JOURNAL OF PHARMACEUTICAL AND BIOMEDICAL ANALYSIS
·
2021
·
IF 3.935
Chunyi Liu,Jie Tang,Yingjiao Xu,Shanshan Cao,Yi Fang,Chao Zhao,Zhengping Chen
[ 18 F]fluoropropyl-(+)-dihydrotetrabenazine ([ 18 F]FP-(+)-DTBZ) is a rising positron tracer for imaging vesicular monoamine transporter II (VMAT2) in the central nervous system. The present work was to develop a novel chromatographic method capable of the molar activity (A m ) determination of [ 18 F]FP-(+)-DTBZ. As a complement work of the A m measurement, we also investigated the effect of A m on the quantitative analysis of VMAT2 autoradiography with [ 18 F]FP-(+)-DTBZ. The A m determination was performed by high performance liquid chromatography (HPLC) using the non-radioactive standard (FP-(+)-DTBZ) for calibration plot of peak area against concentration. Based on this correlation, the A m of [ 18 F]FP-(+)-DTBZ was calculated and corrected to the end of synthesis. In the quantitative analysis of in vitro VMAT2 autoradiography, the striatum radioactivity uptake together with the uptake ratio of striatum versus cortex reduced along with the decrease of A m and the increase of the FP-(+)-DTBZ content. Therefore, the A m and the corresponding FP-(+)-DTBZ content have a significant effect on the quantitative analysis of VMAT2 autoradiography using [ 18 F]FP-(+)-DTBZ.
研究领域:
神经生物学
·
药学
·
放射医学
✓ 已验证
DOI
PubMed
高影响因子
NATURAL PRODUCT RESEARCH
·
2014
·
IF 1.225
Ji-Bei Liang,Zhong-Duo Yang,Zong-Mei Shu,Cheng-Cheng Yu
It is well known that the isolation of monoamine oxidase (MAO) inhibitors from natural sources is an important strategy for drug development in the treatment of depression, Parkinson's disease and Alzheimer's disease. The present work describes developing a thin-layer chromatography (TLC) bioautographic method for detecting MAO inhibitors from plant extracts. The basic principle of the method is that the enzyme oxidises tryptamine into an aldehyde which in turn reacts with 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyltetrazolium bromide to form a blue formazan which makes a blue-coloured background on the TLC plates. Inhibitors of MAO produced white spots on the background. The new TLC bioautographic method has several advantages such as lower consumption of the enzyme, shorter experimental time, more easily observed background of TLC plate and better reproducibility. The detection limits were 10 ng for several known MAO inhibitors.
研究领域:
药理学
·
植物化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Food Science and Human Wellness
·
2024
·
IF 5.6
Yisheng Chen,Xingjun Xi
As a widely used food preservative, methyl paraben was experimentally evidenced with serious hormone-like adverse effects. Herein, a high performance thin-layer chromatography platformed bioluminescent bioautography and image analysis for the selective quantification and confirmation of methyl paraben was proposed and validated in vinegar and coconut juice. First, the detectability of the bioautography to the analyte on different layer materials was estimated, revealing that normal silica gel was the best choice. After that, the liquid of sample extract and working solution were separated to overcome the background noises due to co-extracted matrices. The separation result was then coupled to the optimized bioautography, enabling instant and straightforward screening of the targeted compound. For accurate quantification, bioluminescent inhibition pattern caused by the analyte was processed by image analysis, giving useful sensitivity (LOD > 16 mg/kg), precision (RSD < 10.1 %) and accuracy (spike-recovery rate 76.9 %–112.2 %). Finally, the suspected result was confirmed by determining its MS fingerprint, further strengthening the reliability of screening.
研究领域:
食品科学
·
分析化学
·
毒理学
✓ 已验证
产品关联
DOI
高影响因子
PHYTOCHEMICAL ANALYSIS
·
2011
·Vol. 22
·期 6
·509-515
·
IF 1.848
Zhong-Duo Yang,Zhu-Wen Song,Jin Ren,Ming-Jun Yang,Shuo Li
Introduction Thin-layer chromatography (TLC) bioautographic method is a simple and rapid method to screen acetylcholinesterase inhibitors from plant extracts. However, the high consumption of enzyme (6 U/mL) in current methods makes the procedure expensive, which is an obstacle to scientific research centers lacking funding. Objective To develop a new low-cost TLC bioautographic method. Methodology A series of compounds, as substrates, were synthesised and their ability to be hydrolysed by acetylcholinesterase was evaluated by the HPLC method. Results 4-Methoxyphenyl acetate ( 14 ) was proved to be an appropriate substrate for TLC bioautographic assay. Therefore a new and cheap TLC bioautographic assay was set up. The mechanism of this new method is that the enzyme converts 4-methoxylphenyl acetate into 4-methoxyphenol, which reacts with a solution of potassium ferricyanide ([K 3 (FeCN) 6 ]) and iron chloride hexahydrate (FeCl 3 . 6H 2 O) to make an aquamarine blue coloured background on the TLC plates. Regions of the TLC plate which contain acetylcholinesterase inhibitors show up as light yellow spots against the background. The consumption of enzyme (1 U/mL) in the new method is low and the detection limit of two known acetylcholinesterase inhibitors, huperzine A (0.0001 μg) and physostigmine (0.001 μg), for this assay are close to published values. Conclusion A low-cost TLC bioautographic method was developed, which will benefit research groups pursuing natural acetylcholinesterase inhibitors. Copyright © 2011 John Wiley & Sons, Ltd.
