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Fangji Huangqi Decoction (FHD) is a classic prescription of traditional Chinese medicine which is recorded in "Jin Gui Yao Lue". The purpose of this study is to develop a method for simultaneous determination multicomponent in FHD. The separation of the 19 compounds that included calycosin, calycosin-7-O-β-D-glucoside, formononetin, ononin, methylnissolin, methylnissolin-3-O-glucoside, isomucronulatol, tetrandrine, fangchinoline, atractylenolide-I, atractylenolide-III, liquiritigenin, liquiritin, isomucronulatol-7-O-β-D-glucoside, astragaloside-I, astragaloside-II, astragaloside-III, astragaloside-IV and glycyrrhetinic acid were achieved by linear gradient elution. The 19 components were identified by comparing the chromatographic peaks with the reference compounds and were quantitatively analyzed by multiple reaction monitoring. This method was strict validated with recovery (96.10–101.70%), precision [relative standard deviation (RSD), 1.34–3.34%], stability (RSD, 1.49–3.80%) and repeatability (RSD, 1.60–3.49%), respectively. All the compounds showed good linearities (R 2 > 0.999). The limit of detection (LOD) and limit of quantitation (LOQ) for the 19 compounds were in the range of 0.03–0.27 μg/mL (LODs) and 0.05–1.23 μg/mL (LOQs). The correlation analysis indicated that astragalus flavonoids were negatively correlated with astragalosides, tetrandrine and their corresponding flavonoid glycosides, and atractylenolides were positively correlated with astragalosides and fangchinoline. This method proved to be reliable and effective, which would give a helpful basis for the quality control, pharmacological and pharmacokinetic of FHD. [ABSTRACT FROM AUTHOR]

Danggui Buxue decoction (DBD), a classic prescription of traditional Chinese medicine (TCM) for invigorating qi and generating blood, contains honey‐processed Astragali Radix (HAR) and wine‐processed Angelicae Sinensis Radix (WDG) in its original prescription. In this study, the compositions of DBD, WDG, and HAR were characterized using ultra‐high‐performance liquid chromatography coupled with the quadrupole‐time‐of‐flight tandem mass spectrometry technique in combination with molecular network and diagnostic ion strategies. Finally, 200 compounds were identified in DBD, 114 compounds were identified in WDG, and 180 compounds were identified in HAR; there were 48 common compounds in total. The results demonstrated that compatibility led to changes in the chemical composition of TCM, and the qualitative method used in this study provided an effective data processing strategy for the characterization of components and the database for the study of the compounding mechanism of TCM. [ABSTRACT FROM AUTHOR]

A novel amphiphilic silicon-polyurethane antifouling polymer was synthesized with PDMS as the main chain and hydrophilic polymer as the side chain. With N-vinylpyrrolidone and butyl acrylate as raw materials, hydrophilic side chains were synthesized by free radical copolymerization and introduced into the silicone polyurethane system as chain extenders. Due to the hydrogen bond interaction between carbamate bonds, the prepared silicone-polyurethane polymer has high mechanical properties (tensile strength > 14 MPa, elongation at break > 1 200%) and high substrate adhesion (> 1 MPa). After introducing hydrophilic side chain, the polymer still has a low surface energy (24. 1 mJ/m²), and the antibacterial adhesion rate to Pseudomonas was 98%. In addition, MS software was used to simulate the number of hydrogen bonds and free volume molecular structure, which explained that the introduction of hydrophilic side chains led to the decline of mechanical properties because the macromolecular side chains weakened the interaction between polymer segments. [ABSTRACT FROM AUTHOR]

Huangqi Jianzhong Tang (HQJZ), a famous traditional Chinese medicine formula, is widely used in the treatment of gastrointestinal diseases in China. In this study, an ultra-high-performance liquid chromatography coupled with quadrupole-Exactive mass spectrometry was used to identify the metabolites in rat urine and feces after oral administration of HQJZ coupled with Compound Discover 3.0 software. The possible metabolic pathways were calculated and deduced based on 71 previous detected prototype compounds. As results, 88 compounds were identified in urine and feces, respectively. In urine sample, we identified 20 prototype compounds and 68 related metabolites. Meanwhile, a total of 21 prototype compounds and 67 related metabolites were identified in feces. Among them, flavonoids and saponins were the main ingredients in vivo. Further, we also speculated that HQJZ experienced oxidation, reduction, acetylation, methylation and glucuronic acid reaction in urine and feces. This study established a reliable method for the detection of prototype components and metabolites of traditional Chinese medicines, which would provide helpful information for further research into the active substances of HQJZ. [ABSTRACT FROM AUTHOR]

Silicone elastomers are widely used in aviation, electronics, automotive, and medical device fields, and their overuse inevitably causes recycled problems. In addition, the elastomers are subject to attack by bacteria and fire during use in some application scenarios, which is a safety hazard. Therefore, there is a great need to prepare silicone elastomers with improved antibacterial, flame retardant, self‐healing, and recyclable functions. A new strategy is proposed to prepare silicone elastomers with bio‐based tannic acid as cross‐linkers to solve this problem by using polydimethylsiloxane as a soft chain segment and 2,2‐bis(hydroxymethyl)propionic acid as an intermediate chain extender. Based on the phenol carbamate bonding and hydrogen bonding interactions, the elastomer has efficient self‐healing ability and can achieve dynamic dissociation at 120 °C for complete recovery. In addition, due to the unique spatial structure and polyphenolic hydroxyl groups of tannic acid, the mechanical properties of the elastomer are greatly improved with an antimicrobial efficiency of over 90% and a final oxygen index of 25.5%. The multifunctional silicone elastomer has great potential applications in recyclable refractory materials and antimicrobial materials. [ABSTRACT FROM AUTHOR]

Heat curable blended methylfluorosilicone rubber (MFSR) was prepared by combination of methylsilicone rubber (MSR) and fluorosilicone rubber (FSR). 2,5-Bis(-tert-butylperoxy)-2,5-dimethylhexane (DBPMH) was chosen as a curing agent. Poly(methylsiloxane-co-fluo-rosiloxane) with low molecular weight was used as an interfacial agent. Curing characteristics, mechanical properties, low temperature performance, and hot oil resistance of blended MFSR was studied in details. The results showed that MSR and FSR could reach co-vulcanization by DBPMH in blended MFSR. Higher FSR content could improve the scorch safety, lower the rate of curing reaction, and lead to the poor processability of blended MFSR. An increase of FSR content also improved the hot oil resistance of blended MFSR. Interfacial agent could limit the phase separation of MSR and FSR, make the blended system more thermodynamically stable and elevate the mechanical properties of blended MFSR. Differential scanning calorimetry (DSC) measurements revealed that increasing MSR content lowered the glass transition temperature ([T.sub.g]) and improved the low-temperature flexibility of blended MFSR when MSR was no more than 15%. POLYM. ENG. SCI., 53:52-58, 2013. © 2012 Society of Plastics Engineers, INTRODUCTION Silicone rubbers, based on high molecular weight poly-diorganosiloxane, have been widely used because of their unique characteristics endued by Si-0 chains (1-3). For example, methylsilicone rubber (MSR) exhibits superior [...]