: 464541, 2024 Jan 04.
Article in English | MEDLINE | ID: mdl-38041978

ABSTRACT

To in-depth explore the action mechanism of C-reactive protein (CRP) and precisely study its signaling pathways, it is essential to acquire high-purity CRP while preserving its intact structure and functionality. In this study, we propose and fabricate a high-density 2-methacryloyloxyethyl phosphorylcholine (MPC)-modified membrane roll column (MPC-MRC) using a surface-initiated atom transfer radical polymerization (SI-ATRP) approach, which can overcome these limitations (long incubation time and low adsorption capacity) of conventional enrichment materials. The MPC-MRC incorporates a high-density 2-hydroxyethyl methacrylate polymer brush to prevent non-specific protein adsorption and multiple MPC polymer brush layers for high-performance enrichment of CRP in the company of calcium ions. Furthermore, the MPC-MRC exhibits high permeability, hydrophilicity, and mechanical strength. Compared to previous technologies, this novel material demonstrates significantly higher CRP binding capacity (310.3 mg/g), shorter processing time (only 15 min), and lower cost (only 12 USD/column). Notably, the MPC-MRC enables fast and effective purification of CRP from both human and rat serum, exhibiting good selectivity, recovery (> 91.3 %), and purity (> 95.2 %). Thus, this proposed purification approach based on MPC-MRC holds great potential for target protein enrichment from complex samples, as well as facilitating in-depth studies of its biological functions.


Subject(s)
Biomimetics , C-Reactive Protein , Animals , Humans , Rats , C-Reactive Protein/chemistry , Methacrylates/chemistry , Polymers/chemistry , Phosphorylcholine/chemistry , Surface Properties , Adsorption
10.
Anal Sci ; 40(1): 85-91, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37843729

ABSTRACT

Rapid and effective separation of nucleotides (NTs) and their derivatives is crucial for studying their physiological functions. In this work, we comprehensively evaluated the separation ability of a zwitterionic hydrophilic monolith, i.e., poly(N,N-dimethyl-N-(3-methacrylamidopropyl)-N-(3-sulfopropyl)ammonium betaine-co-N,N'-methylenebisacrylamide) (poly(SPP-co-MBA)) for NTs analysis, including its selectivity, chemical stability under extremely basic condition and compatibility with hydrophilic interaction liquid chromatography (HILIC) coupled with mass spectrometry (HILIC-MS). The poly(SPP-co-MBA) monolith exhibited excellent chemical stability, as evidenced by the low relative standard deviation of retention time (0.16-1.05%) after 4000 consecutive injections over one month under strong alkaline elution condition (pH 10). After optimizing the separation conditions, including buffer pH and concentration, organic solvent content and column temperature, four nucleoside triphosphates, five nucleoside diphosphates and five nucleoside monophosphates were baseline separated within 7 min. Additionally, the mixtures containing one nucleoside and its corresponding mono-, di-, and triphosphates were baseline separated within only 3 min, respectively. It is good HILIC-MS compatibility was also confirmed by the satisfactory peak shape and high response of nine NTs. Overall, the proposed poly(SPP-co-MBA) monolith exhibited good mechanical stability and compatibility of HILIC-MS, making it a promising technique for NTs analysis.


Subject(s)
Nucleosides , Nucleotides , Nucleotides/analysis , Nucleosides/analysis , Nucleosides/chemistry , Chromatography, Liquid/methods , Betaine/chemistry , Hydrophobic and Hydrophilic Interactions
11.
Analyst ; 149(1): 212-220, 2023 Dec 18.
Article in English | MEDLINE | ID: mdl-38018757

ABSTRACT

The accurate and rapid detection of specific antibodies in blood is very important for efficient diagnosis and precise treatment. Conventional methods often suffer from time-consuming operations and/or a narrow detection range. In this work, for the rapid determination of bevacizumab in plasma, a series of chimeric hairpin DNA aptamer-based probes were designed by the modification, labeling and theoretical computation of an original aptamer. Then, the dissociation constant of the modified hairpin DNA to bevacizumab was measured and screened using microscale thermophoresis. The best chimeric hairpin DNA aptamer-based probe was then selected, and a one-step platform for the rapid determination of bevacizumab was constructed. This strategy has the advantages of being simple, fast and label-free. Because of the design and screening of the hairpin DNA, as well as the optimization of the concentration and electrochemical parameters, a low detection limit of 0.37 pM (0.054 ng mL-1) with a wide linear range (1 pM-1 µM) was obtained. Finally, the rationally constructed biosensor was successfully applied to the determination of bevacizumab in spiked samples, and it showed good accuracy and precision. This method is expected to truly realize accurate and rapid detection of bevacizumab and provides a new idea for the precise treatment of diseases.


