Chemistry-An Asian Journal
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2025
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IF 3.3
Xianghan Li,Hongyan Shu,Xinna Xu,Yalan Wang,Lingzhi Zhao,Ying Liu,Juanjuan Peng
Cathepsin S (CatS) is a lysosomal enzyme belonging to the papain family of cysteine proteases. Studies have demonstrated that CatS plays a pivotal role in antigen presentation and is associated with Alzheimer's disease, atherosclerosis, and obesity, positioning it as a potential target in related disorders. Consequently, the development of a selective and straightforward method for detecting CatS is crucial. In this study, we introduce a colorimetric approach utilizing gold nanoparticles (AuNPs) and CatS-specific peptides for the detection of CatS activity. The CatS enzyme cleavage peptides, PMGAPC or PMGAPC-NH 2 , can stabilize AuNPs in a hydrosaline solution without aggregation. Upon hydrolysis of PMGAPC or PMGAPC-NH 2 by CatS, the AuNPs aggregate with a color change from red to blue. After optimizing the size of the AuNPs and the concentration of the peptides, the limits of detection for CatS were both to be 10 nM, when PMGAPC or PMGAPC-NH 2 were used to protect the AuNPs. Therefore, this colorimetric assay, which employs peptides and AuNPs, enables not only a selective but also a simple detection of CatS, visible to the naked eye.
研究领域:
生物化学
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医学诊断
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纳米生物学
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF DAIRY SCIENCE
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2021
·
IF 4.034
Can-Peng Li,Feng Liu,Jing Zheng,Hui Zhao
ABSTRACT Chymosin is a predominant enzyme in rennet and is used in cheese production because of its excellent milk-clotting activity. Herein, we proposed a facile and label-free electrochemical method for determining chymosin activity based on a peptide-based enzyme substrate. The synthesized substrate peptide for chymosin was assembled onto the surface of the Au-deposited grassy carbon electrode. The current was proportional to chymosin activity, and thus chymosin activity could be determined. The detection ranges of chymosin activity were 2.5 to 25 U mL −1 . The detection limit of chymosin activity was 0.8 U mL −1 . The sensing platform was used to quantify chymosin activity in commercial rennet with high selectivity, excellent stability, and satisfactory reproducibility. We developed a facile, fast, and effective electrochemical assay for detecting chymosin activity, which has potential applications in cheesemaking.
研究领域:
食品科学
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生物化学
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分析化学
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF ELECTROANALYTICAL CHEMISTRY
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2025
·
IF 4.1
Wan-Yue Zhuang,Zi-Yi Wang,Xingdong Yang,Jun-Qin Qiao,Wei-Juan Zheng,Hong-Zhen Lian
Thrombin, a critical protein-based therapeutic agent, is widely used in modern medicine. Precise quantification of thrombin enzymatic activity represents a fundamental requirement for both manufacturing quality control and clinical therapeutic monitoring. Here, we developed a “signal-off” electrochemical method for the rapid detection of thrombin activity within 15 min. A thrombin-specific substrate peptide was anchored to a gold electrode via Au S bonds at its C-terminal, with an N-terminal ferrocene (Fc) tag as a redox probe. A cellulose acetate (CA) membrane was added to reduce contamination and signal loss. The detection mechanism relies on thrombin-mediated peptide cleavage, detaching the Fc-tagged fragment and generates a decreasing current proportionally to enzyme activity. The detection limit of the described method is 81.1 U/mL, with a linear response over the range of 200–1500 U/mL (R 2 = 0.9941), satisfying the quality control requirements for commercial thrombin drugs. This biosensing strategy combines operational simplicity with analytical reliability, showing significant potential for rapid and efficient assessment of thrombin biological products activity.
研究领域:
生物分析化学
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分子诊断学
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药物质量控制
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电化学生物传感器
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蛋白质功能检测
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转化医学
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产品关联
DOI
高影响因子
International Journal of Electrochemical Science
·
2023
·
IF 1.5
Qiongyu Zhang,Gang Liu,Lingbin Ou
This work reported an electrochemical method for the detection of SARS-CoV-2 major protease (Mpro). Specifically, ferrocene (Fc)-labeled peptide substrates were immobilized on the gold nanoparticles (AuNPs)-modified electrode. Cleavage of the peptides by Mpro led to the release of Fc tags and the decrease of the electrochemical signals. The analytical performance of the biosensor for analysis of Mpro was investigated. Inhibiting the activity of Mpro prevented the cleavage of the peptide substrates. The method was successfully used to evaluate the inhibition efficiency of a well-known inhibitor.
研究领域:
生物化学
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分析化学
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病毒学
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DOI
PubMed
高影响因子
ANALYTICAL CHEMISTRY
·
2021
·
IF 6.986
Qiong Hu,Luofeng Su,Zhuohua Chen,Yanyu Huang,Dongdong Qin,Li Niu
Trypsin is a key proteolytic enzyme in the digestive system and its abnormal levels are indicative of some pancreatic diseases. Taking advantage of the coenzyme-mediated electrografting of ferrocenyl polymers as a novel strategy for signal amplification, herein, a signal-on cleavage-based electrochemical biosensor is reported for the highly selective interrogation of trypsin activity at ultralow levels. The construction of the trypsin biosensor involves (i) the immobilization of peptide substrates (without free carboxyl groups) via the N-terminus, (ii) the tryptic cleavage of peptide substrates, (iii) the site-specific labeling of the reversible addition–fragmentation chain transfer (RAFT) agents, and (iv) the grafting of ferrocenyl polymers through the electro-RAFT (eRAFT) polymerization, which is mediated by potentiostatic reduction of nicotinamide adenine dinucleotide (NAD+) coenzymes. Through the NAD+-mediated eRAFT (NAD+-eRAFT) polymerization of ferrocenylmethyl methacrylate (FcMMA), the presence of a few tryptic cleavage events can eventually result in the recruitment of a considerable amount of ferrocene redox tags. Obviously, the NAD+-eRAFT polymerization is low-cost and easy to operate as a highly efficient strategy for signal amplification. As expected, the as-constructed biosensor is highly selective and sensitive toward the signal-on interrogation of trypsin activity. Under optimal conditions, the detection limit can be as low as 18.2 μU/mL (∼72.8 pg/mL). The results also demonstrate that the as-constructed electrochemical trypsin biosensor is applicable to inhibitor screening and the interrogation of enzyme activity in the presence of complex sample matrices. Moreover, it is low-cost, less susceptible to false-positive results, and relatively easy to fabricate, thus holding great potential in diagnostic and therapeutic applications.
