铜离子荧光探针研究进展

设计和开发高选择性和超灵敏的铜离子荧光探针对于检测对生命活动有重大作用的铜微量元素具有重要意义。根据分子荧光分子探针的识别机制和结构特点,综述近年来铜离子荧光探针的研究进展。     

铜离子的荧光纳米检测方法研究进展

铜是生命体的必需营养素,也是典型的环境污染物,因此对生命体和水体中的铜进行高灵敏度和高选择性的检测对于食品安全、环境监测、临床诊断具有重要意义.在众多检测方法中,纳米材料的荧光检测因具有高灵敏度、响应迅速、简便性、低成本和易于操作等优势已成为近年来的研究热点.本文综述了铜离子纳米荧光探针的制备、机理、性能及应用,展望了...     

荧光探针在高通量筛选技术上的应用进展

荧光探针是一种分析检测工具,针对特定的化学物质可以将微观的识别信息转化为宏观的荧光信号,具有高灵敏度、高选择性、检测体系干扰小、操作简便等优点。基于荧光探针的优势,其在高通量筛选技术领域有着重要的应用。该文主要综述了荧光探针的起源、作用机理以及国内外关于荧光探针在高通量筛选技术上的应用进展,旨在为拓宽荧光探针技术的应用领域,推动高通量筛选技术发展提供参考。     

基于多肽识别基团的荧光探针及其对食品中氰化物的检测

以7-二乙胺基香豆素-3-羧酸、甘氨酸、组氨酸为原料,采用标准多肽合成法成功合成了水溶性的荧光探针分子香豆素—甘氨酸-甘氨酸-组氨酸(Coumarin—Gly-Gly-His,CGGH),利用GGH三肽对Cu~(2+)的络合作用形成C-GGHCu~(2+)络合物,使探针分子C-GGH的荧光猝灭;然后,通过向体系中加入氰化物后,CN~-对Cu~(2+)的强络合作用形成稳定的络合物[Cu(CN)_x]而使探针分子荧光逐渐恢复,以此实现对氰化物的定量检测。该法检测限为0.015μmol/L,远低于国家标准(GB 8537—2008)中要求最严的矿泉水中氰化物的限量值0.01mg/L(相当于摩尔浓度0.385μmol/L),该探针分子对CN~-的检测不受SCN~-、F~-、Cl~-、Br~-、I~-、PO_4~(3-)、N~(3-)、NO_3~-、AcO~-、SO_4~(2-)、CO_3~(2-)等共存阴离子的影响。经对实际食物样品中氰化物进行检测,证明该方法的准确度与国标(GB/T 5009.48—2003、GB/T 5009.36—2003、GB/T8538—2008)方法一致,且更快捷、简单。     

新型荧光探针制备及茶叶中汞离子检测的研究

以S-亚硝基谷胱甘肽（GSNO）作为保护剂和还原剂合成了水溶性金纳米团簇AuNCs,建立了分析实际茶叶样品中汞离子（Hg2+）高灵敏的方法。通过透射电镜（TEM）、动态光散射仪（DLS）、紫外-可见吸收光谱（UV-VIS）和荧光光谱对所制备的S-亚硝基谷胱甘肽包被的金纳米团簇GSNO@AuNCs进行了表征,随着汞离子浓度的增加,体系的荧光被高效猝灭,以此构建了检测汞离子的荧光探针。探讨了pH值、盐离子浓度、反应时间和温度对其荧光性能的影响。在优化实验条件下,汞离子浓度在0.1～40.0 μmol/L范围内与GSNO@AuNCs的荧光强度呈良好的线性关系,线性回归方程为Y=1.392+27.28X,相关系数R2=0.999 5,检出限为0.033 μmol/L。同时初步构建了GSNO@AuNCs荧光探针应用于茶叶样品中汞离子的检测,结果满意。     

一种新型基于罗丹明B选择性检测食品中铬离子的荧光探针的研究

文章设计合成了一种新型基于罗丹明B的增强型荧光探针以定性定量检测Cr3+。探针通过1H、13C和LC-MS进行结构表征，利用荧光分光光度法对光谱特性进行研究。结果表明，在乙腈溶液中，探针可选择性识别Cr3+，诱发肉眼可见的颜色变化（从无色变为亮粉色）以及剧烈的荧光开启（81904.30倍）。反应时间为4 min，检测限可达0.059μmol/L。此外，探针在实际样品检测中也表现良好，加标回收率为100.21%～100.69%。     