Subject(s)
Aptamers, Nucleotide , Biosensing Techniques , Bevacizumab , Biosensing Techniques/methods , DNA , DNA Probes/genetics , Limit of Detection , Electrochemical Techniques
12.
Molecules ; 28(7)2023 Mar 23.
Article in English | MEDLINE | ID: mdl-37049668

ABSTRACT

The kinetic performance of different zwitterionic hydrophilic interaction liquid chromatography polymer columns is evaluated and compared in-depth. For this purpose, two lab-made monolithic columns, synthesized with different crosslinkers, and a commercial particle packed column are considered. It is found that performance evaluation techniques, such as comparing plate height curves or fitted A-, B- and C-terms, obtained by fitting experimental plate height data to a plate height model, are complicated by the determination of a reliable characteristic length. This is due to the very different morphology of these column types, and the heterogeneity of the monolithic columns. The occurrence of a convective flow through the packed particle column further complicates the interpretation of the obtained fitting parameters, as part of the C-term is wrongfully attributed to the A-term. Therefore, the use of the kinetic plot method is suggested for the comparative evaluation of these columns, as kinetic plots do not require the determination of a characteristic length, nor rely on any fitting parameters. With the kinetic plot method, it is demonstrated that the lab-made monolithic columns outperform the packed particle column for plate counts between 10,000 and 800,000. This is attributed to the higher column efficiency of these columns, due to their small domain and skeleton sizes, and their high permeability, resulting from their high external porosity and the occasional occurrence of preferential flow paths.

13.
Anal Chim Acta ; 1246: 340892, 2023 Mar 15.
Article in English | MEDLINE | ID: mdl-36764776

ABSTRACT

Selective enrichment and analysis of therapeutic antibodies in biological fluids are crucial for the development of biopharmaceuticals. Recently, peptide-based affinity chromatography has exhibited fascinating prospects for antibody enrichment due to the high affinity and specificity of small peptides. However, the post-modification approach of peptide ligands on the material surface is complicated and time-consuming. In this study, a methacrylate modified tetrapeptide (m-EDPW) was firstly demonstrated as the affinity ligand of trastuzumab (Kd = 1.91 ± 1.81 µM). Next, the m-EDPW based affinity monolith was prepared using a facile one-step polymerization method, which could overcome the drawbacks of traditional post-modification preparation strategies. Based on the monolith as described above, a simple enrichment approach was developed under the optimal washing and elution conditions. Based on the excellent properties, such as high porosity (53.09%), weak electrostatic interaction and suitable affinity (1.00 ± 2.14 µM for anti-HER2 ADC), this novel monolith exhibited good specificity and recovery for antibodies (91.6% for trastuzumab, 98.37% for anti-HER2 ADC), and low nonspecific adsorption for human serum albumin (DBC10% = 0.5 mg/g polymer). Particularly, this material was successfully applied to enrich trastuzumab and its related antibody-drug conjugate (ADC) from different cell culture medias. The dynamic tracking analysis of ADC in the critical quality attributes (e.g., charge variants, drug to antibody ratio and subunit conjugation ratio) was also achieved by combining the enrichment approach, capillary electrophoresis or reversed phase liquid chromatography. In summary, the exploited peptide-based mimotope affinity materials showed a great potential for the application in biopharmaceutical analysis.


Subject(s)
Antineoplastic Agents , Immunoconjugates , Humans , Trastuzumab/chemistry , Peptides/chemistry , Chromatography, Reverse-Phase , Chromatography, Affinity
14.
Anal Chem ; 95(6): 3532-3543, 2023 02 14.
Article in English | MEDLINE | ID: mdl-36744576

ABSTRACT

Phospholipid-based materials exhibit great application potential in the fields of chemistry, biology, and pharmaceutical sciences. In this study, an inside-out oriented choline phosphate molecule, 2-{2-(methacryloyloxy)ethyldimethylammonium}ethyl n-butyl phosphate (MBP), was proposed and verified as a novel ligand of C-reactive protein (CRP) to enrich the functionality of these materials. Compared with phosphorylcholine (PC)-CRP interactions, the binding between MBP and CRP was not affected by the reverse position of phosphate and choline groups and even found more abundant binding sites. Thus, high-density MBP-grafted biomimetic magnetic nanomaterials (MBP-MNPs) were fabricated by reversible addition-fragmentation chain transfer polymerization based on thiol-ene click chemistry. The novel materials exhibited multifunctional applications for CRP including purification and ultrasensitive detection. On the one hand, higher specificity, recovery (90%), purity (95%), and static binding capacity (198.14 mg/g) for CRP were achieved on the novel materials in comparison with traditional PC-based materials, and the enriched CRP from patient serum can maintain its structural integrity and bioactivity. On the other hand, the CRP detection method combining G-quadruplex and thioflavin T developed with MBP-MNPs showed a lower detection limit (10 pM) and wider linear range (0.1-50 nM) than most PC-functionalized analytical platforms. Therefore, the inside-out oriented choline phosphate can not only precisely recognize CRP but also be combined with biomimetic nanomaterials to provide high application potential.