研究领域:
药理学
·
植物化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
PHYTOCHEMICAL ANALYSIS
·
2025
·
IF 2.6
Zhijun Wang,Xiaomeng Tang,Lei Lv,Sicong Qiao,Mengxin Chen,Hongjie Song
Introduction Antimicrobial resistance and free radical-mediated oxidative stress and inflammation involved in many pathological processes have become treatment challenges. One strategy is to search for antimicrobial and antioxidant ingredients from natural aromatic plants. This study established a rapid and high-throughput effect-component analysis method to screen active ingredients from Ligusticum chuanxiong essential oil (CXEO). Objective The study aims to screen phthalides with antimicrobial and antioxidant activities from CXEO by high-performance thin-layer chromatography (HPTLC)-bioautography combined with HPLC-TOF/MS method. Methods Antimicrobial activity was evaluated by disc diffusion and micro broth dilution methods. Antioxidant capacity was performed by DPPH scavenging test. Phthalides in CXEO were identified using HPLC-TOF/MS method. HPTLC–bioautography technique was established to screen phthalides of antifungal and antioxidant activities. Results CXEO had significant inhibitory activity against Candida albicans , weak or undetected inhibitory activity against Staphylococcus aureus , Escherichia coli , and Pseudomonas aeruginosa . For tested strains of C. albicans , inhibition zone diameters ranged from 13 to 17 mm, and MICs were from 0.5 to 2 mg mL −1 . CXEO also had strong antioxidant activity, IC 50 value for scavenging DPPH free radicals was 1.014 ± 0.014 mg mL −1 . Nine phthalides in CXEO were tentatively identified. Ligustilide and senkyunolide A were screened to have both antimicrobial activity against C. albicans and strong DPPH scavenging property. Conclusion HPTLC-bioautography–MS-guided strategy is very practical for high-throughput screening of antifungal and antioxidant phthalides from CXEO. In vitro experiments have shown that phthalides and CXEO have good biological activities, which may be used to the treatment of C. albicans infection or oxidative stress damage caused by various diseases. The therapeutic potential should be validated in vivo in the future.
研究领域:
药理学
·
植物化学
·
微生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Science of Advanced Materials
·
2019
·Vol. 11
·期 6
·893-901
·
IF 1.158
Zhang Zhongtao,Zhang Guangkun,Ji Jingtian,Gao Zhonghui
Nuclear magnetic resonance imaging (MRI) has high image resolution and is widely used in the medical field, but it has the problem of inadequate sensitivity. Therefore, contrast material is needed to enhance the image clarity and accuracy of MRI. In order to further improve the cell
resolution of magnetic resonance imaging (MRI), a new contrast agent, BaYbF5/BaGdF5-Tm, Yb, is obtained by using BaYbF5 and BaGdF5 as the main raw materials and using high temperature thermal decomposition method. A layer of polyethylene glycol (PEG) is added to the material
from the point of view of biocompatibility. TEM and XRD are used to characterize the material, and MTT is used to test the cytotoxicity of the material. The material is used in the imaging process of stem cell-Danhong in the treatment of cerebral infarction. Bioluminescence imaging, immunofluorescence
testing and autoradiography are carried out. A large number of tests have confirmed that the material has low cytotoxicity and is similar to the existing contrast agents in MRI imaging. In bioluminescent imaging experiments, using BaYbF5/BaGdF5-Tm, Yb contrast agent can enhance the optical
density of imaging. In autoradiography test, using BaYbF5/BaGdF5-Tm, Yb contrast agent can clearly show the changes of various tissues. In immunofluorescence test, using BaYbF5/BaGdF5-Tm, Yb contrast agent can find more vascular proliferation cells survive. The new contrast agent proposed
in this study can enhance the imaging ability of MRI. Compared with conventional contrast agents, it has higher cell resolution and lower cytotoxicity. It has positive significance for future disease detection in medicine.
研究领域:
医学影像学
·
神经病学
·
材料科学
·
生物医学工程
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）