CdTe量子点作为荧光探针检测皮蛋中微量铜

基于CdTe量子点作为荧光探针建立了一种定量检测皮蛋中微量铜（Cu2＋）的荧光分析法。采用巯基乙酸和1-硫丙三醇作为稳定剂,水相中快速制得荧光性好、稳定性好的水溶性CdTe量子点,并运用紫外-可见分光光度和荧光光谱法研究CdTe量子点的发光特性。实验探究了Cu2＋对CdTe量子点荧光猝灭的机理,并根据Cu2＋浓度和荧光强度下降量之间的关系,在Cu2＋浓度范围为10～200 nmol/L时建立定量检测微量Cu2＋的线性方程,相关系数高达0.997,检出限低至0.96 nmol/L。本实验方法已经初步应用于皮蛋样品中Cu2＋的检测,结果显示相对标准偏差在1.47%～3.01%之间,回收率为104%～108%,说明了此方法的准确性、可靠性和适用性。     

荧光探针技术在谷胱甘肽检测中的应用

谷胱甘肽(glutathione,GSH)是细胞与组织内重要的活性小分子,在工业生产领域有着广泛的应用.谷胱甘肽具有重要的生产以及研究价值,因此如何对其进行高效且专一地检测已成为当前谷胱甘肽工业生产及其功能研究的重要课题.荧光探针作为一种新型的检测手段,具有灵敏度高、专一性强以及制备成本低等优点,被广泛应用于各类小分子检测.近年来,已经有诸多检测谷胱甘肽的荧光探针被报道,且均表现出良好的检测性能.对近些年来不同类型的谷胱甘肽探针进行综述并对其机理进行简要介绍.     

荧光探针在食品中甲醛检测的最新应用进展

甲醛是一种高活性的小分子,具有环境毒性,对人体可以带来不可逆损伤。荧光探针法具有设备简单、操作简便、高灵敏度、高选择性等优点,在生物成像、生物体外检测等领域具有应用优势。在食品检测领域,尤其面对快速检测的需求日趋增长,荧光探针法,包括有机小分子荧光探针、纳米荧光探针、金属有机骨架探针等,为甲醛的痕量和快速检测提供了方法和平台,得到了不断关注和飞速发展。本文主要从反应机理和结构的角度,从有机小分子荧光探针、纳米荧光探针、金属有机骨架荧光探针3个方面介绍和讨论了近年来荧光探针法在食品中甲醛检测的应用进展,总结了不同类型荧光探针方法的特点和应用效果,为荧光探针法在食品快速检测领域的应用持续优化提供新的角度和思考。     

智能手机辅助铜纳米簇/金属有机框架杂化荧光探针检测小白菜中的百草枯

目的 基于铜纳米簇(coppernanoclusters,CuNCs)/金属有机框架(metal-organicframeworks,MOF)复合材料谷胱甘肽(glutathione, GSH)-CuNCs/Al-MOF构建一种智能检测小白菜中百草枯的快速、简便的方法。方法 利用化学还原法和溶剂热法制备由GSH修饰的GSH-CuNCs和Al-MOF,合成新型荧光传感材料GSH-CuNCs/Al-MOF,并构建一种比率型荧光检测方法。通过百草枯和GSH-Cu NCs的电子转移和静电相互作用, GSH-CuNCs聚集荧光发生淬灭,而Al-MOF的荧光强度在整个过程中保持不变,复合探针的荧光强度比率反映百草枯的浓度。结果 百草枯在5～100μmol/L范围内线性关系良好,检出限为1.4μmol/L,检测时间为7～15min,选择性和抗干扰能力良好。利用智能手机RGB识别可视化定量检测百草枯,检出限为4.4μmol/L。方法可用于小白菜中百草枯的检测,回收率为96.05%～106.30%。结论 该方法首次实现对百草枯的比率荧光智能检测,具有快速、简便、低成本等特点,为联吡啶类除草剂的检测提供研...     

