试纸法快速测定保健品中茶多酚含量的研究

提出了一种方便、快速、半定量、可视化的茶多酚试纸检测新方法。实验表明,在pH 7⁸时,茶多酚与试纸上的酒石酸亚铁生成蓝紫色的三元络合物并且颜色深度和茶多酚含量成正比,之后通过与标准色阶对比即可得出茶多酚的含量。试纸可以在5 min之内实现对茶多酚含量的快速检测,最低检测限为0.005 g/L。通过和HPLC检测结果的对比,证明本试纸可以用于实时检测保健品中的茶多酚含量,检测结果具有较高的准确性和灵敏性。     

试纸法快速检测果蔬中敌敌畏含量的研究

基于比色法原理,以定量滤纸为纸基,以间苯二酚溶液为显色剂,研制出一种快速检测果蔬中有机磷农药敌敌畏的试纸。结果表明,此方法的检出限为12.5 mg/kg,检测时间仅需5 min。该试纸法具有成本低、耗时短、操作简单、携带方便等优点,适合于果蔬中敌敌畏残留的现场初步筛查。     

试纸法快速检测果蔬中敌敌畏含量的研究

基于比色法原理,以定量滤纸为纸基,以间苯二酚溶液为显色剂,研制出一种快速检测果蔬中有机磷农药敌敌畏的试纸。结果表明,此方法的检出限为12.5 mg/kg,检测时间仅需5 min。该试纸法具有成本低、耗时短、操作简单、携带方便等优点,适合于果蔬中敌敌畏残留的现场初步筛查。     

牛奶中抗生素快速检测试纸的研制

制作了牛奶中抗生素的快速检测试纸。探讨了TTC浓度、菌液浓度、浸泡时间等条件对试纸检测结果的影响。实验结果证明,抗生素检测试纸制作的最佳条件为:将中速滤纸浸泡在2%浓度的TTC试剂中5 min,干燥30 min。应用本试纸测试市售散装牛奶和袋装牛奶中氯霉素的含量,并与国标法检测结果相比较基本一致。检测试纸具有简便、快速、成本低等优点。     

口香糖中茶多酚含量的快速测定

文章研究了简易法测定口香糖中茶多酚的含量，最佳吸收波长为274nm。该方法的平均回收率为95．1％～102．2％，相对标准偏差小于0．29％，测得口香糖样品中茶多酚含量为9．392g／kg。实验表明，简易法可应用于口香糖中茶多酚含量的测定，同时又是一种快速测定方法，易于推广。     

胶体金试纸条法快速检测纺织品中总铅和总镉含量

建立了一种基于铅、镉单克隆抗体的胶体金试纸条方法,用于快速检测纺织品中总铅、总镉含量,通过加标实验及对实际试样进行测试,探讨了试纸条的灵敏度、准确性和稳定性.结果表明:制备胶体金试纸条时,铅、镉单克隆抗体较佳用量分别为50,45μL;试纸条对纺织品中总铅及总镉含量的检出限分别达5.0 mg/kg和0.625 mg/kg...     

试纸法快速检测工业废水中重金属铜离子

介绍了一种可以快速、便捷、灵敏地进行现场半定量和定量测定水体中重金属Cu2+浓度的络天青-氨基化纤维素试纸。该试纸的检出限为0.1 mg/L,在pH值为6.0⁷.0时,检测的线性范围为0.17.0时,检测的线性范围为0.1¹0.0 mg/L,反应时间为120 s。该方法可与微型光谱仪或Cu2+标准比色板联用,可以同时进行定量或者半定量检测。该试纸弥补了显色剂易从试纸上脱落的不足,增强了试纸的稳定性与准确性。该方法可应用于工业废水中Cu2+的测定,与原子吸收分光光度法的测定结果相比较,两者基本一致。     

三聚氰胺快速检测试纸条评价

胶体金试纸条因其方法简便、快速,已经广泛应用于日常检测和实验研究中.为了解国产三聚氰胺试纸条的有效性和可靠性,选择了一种市售试纸条,从灵敏度、特异性、准确度、耐变性、批间变异等多个角度对其进行了技术评价.结果发现用胶体金法测定牛奶中的三聚氰胺,检测限为0.05 mg/L,特异性、耐变性较好,批件差异较小,不同基质对检测结果无影响.此试纸条满足食品中有毒有害物质快速检测的要求,可作商品化快速检测试纸条使用.     

试纸法快速测定溶液中的银离子

用重金属离子含量低的定量滤纸，依次在硝酸镉、硫化钠溶液中浸渍，晾干后，用于测定溶液中Ａｇ＋。Ａｇ＋浓度在０～１０ｇ／Ｌ时，直接用色阶比较法，检出限０．２９／Ｌ；Ａｇ＋含量低于０．１ｇ／Ｌ时，可使用简单微型装置，２０ｍｌ样品的检出限可达０．２５ｍｇ／Ｌ。几种测定方法比较，结果一致。     

试纸法快速测定锅炉水中磷酸盐的研究

通过大量实验,研制出了一种适合工业锅炉水磷酸盐的快速测定试纸.该试纸浸入含有磷酸根的水溶液后,再滴加显色剂在试纸上会发生显色反应,利用显色深浅与磷含量的关系,直接比色测定水溶液中磷酸盐含量.通过实验筛选出最佳测定条件,以高分子材料作为表面活性剂浸纸,使显色均匀、集中,有助于灵敏度的提高.     

