Carboxylated graphene oxide/polyvinyl chloride as solid-phase extraction sorbent combined with ion chromatography for the determination of sulfonamides in cosmetics

A carboxylated graphene oxide/polyvinyl chloride (CGO/PVC) material was prepared as a sorbent for the selective extraction of sulphonamides from complex sample. After being dispersed in buffer solution, sample was transferred into the prefabricated solid-phase extraction (SPE) column, which integrated extraction and cleanup into one single-step. A multi-response optimization based on the Box-Behnken design was used to optimize factors affecting extraction efficiency. Compared with the commonly commercial sorbents including MCX, WCX and C₁₈, CGO/PVC hybrid material had higher extraction selectivity and capacity to sulphonamides. The limits of detection and quantification for seven target compounds were in the range of 3.4–7.1 μg/L and 11.4–23.7 μg/L, respectively. The self-assembly SPE cartridge was successfully used to enrich seven analytes in anti-acne cosmetics prior to ion chromatography detection with good recoveries of 87.8–102.0% and relative standard deviations of 1.2–6.4%, implying that this method was suitable for routine analysis of cosmetics.     

静态化学发光法测定祛痘化妆品中过氧化苯甲酰

建立了静态注射化学发光分析法测定化妆品中氧化苯甲酰(BPO)的方法,利用碱性介质中Co2+对BPO与鲁米诺(Luminol)的发光反应有催化作用,研究了影响化学发光的各种因素,探讨了可能的机理.结果表明,1.25×10-7g/LLuminol在2.5×10-4g/L Na2CO3-Na1HCO3缓冲溶液中以5×10-7...     

Green approach to synthesize nano zinc oxide via Moringa oleifera leaves for enhanced anti-oxidant,anti-acne and anti-bacterial properties for health & wellness applications

This article explores green synthesis as a strategic and sustainable route to fabricate potent zinc oxide nanoparticles. Natural green based antibacterial agents and alternatives are being introduced in the market however there is a dearth in green approach moringa based zinc oxide nanoparticles in personal care products and establishing efficacy. Moringa oleifera comprises various phytochemicals that act as non-toxic stabilizing and reducing agents. Green synthesized ZnO nanoparticles (GsZnO-Nps) were investigated for their morphological and physicochemical properties using various advanced characterizing techniques. The hexagonal wurtzite structure of GsZnO-Nps is determined by X-ray diffractometry (XRD), the average crystallite size is 13.82 nm, total crystallinity was 95.91 % and high specific-surface-area is 77.38 m²/g. Scanning Electron Microscope (SEM) revealed the formation of spherical nanoparticles having a diameter of 50 nm. UV–vis spectrum shows high bandgap energy of 3.36 eV. Results have shown that antioxidant efficacy of GsZnO-Nps is significantly higher than AR-Grade ZnO, evaluated by using 2, 2-diphenyl-1-picrylhydrazyl (DPPH) assay. Half-maximal inhibitory concentration (IC₅₀) of GsZnO-Nps was 21.72 µg/mL and AR-Grade ZnO was 345.57 µg/mL. GsZnO-Nps (0.0183 g/mL) shows robust anti-acne efficacy against Cutibacterium acne (C. acne) organism which estimated by ZOI technique, have average ZOI of 33 mm, with standard error 0.577 mm. Antibacterial efficacy of GsZnO-Nps was established at different concentrations (10, 50, 100, and 200 µg/mL) against Gram-positive and Gram-negative pathogens by zone-of-inhibition (ZOI) method with respect to standard drugs. GsZnO-Nps at 200 µg/mL exhibits high ZOI of 26.75 mm against Escherichia coli (E. coli) and ZOI of 30 mm against Staphylococcus aureus (S. aureus) organisms respectively which is comparatively higher or equal to standard drugs. The minimum inhibitory concentration (MIC) of GsZnO-Nps is 500 µg/mL to inhibit the microbe's growth. GsZnO-Nps established the added benefits of moringa phytochemicals and is an excellent approach to developing eco-friendly and multi-functional versatile products having strong antioxidants, anti-acne and advanced antibacterial efficacy for numerous industrial applications like cosmetic, health hygiene products, drugs, therapeutic etc.