Forensic Toxicology
·
2016
·Vol. 34
·期 2
·398-402
·
IF 0
Shintani-Ishida Kaori,Kakiuchi Yasuhiro,Ikegaya Hiroshi
The toxicological detection of the new synthetic cathinone 4′-methyl-α-pyrrolidinohexanophenone (MPHP) in urine samples has been impossible, because much of MPHP is metabolized before its excretion into urine. In this study, we successfully quantified unmetabolized MPHP in urine of an autopsy case using a sensitive method by liquid chromatography–time-of-flight-mass spectrometry. The quantification method showed good linearity in the range of 1.00–100 ng/mL, and the limit of detection was 0.5 ng/mL in human urine. In the autopsy case, the concentrations of MPHP in urine, plasma, and liver tissue samples were determined to be 60.1, 32.9 ng/mL, and 63.1 ng/g, respectively.
研究领域:
法医学
·
分析化学
·
毒理学
✓ 已验证
DOI
PubMed
APPLIED BIOCHEMISTRY AND BIOTECHNOLOGY
·
2016
·Vol. 182
·期 2
·482-494
·
IF 1.606
Bai Yin,Zhou Wen-Di,Mu Xian-Min,Zhang Qian,Yu Chen,Di Bin,Su Meng-Xiang
Human 17β-hydroxysteroid dehydrogenase type 1 (17β-HSD1), a potential target in breast cancer prevention and therapy, was extracted from human placenta and immobilized on nonporous silica (∼5 μm) with a covalent method for the first time. The optimum initial enzyme concentration and immobilization time during the immobilization process were 0.42 mg mL −1 and 12 h, repectively. The binding was confirmed by scanning electron microscope (SEM) and infrared spectroscopy (FT-IR). It could improve the pH, thermal and storage stability compared to free enzyme. Moreover, the immobilized enzyme could be reused at least four times. A screening method based on it coupled with liquid chromatography–time-of-flight mass spectrometer (LC-TOF/MS) was established, and the half-maximal inhibitory concentration (IC 50) of apigenin for the immobilized enzyme was 291 nM. Subsequently, 10 natural products were evaluated leading to inhibition of the activity of 17β-HSD1 at the concentration of 25 μM, and six of them inhibit the activity over 50%.
研究领域:
生物化学
·
药物开发
·
肿瘤学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF PHARMACEUTICAL AND BIOMEDICAL ANALYSIS
·
2016
·
IF 3.169
Yidi Yang,Xi Zhu,Fei Zhang,Wei Li,Ying Wu,Li Ding
Stress testing was carried out under acidic, alkaline, oxidative, thermal and photolytic conditions to evaluate the intrinsic stability of posaconazole injection. A total of four degradation products were detected and the drug was found to be susceptible to oxidative and thermal degradations. Three unknown degradants formed under oxidative stress condition were isolated by preparative HPLC and unambiguously elucidated by LC–TOF/MS, LC–MS/MS, 1 H NMR, 13 C NMR and 2D NMR techniques. Based on the spectrometric and spectroscopic information, these novel degradation products were unequivocally assigned as the N-oxides of posaconazole. Probable mechanisms for the formation of the degradants were proposed. A new and selective HPLC method was developed and validated to separate, detect and quantify all the degradants in posaconazole injection.
研究领域:
药物分析
·
药学
·
质谱分析
·
核磁共振
✓ 已验证
产品关联
DOI
PubMed
高影响因子
MOLECULES
·
2024
·Vol. 29
·期 20
·4862
·
IF 4.2
Li Song,Yan Liang,Yilin Li,Tingting Guo,Hui Li,Shuxuan Liang
With the advantages of a high specificity, a long half-life, and a high safety, the use of antibody biologic drugs, including camrelizumab, has been rapidly increasing in clinical practice. Camrelizumab, an immune checkpoint inhibitor and humanized monoclonal antibody, is used to treat several advanced solid cancers. Measuring its concentration supports personalized dosage adjustments, influences treatment decisions for patients, strengthens the control of disease activity through therapeutic drug monitoring, and helps evaluate and prevent drug interactions in combination therapy. Because antibodies are present in complex biological matrices, quantifying monoclonal antibody drugs is challenging, and must rely on precise, selective, and reliable analytical methods. In this study, a quadrupole time-of-flight mass spectrometry TripleTOF 6600+ (AB SCIEX, Framingham, MA, USA) system equipped with a Turbo V ion source was used for the qualitative analysis of monoclonal antibodies using the data-dependent acquisition (IDA) MS/MS mode, followed by quantitative analysis using a targeted MRMHR workflow. This method showed a good linear relationship within the range of 4–160 μg/mL, with a correlation coefficient of R2≥ 0.996. It demonstrated an acceptable accuracy (88.95–101.18%) and precision (≤15%). Furthermore, the lower limit of quantification was found to be 4 μg/mL, with the lowest detection limit of 0.3217 μg/mL, indicating that this method is rapid, accurate, and reliable for the quantitative analysis of camrelizumab in human serum.
研究领域:
药理学
·
分析化学
·
临床医学
·
质谱学
·
药物开发
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）