试纸法快速检测茶叶中铅含量的研究

基于重金属与三苯甲烷类碱性染料显色反应的特征,以定量滤纸为纸基,孔雀石绿为显色剂,研制出一种快速检测茶叶中铅含量的试纸。结果表明,试纸最低检出限为30 mg/L,检测时间仅需5 min,保质期在30 d左右。用本试纸测定茶叶中的铅含量,并与分光光度法进行比较,结果大致吻合。此法具有成本低、操作简单快速、携带方便等优点,可用于茶叶以及其它食品中重金属铅的现场初步筛查。     

试纸法快速检测茶叶中铅含量的研究

基于重金属与三苯甲烷类碱性染料显色反应的特征,以定量滤纸为纸基,孔雀石绿为显色剂,研制出一种快速检测茶叶中铅含量的试纸。结果表明,试纸最低检出限为30 mg/L,检测时间仅需5 min,保质期在30 d左右。用本试纸测定茶叶中的铅含量,并与分光光度法进行比较,结果大致吻合。此法具有成本低、操作简单快速、携带方便等优点,可用于茶叶以及其它食品中重金属铅的现场初步筛查。     

Study on the microwave-assisted extraction of polyphenols from tea

This study demonstrated a promising method for quickly extracting tea polyphenol (TP) by microwave-assisted extraction (MAE) technology. Some influential parameters, including MAE temperature, microwave power, concentration of extraction solvent, MAE time and the solid/liquid ratio, were investigated. The optimum condition of MAE was obtained by dual extraction with 60% ethanol (v/v) and the solid/liquid ratio 1:12 g/mL at 80°C for 10 minutes under the microwave power 600W. The yield of TP was 96.5% under the described condition. Compared with traditional methods, including hot reflux extraction (HRE), ultrasound-assisted extraction (UAE) and supercritical fluid extraction (SFE), the extraction time was saved 8 times than that of HRE, and the yield was increased by 17.5%. The extraction time at comparable levels of production was saved 2 times, and the energy consumption was one fourth that of UAE. The extraction time was saved 5 times than that of SFE, and the yield of TP was increased by 40%. Moreover, compared with MAE of TP studied by others, it decreased the solid/liquid ratio from 1: 20 to 1: 12 g/mL without 90-min pre-leaching time, and the yield of TP was increased by 6%–40%.     

Study on the microwave-assisted extraction of polyphenols from tea

This study demonstrated a promising method for quickly extracting tea polyphenol (TP) by microwave-assisted extraction (MAE) technology. Some influential parameters, including MAE temperature, microwave power, concentration of extraction solvent, MAE time and the solid/liquid ratio, were investigated. The optimum condition of MAE was obtained by dual extraction with 60% ethanol (v/v) and the solid/liquid ratio 1:12 g/mL at 80°C for 10 minutes under the microwave power 600 W. The yield of TP was 96.5% under the described condition. Compared with traditional methods, including hot reflux extraction (HRE), ultrasound-assisted extraction (UAE) and supercritical fluid extraction (SFE), the extraction time was saved 8 times than that of HRE, and the yield was increased by 17.5%. The extraction time at comparable levels of production was saved 2 times, and the energy consumption was one fourth that of UAE. The extraction time was saved 5 times than that of SFE, and the yield of TP was increased by 40%. Moreover, compared with MAE of TP studied by others, it decreased the solid/liquid ratio from 1 ∶ 20 to 1 ∶ 12 g/mL without 90-min pre-leaching time, and the yield of TP was increased by 6%–40%.     

Synthesis of silver nanoparticles in electrospun polyacrylonitrile nanofibers using tea polyphenols as the reductant

Uniformly dispersed Ag nanoparticles (AgNPs) with diameter about 5 nm embedded in electrospun polyacrylonitrile (PAN) nanofibers were synthesized by using tea polyphenols (TP) as the reductant. The reducing ability of TP toward Ag ions was characterized by Fourier transform infrared spectroscopy and ultraviolet–visible spectra, and the results revealed that TP exhibit satisfied reducing ability in the synthesis process. Transmission electron microscopy observation showed that the synthesized spherical AgNPs with diameter about 5 nm were immobilized on the surface and in the interior of PAN nanofibers by electrospinning technology. The interactions of Ag with PAN and TP were investigated by X‐ray photoelectron spectroscopy (XPS), and the results suggested that PAN polymer and TP both served as stabilizer during the synthesis of AgNPs because of the chelating interactions of Ag with cyano groups and phenolic hydroxyls. The synthesized AgNPs in PAN nanofibers exhibit good antibacterial property and may be used for antibacterial and catalytic applications. POLYM. ENG. SCI., 2013. © 2012 Society of Plastics Engineers     

亚硝酸根试纸的开发与研制

本文通过实验确定了一种检测亚硝酸根含量试纸的制备方法。通过实验确定了试纸的材料和显色剂，并对显色剂制备过程中的影响因素进行了分析．实验结果表明：定性中速滤纸可以作为亚硝酸根试纸的材料；含有4-氨基苯磺酰胺和N-1-萘基乙二胺盐酸盐的显色剂A及含有1：1的α-萘胺溶液和对氨基苯磺酸溶液的显色剂B，按1：1混合后可以作为显色剂；通过应用实验表明，亚硝酸根试纸具有体积小、便于携带、检测方便、成本低廉等特点。因此，具有广泛的应用价值和市场开发前景。