Subject(s)
C-Reactive Protein , Phosphorylcholine , Humans , Phosphorylcholine/chemistry , C-Reactive Protein/analysis , Biomimetics , Magnetic Phenomena , Phosphates
15.
J Chromatogr A ; 1691: 463817, 2023 Feb 22.
Article in English | MEDLINE | ID: mdl-36738572

ABSTRACT

In this study, an at-line nanofractionation (ANF) platform was successfully fabricated in parallel with mass spectrometry and trypsin inhibitory bioactivity assessment for rapid screening of trypsin inhibitors (TIs) from natural products for the first time. After systematic optimization, the ANF platform was applied to screen and identify TIs in the extract of a traditional Chinese herb, i.e., Cotinus coggygria Scop. The semi-preparative reverse-phase liquid chromatography was used subsequently to further simplify and enrich the insufficiently separated components. After comprehensive evaluation and validation, the ANF platform successfully identified 12 compounds as potential TIs, including 8 flavonoids and 2 organic acids. Additionally, a comparison study was conducted using two other ligand fishing approaches, i.e., capillary monolithic and magnetic beads-based trypsin-immobilized enzyme microreactors, which successfully identified 8 identical flavonoids as TIs. Importantly, the molecular docking study showed the molecular interactions between enzymes and inhibitors, thus strongly supporting the experimental results. Overall, this work has fully demonstrated the feasibility of the established ANF platform for screening TIs from Cotinus coggygria Scop., and proved its great prospects for screening bioactive components from natural products.


Subject(s)
Anacardiaceae , Biological Products , Chromatography, Reverse-Phase , Trypsin Inhibitors , Trypsin , Molecular Docking Simulation , Flavonoids/chemistry , Plant Extracts/pharmacology , Anacardiaceae/chemistry
16.
J Pharm Biomed Anal ; 223: 115166, 2023 Jan 20.
Article in English | MEDLINE | ID: mdl-36403346

ABSTRACT

Tyrosine kinases have been intensively investigated as drug targets for several decades, since they regulate many cellular processes including cell growth, differentiation, and proliferation. Indeed, the deregulation of tyrosine kinases has been confirmed to play a vital role in the pathophysiology of many diseases. During the last few years, varieties of techniques have been developed to search for new tyrosine kinase inhibitors for cancer therapy, such as traditional filtration binding assay, scintillation proximity assay and some high-throughput screening methods. In this review, we describe the basic rules, merits and demerits, and application of a number of general and advanced technologies. The purpose of this review is to provide an insight into the numerous assays to achieve the exploration of new tyrosine kinase inhibitors.


Subject(s)
Biological Assay , High-Throughput Screening Assays , Cell Cycle , Protein-Tyrosine Kinases , Protein Kinase Inhibitors/pharmacology , Tyrosine
17.
Food Chem ; 404(Pt B): 134768, 2023 Mar 15.
Article in English | MEDLINE | ID: mdl-36444090

ABSTRACT

A simple, sensitive method for pesticide distinguishment based on a colorimetric sensor array using diverse gold nanoparticles (AuNPs) at room temperature is presented in this study. Acetylcholinesterase (AChE) hydrolysis ability was influenced by different pesticides and produced different concentrations of thiocholine by hydrolyzing acetylthiocholine iodide (ATCh). Thiocholine could be easily linked to the AuNPs through an Au - S covalent bond, and AuNPs underwent aggregation, resulting in a visible color change due to alteration of surface plasmon resonance properties. Based on these results, we successfully distinguished eight pesticides (glyphosate, thiram, imidacloprid, tribenuron methyl, nicosulfuron, thifensulfuron methyl, dichlorprop, and fenoprop) utilizing five different AuNPs by colorimetric assay. The limit of detection (LOD) of this visual method for all pesticides was less than 1.5 × 10-7 M, which was more sensitive than the U.S. Environmental Protection Agency regulations specify (1.18 âˆ¼ 3.91 × 10-6 M). This method was further improved by combining a portable smartphone device with a color picking application using (color name AR) and RGB (red, green, blue) values. The method was successfully applied to pesticide residue distinguishment in real samples by linear discriminant analysis (LDA).


