建立了通过式固相萃取净化-超高效液相色谱-串联质谱法测定婴幼儿配方奶粉中的10种季铵盐类消毒剂(QACs)残留的方法。样品经水溶解后,用含0.2%甲酸的乙腈提取,提取液用甲醇1∶1混匀,用通过式固相小柱(Oasis PRiME HLB)净化,流动相由含0...建立了通过式固相萃取净化-超高效液相色谱-串联质谱法测定婴幼儿配方奶粉中的10种季铵盐类消毒剂(QACs)残留的方法。样品经水溶解后,用含0.2%甲酸的乙腈提取,提取液用甲醇1∶1混匀,用通过式固相小柱(Oasis PRiME HLB)净化,流动相由含0.2%甲酸的甲醇-乙腈溶液(体积比,6∶4)与含0.2%的甲酸水溶液组成。10种QACs在Waters CORTECS UPLC C18(100 mm×2.1 mm,1.6μm)色谱柱上以梯度洗脱分离后,采用电喷雾离子源正离子(ESI+)模式电离,配合多反应监测模式(MRM)进行定性定量分析。结果表明,10种QACs在各自浓度范围内线性良好,相关系数r^(2)≥0.9964,方法定量限(LQD)为0.5~3.0μg/kg。采用低、中、高3个浓度水平进行加标实验,回收率范围为86.2%~103.4%。方法简单高效,可作为日常婴幼儿配方奶粉监督抽样中10种季铵盐类消毒剂(QACs)残留检测的有效方法。展开更多
目的:建立毛细管区带电泳(CZE)分离/安培检测左旋多巴(DP)、多巴胺(DA)、肾上腺素(EP)、去甲肾上腺素(NE)、5-羟色胺(5-HT)5种儿茶酚胺类神经递质(CAs)药物的方法。方法:采用石英毛细管柱(60 cm×50μm),含8 mmol·L^(-1)对-(...目的:建立毛细管区带电泳(CZE)分离/安培检测左旋多巴(DP)、多巴胺(DA)、肾上腺素(EP)、去甲肾上腺素(NE)、5-羟色胺(5-HT)5种儿茶酚胺类神经递质(CAs)药物的方法。方法:采用石英毛细管柱(60 cm×50μm),含8 mmol·L^(-1)对-(季铵盐)杯[4]芳烃(QAC4A)的125 mmol·L^(-1)磷酸氢二钠溶液(Na_2HPO_4,pH 7.0)为缓冲液,分离电压6 kV,分离 CAs 并利用 Cu 微粒修饰碳纤维电极检测。结果:优化条件下5种 CAs 被基线分离,回收率为92%～105%,5种 CAs 在0.2～1000μmol·L^(-1)浓度内呈良好线性关系,最低检测限为0.2 μmol·L^(-1)。应用该方法成功地测定了5种 CAs 注射液、正常人和嗜铬细胞瘤患者尿样。结论:本法用于分离并检测 CAs 药物,具有准确、灵敏、简便的特点,适合该类药品分析。展开更多
Intensification of pollution loading worldwide has promoted an escalation of different types of disease-causing microorganisms, such as harmful algal blooms(HABs), instigating detrimental impacts on the quality of rec...Intensification of pollution loading worldwide has promoted an escalation of different types of disease-causing microorganisms, such as harmful algal blooms(HABs), instigating detrimental impacts on the quality of receiving surface waters. Formation of unwanted disinfection by-products(DBPs) resulting from conventional disinfection technologies reveals the need for the development of new sustainable alternatives. Quaternary Ammonium Compounds(QACs) are cationic surfactants widely known for their effective biocidal properties at the ppm level. In this study, a novel silica-based antimicrobial nanofilm was developed using a composite of silica-modified QAC(Fixed-Quat) and applied to a fiberglass mesh as an active surface via sol–gel technique. The synthesized Fixed-Quat nanocoating was found to be effective against E. coli with an inactivation rate of 1.3 × 10^(-3) log reduction/cm min. The Fixed-Quat coated fiberglass mesh also demonstrated successful control of Microcystis aeruginosa with more than 99% inactivation after 10 hr of exposure.The developed antimicrobial mesh was also evaluated with wild-type microalgal species collected in a water body experiencing HABs, obtaining a 97% removal efficiency. Overall,the silica-functionalized Fixed-Quat nanocoating showed promising antimicrobial properties for water disinfection and HABs control, while decreasing concerns related to DBPs formation and the possible release of toxic nanomaterials into the environment.展开更多
文摘目的:建立毛细管区带电泳(CZE)分离/安培检测左旋多巴(DP)、多巴胺(DA)、肾上腺素(EP)、去甲肾上腺素(NE)、5-羟色胺(5-HT)5种儿茶酚胺类神经递质(CAs)药物的方法。方法:采用石英毛细管柱(60 cm×50μm),含8 mmol·L^(-1)对-(季铵盐)杯[4]芳烃(QAC4A)的125 mmol·L^(-1)磷酸氢二钠溶液(Na_2HPO_4,pH 7.0)为缓冲液,分离电压6 kV,分离 CAs 并利用 Cu 微粒修饰碳纤维电极检测。结果:优化条件下5种 CAs 被基线分离,回收率为92%～105%,5种 CAs 在0.2～1000μmol·L^(-1)浓度内呈良好线性关系,最低检测限为0.2 μmol·L^(-1)。应用该方法成功地测定了5种 CAs 注射液、正常人和嗜铬细胞瘤患者尿样。结论:本法用于分离并检测 CAs 药物,具有准确、灵敏、简便的特点,适合该类药品分析。
基金supported by Citrus Disease Research and Extension(CDRE)(grant no.2016-70016-24828/project accusation no.1008984)from the USDA National Institute of Food and Agriculture
文摘Intensification of pollution loading worldwide has promoted an escalation of different types of disease-causing microorganisms, such as harmful algal blooms(HABs), instigating detrimental impacts on the quality of receiving surface waters. Formation of unwanted disinfection by-products(DBPs) resulting from conventional disinfection technologies reveals the need for the development of new sustainable alternatives. Quaternary Ammonium Compounds(QACs) are cationic surfactants widely known for their effective biocidal properties at the ppm level. In this study, a novel silica-based antimicrobial nanofilm was developed using a composite of silica-modified QAC(Fixed-Quat) and applied to a fiberglass mesh as an active surface via sol–gel technique. The synthesized Fixed-Quat nanocoating was found to be effective against E. coli with an inactivation rate of 1.3 × 10^(-3) log reduction/cm min. The Fixed-Quat coated fiberglass mesh also demonstrated successful control of Microcystis aeruginosa with more than 99% inactivation after 10 hr of exposure.The developed antimicrobial mesh was also evaluated with wild-type microalgal species collected in a water body experiencing HABs, obtaining a 97% removal efficiency. Overall,the silica-functionalized Fixed-Quat nanocoating showed promising antimicrobial properties for water disinfection and HABs control, while decreasing concerns related to DBPs formation and the possible release of toxic nanomaterials into the environment.
