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The roots of Panax notoginseng (Burk) F. H. Chen are used as a highly valuable Chinese herbal medicine in the prevention and treatment of cardiovascular and hematological diseases. Several aerial parts of plant are usually abandoned as the wastes. Panax notoginseng inflorescence (IFO) is commonly used as a folk medicine and dietary ingredient, its fruiting stage is referred as infructescence (IFU). Owing to high chemical complexity and structural similarity of ginsenosides, the co-eluting phenomenon, especially for the isomers, is inevitable in the chromatogram, resulting in the inaccurate quantitation. A novel LCMS method using hybrid positive full scan and multiple reaction monitoring (MRM) modes was developed to characterize ginsenoside distribution in different architectural components of IFO and IFU. compound library inhibitor MRM was performed for the quantification of G-Ra2 and NG-Fp2, a pair of co-eluting isomers with identical negative MS and MS/MS characteristics, and full scan was conducted to quantify other investigated saponins. Our data indicate that flower buds have the highest abundance of the summed saponins, fruit pedicel and fruit pericarp, commonly considered as the useless by-products of seed processing, contain the abundant saponins. Additionally, the contents of the detected ginsenosides in these architectural components significantly increased along with their growth years. Our findings will facilitate comprehensive utilization and exploitation of P. notoginseng inflorescence and infructescence.Palmatine is a natural isoquinoline alkaloid widely found in traditional Chinese medicines. In this study, a simple, sensitive and rapid ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method was developed and validated for the quantification of palmatine in the plasma and tissue samples in rats. Sample preparation involved a simple protein precipitation extraction technique using acetonitrile as the precipitating solvent. Chromatographic separation was accomplished on an ACQUITY UPLC BEH C18 column with a mobile phase of acetonitrile-5 mM ammonium acetate solution (7030, v/v) at a flow rate of 0.3 mL/min. Coptisine was selected as the internal standard. The protonated analytes were determined with MRM in the positive ion mode. The assay exhibited a linear dynamic range of 1.0-1000 ng/mL for palmatine in each biological matrix and the low limit of quantification was 1.0 ng/mL. Non-compartmental pharmacokinetic parameters indicated that there is a significant difference in the apparent distribution volume and half-life between intragastric and intravenous administration modes. Palmatine could be detected in different tissues and the content in liver and kidney is relatively high, suggesting that liver and kidney might be the targeting organs of palmatine. The plasma protein binding rate test showed that the percent binding of palmatine is medium, and was found to be higher in human than in rats.A fast and reliable method based on two-channel liquid chromatography coupled to tandem mass spectrometry was developed and successfully validated for quantification of busulfan. The drug vehicle polyethylene glycol 400 was quantified simultaneously in patient samples. The sample preparation consisted of simple protein precipitation using a mixture of methanol and zinc sulphate containing busulfan-d8 as internal standard. Chromatographic separation was performed on a short biphenyl column (30 mm × 3.0 mm, 5 μm particles) using a step gradient from 30 % to 85 % methanol, ensuring co-elution of the analyte and internal standard. Quantification was performed using the mass transition of 264.1 > 151.1 for busulfan and 272.1 > 159.1 for the internal standard. Using only 20 μL of plasma sample, the lower limit of quantification was 25 ng/mL. Signal to noise ratio at the lower limit of quantification exceeded 300. The assay performance was not adversely affected by matrix effects originating from drug formulation excipients or other sample components. The coefficient of variation was ≤4 % and the mean accuracy 101-108 % across the calibration range 25-5 000 ng/mL. Chromatographic run time was 2 min and 8 s, allowing an effective run-time of 1 min and 10 s when using two alternating LC-channels. The assay has been implemented in routine practice with accreditation according to the ISO 15189 standard, and performs well in external quality control assessments. We present for the first time that shortly after an IV infusion of busulfan, the plasma levels of polyethylene glycol 400 may be in the range of 400-800 mg/L. The presence of these levels of detergent in patient samples may have detrimental effects on assay performance in LC-MS/MS, not limited to busulfan assays. This may be a concern for any LC-MS/MS analysis performed on samples collected within the first 24 h after an IV infusion of busulfan.Cystatin C (Cys C) has been proposed as a fascinating glomerular filtration rate (GFR) marker for early detection of acute kidney injury and chronic kidney disease. However, most of traditional methods for Cys C detection are immunoassays, which was tedious to perform and unfriendly for economics. In this work, a novel and simple biosensor for the sensitive measurement of Cys C via DNase I-aided recycling amplification strategy was successfully constructed based on the graphene oxide (GO) and fluorophore-labelled aptamer, which can be used to the early prediction of kidney injury. The fluorescence of fluorophore-labelled aptamer was quenched by GO based on the Fluorescence Resonance Energy Transfer (FRET) and recovered with the existence of Cys C. In addition, the DNase I enzyme would digest the fluorophore-labelled aptamer and dissociate the Cys C to launch the next reaction, resulting in an increase of signal amplification. Hence, the limit of detection is found to be 0.16 ng mL-1, which is almost 3 times lower than that without DNase I. Consequently, the developed biosensor offers a novel approach towards simple and rapid detection of Cys C based on the integration of GO and aptamer. Conceivably, this strategy holds a wide scope in the application of numerous other analytes if corresponding aptamers are available.

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