Subject(s)
Metal Nanoparticles , Pesticides , United States , Colorimetry , Gold , Smartphone , Acetylcholinesterase , Thiocholine
18.
J Chromatogr A ; 1687: 463693, 2023 Jan 04.
Article in English | MEDLINE | ID: mdl-36516530

ABSTRACT

In this study, an advanced at-line nanofractionation based screening platform was developed to screen potential neuraminidase inhibitors (NAIs) from Lonicera japonica Thunb by involving two parallel bioassays, for determining both oseltamivir-sensitive neuraminidase (NAS) and oseltamivir-resistant neuraminidase (NAR) inhibitory activities. 20 potential NAIs with both NAS and NAR inhibitory effects were screened from Lonicera japonica Thunb and identified by mass spectrometer, including 11 phenolic acids, 8 flavonoids and one iridoid glycoside. The proposed at-line nanofractionation based screening platform for NAIs was also used to rapidly screen nine batches of water extracts of Lonicera japonica Thunb or its similar species. Clear differences in the number and content of active components were easily observed, demonstrating that the proposed method possesses great potential for the quality control of herb medicines.


Subject(s)
Influenza A Virus, H1N1 Subtype , Lonicera , Oseltamivir/pharmacology , Neuraminidase , Antiviral Agents/pharmacology , Enzyme Inhibitors/pharmacology , Guanidines/pharmacology
19.
J Pharm Anal ; 12(5): 783-790, 2022 Oct.
Article in English | MEDLINE | ID: mdl-36320596

ABSTRACT

Zwitterionic sulfobetaine-based monolithic stationary phases have attracted increasing attention for their use in hydrophilic interaction chromatography. In this study, a novel hydrophilic polymeric monolith was fabricated through photo-initiated copolymerization of 3-(3-vinyl-1-imidazolio)-1-propanesulfonate (SBVI) with pentaerythritol triacrylate using methanol and tetrahydrofuran as the porogenic system. Notably, the duration for the preparation of this novel monolith was as little as 5 min, which was significantly shorter than that required for previously reported sulfobetaine-based monoliths prepared via conventional thermally initiated copolymerization. Moreover, these monoliths showed good morphology, permeability, porosity (62.4%), mechanical strength (over 15 MPa), column efficiency (51,230 plates/m), and reproducibility (relative standard deviations for all analytes were lower than 4.6%). Mechanistic studies indicated that strong hydrophilic and negative electrostatic interactions might be responsible for the retention of polar analytes on the zwitterionic SBVI-based monolith. In particular, the resulting monolith exhibited good anti-protein adhesion ability and low nonspecific protein adsorption. These excellent features seem to favor its application in bioanalysis. Therefore, the novel zwitterionic sulfobetaine-based monolith was successfully employed for the highly selective separation of small bioactive compounds and the efficient enrichment of N-glycopeptides from complex samples. In this study, we prepared a novel zwitterionic sulfobetaine-based monolith with good performance and developed a simpler and faster method for preparation of zwitterionic monoliths.

20.
Molecules ; 27(20)2022 Oct 15.
Article in English | MEDLINE | ID: mdl-36296516

ABSTRACT

How to rapidly and accurately screen bioactive components from complex natural products remains a major challenge. In this study, a screening platform for pancreatic lipase (PL) inhibitors was established by combining magnetic beads-based ligand fishing and high-resolution bioassay profiling. This platform was well validated using a mixture of standard compounds, i.e., (-)- epigallocatechin gallate (EGCG), luteolin and schisandrin. The dose-effect relationship of high-resolution bioassay profiling was demonstrated by the standard mixture with different concentrations for each compound. The screening of PL inhibitors from green tea extract at the concentrations of 0.2, 0.5 and 1.0 mg/mL by independent high-resolution bioassay profiling was performed. After sample pre-treatment by ligand fishing, green tea extract at the concentration of 0.2 mg/mL was specifically enriched and simplified, and consequently screened through the high-resolution bioassay profiling. As a result, three PL inhibitors, i.e., EGCG, (-)-Gallocatechin gallate (GCG) and (-)-Epicatechin gallate (ECG), were rapidly identified from the complex matrix. The established platform proved to be capable of enriching affinity binders and eliminating nonbinders in sample pre-treatment by ligand fishing, which overcame the technical challenges of high-resolution bioassay profiling in the aspects of sensitivity and resolution. Meanwhile, the high-resolution bioassay profiling possesses the ability of direct bioactive assessment, parallel structural analysis and identification after separation. The established platform allowed more accurate and rapid screening of PL inhibitors, which greatly facilitated natural product-based drug screening.


Subject(s)
Catechin , Lipase , Ligands , Luteolin/analysis , Catechin/chemistry , Plant Extracts/chemistry , Biological Assay , Tea/chemistry
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