ABSTRACT
The dosage of asarum in Qing-Fei-Pai-Du decoction (QFPD) is twice the dosage prescribed by the Chinese Pharmacopoeia. Due to the potential toxicity of aristolochic acid I (AAI), a limited component in asarum, the possibility that its dosage also exceeds the dosage prescribed by the Chinese Pharmacopoeia had aroused wide concern. In this study, the UHPLC-Q TOF method was used to determine the presence of AAI in QFPD. A UHPLC-QQQ method was then established to determine the content of AAI in QFPD, a reflux extract of asarum and an ultrasonic extract of 70% methanol of asarum. The results showed that the amount of AAI in the three samples was approximate 1.5, 3.2 and 9.0 μg respectively with equivalent dosages of asarum (6 g). All were obviously lower than the maximum daily limit stipulated in the Chinese Pharmacopoeia (30 μg). Therefore, we concluded that the content of AAI could be effectively reduced by using a Chinese herbal compound decoction and optimization of asarum. This assay is not only convenient, rapid, sensitive and reproducible for the trace detection of AAI in Chinese herbal compound decoction, but also useful for the rational application of asarum in QFPD.
ABSTRACT
Objective To develop a method combining surface-enhanced Raman scattering (SERS) spectrum and electrostatic adsorption for detecting circulating tumor cells. Methods Graphene oxide was non-covalently functionalized by poly(sodium-p-styrenesulfonate) (PSS), and graphene oxide/gold nanorod (GO/GNR) hybrids were in situ synthesized via gold seeding growth approach. Then, GO/GNR hybrids were non-covalently functionalized by poly dimethyl diallyl ammonium chloride (PDDAC) to make the surface of GO/GNR positively charged. GO/GNR hybrids would target the tumor cells by electrostatic interaction. SERS technology was used to detect the composites of GO/GNR-tumor cells. The blood samples of healthy volunteers were collected, and the tumor cells of different densities were added to the blood samples to make simulated blood samples. The tumor cells in simulated blood samples were detected using the above methods. Results Positively charged GO/GNR hybrids could efficiently target the tumor cells. SERS spectroscopy could detect tumor cells within 50 to 10 000 cells. However, white blood cells might interfere the detection of tumor cells. Conclusion GO/GNR hybrids may serve as SERS probes for detection of circulating tumor cells via Raman spectroscopy.
ABSTRACT
AIM:To determine the content of the trace arsenic and mercury in Fructus Mume and Fructus Mume charcoal. METHODS:Atomic fluorescence spectrometry was used. RESULTS:The content of arsenic in Fructus Mume is 0.0597～1.0001 mg?g -1, that of mercury is 0.0198～0.0300 mg?g -1. CONCLUSION:This method is simple to handle, the quantitative analysis is accurate.