HPTLC-bioautography/SERS screening nifedipine adulteration in food supplement based on Ginkgo biloba

Publication date: Available online 15 January 2020Source: Microchemical JournalAuthor(s): Yisheng Chen, Caihong Huang, Zhengyu Jin, Xueming Xu, Yina Cai, Yuxiang BaiAbstractGinkgo biloba was a popular phytomedicine as the essential ingredient of many food supplement. In this work, a bio-inspired HPTLC method was proposed for the visualized screening of nifedipine adulteration in food supplement based on Gingko biloba. To customize the visualization of the analyte by inhibiting bacterium (Photobacterium phosphoreum) bioluminescence, the silica gel plate that gives the highest detectability was selected as the stationary phase of separation. Thereafter, the HPTLC procedure (toluene and ethyl acetate 8/2, v/v, as the mobile phase, to a distance of 60 mm) was optimized and standardized as a sample cleanup tool to exclude noises caused by bioactive co-extracts. Then, the separation result fixed on the plate layer was selectively visualized as dark bands against the white background, only after 6 min exposure. To achieve quantitation of the obtained HPTLC images, an enhanced quantitative analysis was optimized via software (ImageJ) facilitated pixel scanning, offered remarkable sensitivity (LOD=24.0 μg/g), linearity (R2=0.9985 within 50-300 ng/band) and precision (RSD<7.2%). Further, the developed method was validated with real samples (recovery rates within 81.0-92.8%). In conjunction with image quantitation, in-situ surface enhance Raman spectroscopy was incorporated into th...
Source: Microchemical Journal - Category: Chemistry Source Type: research