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A novel egg-like nanosphere was designed as a long-lived catalyst and is described as FeO@ nSiO-NH-FeO• xBiO@ mSiO. The catalyst was prepared using a modified Stöber method with template-free surface-protected etching. The catalyst particle consists of a magnetic FeO core as the 'yolk', an inner silica shell bearing active FeO• xBiO species as the 'egg white', and outer mesoporous silica as the 'egg shell'. It exhibits an excellent performance in the catalytic reduction of nitro aromatics to corresponding anilines in a fixed-bed continuous-flow reactor. The reaction could be performed at 80 °C and could reach complete conversion in less than 1 min with only a 7% excess of hydrazine hydrate. The catalyst bed could be easily shifted between different substrates without cross-contamination because of the uniformity of the catalyst particles. This catalyst exhibited very good stability in the continuous-flow protocol. In the long-term reduction of p-nitrophenol with 0.5 mmol·min productivity, it worked for more than 1,500 cycles without any catalytic activity loss. [ABSTRACT FROM AUTHOR]

A rapid quantitative analytical method for three components of Lonicerae Japonicae Flos solution ( Lonicera Japonica Thumb.) extracted by water was developed using near-infrared (NIR) spectroscopy and the partial least-squares (PLS) method. The NIR spectra of 81 samples collected from a production line were obtained. The concentrations of secologanic acid, chlorogenic acid and galuteolin were determined by using high-performance liquid chromatography-diode array detection as the reference method. Several pretreatment methods for the NIR spectra were used during PLS calibration. The most appropriate latent variable number of the PLS factor was selected based on the standard error of cross-validation (SECV). The performance of the final PLS models was evaluated according to SECV, standard error of prediction (SEP) and determination coefficient (R2). The compounds secologanic acid, chlorogenic acid and galuteolin had SEP values of 0.030, 0.061 and 1.668 μg/mL, respectively and R2 values over 0.85. This work shows that NIR spectroscopy is a rapid and convenient method for the analysis of Lonicerae Japonicae Flos solution extracted by water. The proposed method can help in the application of process analytical technology in the pharmaceutical industry, particularly in traditional Chinese medicine injections. [ABSTRACT FROM AUTHOR]

Pharmacokinetic characters of rhynchophylline (RIN), gastrodin (GAS), and gastrodigenin (p-hydroxybenzyl alcohol, HBA) were investigated after oral administration of different prescriptions of Yizhi: Yizhi tablets or effective parts of tianma (total saponins from Gastrodiae, EPT) and gouteng (rhynchophylla alkaloids, EPG). At different predetermined time points after administration, the concentrations of GAS, HBA, and RIN in rat plasma were determined by an HPLC-ESI/MS method, and the main pharmacokinetic parameters were investigated. The results showed that the pharmacokinetic parameters C max and AUC0-∞ (P < 0.05) were dramatically different after oral administration of different prescriptions of Yizhi. The data indicated that the pharmacokinetic processes of GAS, HBA, and RIN in rats would interact with each other or be affected by other components in Yizhi. The rationality of the compatibility of Uncaria and Gastrodia elata as a classic "herb pair" has been verified from the pharmacokinetic viewpoint.

A method of high performance liquid chromatography-triple quadrupole mass spectrometry (HPLC-QqQ MS) in multiple reaction monitoring (MRM) mode for simultaneous determination of five Amadori compounds in tobacco has been developed. The separation was performed on an XBridge Amide column (250 mm x 4.6 mm, 3.5 microm) by gradient elution using methanol and water as mobile phases. The linearity of this method was good with the correlation coefficients (r) of 0.9895-0.9989. The limits of detection (S/N = 3) were from 3.51 microg/L to 14.86 microg/L, and the limits of quantitation (S/N = 10) were from 10.18 microg/L to 44.58 microg/L. The recoveries varied from 92.6% to 123.6% with the relative standard deviations (RSDs) less than 9.4%. The established method is rapid, accurate, robust and convenient, and it could be applied to the measurement of the five Amadori compounds in tobacco and cigarettes.

An ultra performance liquid chromatography-time of flight mass spectrometry (UP-LC/TOF MS)-based method for plasma metabolic fingerprinting analysis was established. Acquired data were analyzed by principal component analysis and orthogonal projection to latent structure-discriminant analysis. The effect of tang-shen-fang (TSF) on the treatment of diabetic nephropathy patients was evaluated. Significant changes were found after 3 and 6 months' treatment of TSF compared with placebo controls. Nineteen metabolites in plasma were identified as potential biomarkers, including lipids, fatty acids and amino acids. The present metabonomic study is helpful to grasp the changes of global metabolic networks during the treatment of TSF and to testify its clinical efficacy and understand its action mechanism.

Chemomics, the methodology for the study of traditional Chinese medicines (TCMs) on the substance basis, and chromatographic fingerprinting, the crucial technology of quality evaluation of TCMs, are introduced. The applications of chromatography as well as some related techniques in the information acquisition of TCMs are summarized. Guided by chemomics, with the results of chromatography and multi-component quantification, this research mode is of great significance to the establishment of the quality evaluation system of TCMs.