研究领域:
分析化学
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生物化学
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生物技术
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电化学
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酶学
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产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2025
·
IF 13.2
Xueping Tan,Dongnan Guo,Yujie Wang,Wenli Xu,Xiaofang Hou,Junbo Zhang,Sicen Wang
Factor XIa (FXIa), a pivotal target in anticoagulant therapy, requires precise activity monitoring to assess coagulation status and bleeding risks. To address the limited sensitivity of conventional chromogenic methods, we developed a novel electrochemiluminescence (ECL) biosensor exploring the synergistic effects of MXene's superior conductivity and Prussian blue analogue's (PBA) large specific surface area. Transient absorption spectrometry was employed to determine the excited-state lifetime and to elucidate the functional role of MXene@PBA. Molecular docking and specificity constant analysis identified Mpr(mercaptopropionic acid)-TEARK-Fc(ferrocene) as an optimal peptide substrate. The MXene@PBA-enhanced biosensor quantifies FXIa-induced ECL signal changes via peptide cleavage, achieving a linear range of 1.0 × 10 −5 mIU/mL to 1 mIU/mL and an LOD of 3.7 × 10 −6 mIU/mL (S/N = 3) in human serum. Furthermore, the ECL biosensor demonstrated efficacy in FXIa inhibitor screening, firstly revealing salvianolic acid A and C as potent inhibitors (>60 % inhibition) and apigenin as a moderate inhibitor (~40 %). Molecular docking confirmed that these inhibitors competitively bind to FXIa's catalytic pocket (His57, Cys58, Ala190, Lys192, Ser195), overlapping with the substrate recognition site. This MXene@PBA-enhanced ECL biosensor establishes a robust strategy for both FXIa activity monitoring and therapeutic agent development.
研究领域:
生物传感器
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纳米材料
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电化学
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分析化学
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分子生物学
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药理学
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抗凝治疗
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表面科学
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产品关联
DOI
高影响因子
JOURNAL OF NEUROCHEMISTRY
·
2018
·Vol. 148
·期 4
·550-560
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IF 4.609
Meisam Rostaminasab Dolatabad,Lu-lu Guo,Peng Xiao,Zhongliang Zhu,Qing-tao He,Du-xiao Yang,Chang-xiu Qu,Sheng-chao Guo,Xiao-lei Fu,Rui-rui Li,Lin Ge,Ke-jia Hu,Hong-da Liu,Yue-mao Shen,Xiao Yu,Jin-peng Sun,Peng-ju Zhang
s Protein Phosphatase Mg 2+ /Mn 2+ -Dependent 1K (PPM1K),also named as PP2Cm or branched-chain α-ketoacid dehydrogenase complex phosphatase, is a member of the metal-dependent phosphatase family and an important metabolic regulator. Single nucleotide polymorphisms (SNPs) in PPM1K contributing to protein functional defects have been found to be associated with numerous human diseases, such as cardiovascular disease, maple syrup urine disease, type 2 diabetes, and neurological disease. PPM1K N94K is an identified missense mutant produced by one of the SNPs in the human PPM1K coding sequence. However, the effects of the N94K mutant on its activity and structural property have not been defined. Here, we performed a detailed enzymological study using steady-state kinetics in the presence of pNPP or phospho-peptide substrates and crystallographic analyses of the wild-type and N94K PPM1K. The PPM1K-N94K significantly impaired its Mg 2+ -dependent catalytic activity and structural analysis demonstrated that the N94K mutation induced a conformational change in the key residue in coordinating the Mg 2+ in the active site. Specifically, three Mg 2+ were located in the active site of the PPM1K N94K instead of two Mg 2+ in the PPM1K wild type. Therefore, our results provide a structure basis for the metal ion-dependent PPM1K-N94K phosphatase activity.
研究领域:
生物化学
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结构生物学
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酶学
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分子生物学
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产品关联
DOI
PubMed
高影响因子
Analytical Methods
·
2019
·Vol. 11
·期 9
·1248-1253
·
IF 2.378
Dehua Deng,Yuanqiang Hao,Ping Yang,Ning Xia,Wenxue Yu,Xiuhua Liu,Lin Liu
A general peptide substrate for the specific detection of proteases is linked with a quencher/fluorophore pair. However, labeling of the substrate with a quencher/fluorophore pair may increase the complexity for the synthesis of peptides and affect the approach of protease to the cleavage site. A peptide with a specific sequence has been shown to bind Cu2+ with high affinity. More intriguingly, Cu2+ exhibits a high inherent quenching ability towards the fluorophore by complexation with the sequence-specific peptide. Based on this fact, this work reports a general single-labeled peptide substrate for the detection of protease activity, screening of potential inhibitors and evaluation of cell apoptosis. The feasibility and applications of the method were demonstrated by assays of caspase-3 and β-secretase with a signal-on and a signal-off format, respectively.
研究领域:
生物化学
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分子生物学
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分析化学
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药物发现
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）