离子色谱-双波长紫外检测法同时测定水中碘酸盐和碘离子的含量

目的建立离子色谱-双波长紫外检测法同时测定水中碘酸盐和碘离子的分析方法。方法水样过0.22μm滤膜后直接进样测定,水中碘酸根和碘离子通过离子色谱柱分离,紫外检测器分别在200nm和226nm处检测。结果碘酸根和碘离子在0.01~1.00mg/L浓度范围内线性良好,相关系数r分别为0.99953和0.99950,检出限为0.004和0.005mg/L,相对标准偏差(relative standard deviations,RSDs)为2.8%和2.7%(n=8)。低(0.05mg/L)、中(0.10mg/L)、高(0.50mg/L)3个浓度IO_3~-和I~-加标回收率范围为94%~106%和92%~102%,精密度为1.04%~4.82%和0.75%~4.47%。结论本方法操作简单、准确度高、精密度好、线性范围宽,适用于水中碘酸盐和碘离子的测定。     

Sorption of copper (II) ions by pine sawdust

The sawdust of Calabrian pine was used as sorbent for the removal of Cu(II) ions from aqueous solution of copper sulfate pentahydrate (CuSO₄.5H₂O) at different concentrations, pHs and temperatures. The results showed that about 65–81% of Cu(II) ions in the solution could be adsorbed on the sawdust. The percentage of adsorped Cu(II) ions onto the sawdust increased with increasing initial concentration. Kinetic studies indicated that the sorption process followed the first order reversible kinetic model. It was also determined that the sorption process obeyed the Freundlich isotherm. Furthermore, the sorption thermodynamic was investigated in detail.     

Rapid method for detection and detoxification of heavy metal ions in water environments using phytochelation

Phytochelatins (PCs, (gammaGlu-Cys)n-Gly (n = 2-11)) are produced by higher plants, algae, and some fungi in response to heavy metal ion exposure. A rapid and convenient method for quantifying heavy metal ion concentrations in water environments was developed using a chemically synthesized PC as a mediator. The chelating ability of the PC and quantification of the thiol group were utilized to measure heavy metal ions at low concentrations. The method requires only ten minutes for measurement and only 1 ml of a liquid sample. A range of homogeneous PCs (n = 4-7) were chemically synthesized using a peptide synthesizer. These, especially PC7, exhibited higher sensitivity and consistency of measurement than the native PC from Silene cucubalus, which produced a mixture of PC2, PC3, and PC4. Detoxification of heavy metal ions in vitro by PC was also investigated. Using the paper disc method, the cell growth inhibition zone caused by cadmium ion against Salmonella typhimurium TA1538 was significantly decreased by addition of PC. Furthermore, at the minimum inhibitory concentration of cadmium ion (200 microM) in a nutrient broth culture of S. typhimurium, cell growth was almost completely recovered by addition of PC to the medium.     

曙红探针光度法检测鸡肉与鸡蛋中残留恩诺沙星

以曙红为探针,利用其与恩诺沙星形成的新缔合物的光学性质,实现对恩诺沙星的准确且灵敏检测。在酸性条件下,恩诺沙星与曙红相互反应而形成的新缔合物使曙红的最大吸收波长从514 nm红移至520 nm处,且520 nm波长处的吸光度随着恩诺沙星浓度的增加而减小。基于此而建立了一种曙红探针光度法检测恩诺沙星含量的新方法。在优化的实验条件下,恩诺沙星浓度在0. 08～10. 0 g/mL范围内与体系在520 nm处的吸光度呈良好的线性关系(R~2=0. 992 4),方法的检出限与定量限分别为0. 05 g/mL、0. 08 g/mL。对1. 0 g/mL的恩诺沙星进行连续8次测定,其RSD为4. 9%。利用本方法对鸡肉与鸡蛋中恩诺沙星含量进行测定并做回收率实验,平均回收率分别为93. 61%与92. 17%。该方法有望为食品监督部门提供一种测定食品中恩诺沙星含量的新途径。     

Hexanal as biomarker for milk oxidative stress induced by copper ions

Milk flavor varies greatly due to oxidative stress during storage. Several studies have documented the use of volatile biomarkers for determining milk oxidation, but only a few have focused on the development of inline procedures enabling the monitoring of milk oxidative stress. In this work, oxidative stress was induced in pasteurized milk samples by spiking increasing concentrations of copper ions (from 0 to 32 mg·L^?1). During storage (4°C), hexanal evolution was monitored by a proton transfer reaction mass spectrometer. The mass fragment m/z 83 was selected as a biomarker for hexanal determination. Its intensity evolved with a sigmoidal trend, showing a maximum rate proportional to the Cu²⁺ content in milk. The proposed approach is simple, fast (up to 120 sample/h), sensitive (8.8 μg·m^?3 per μM hexanal in the sample), with low limit of detection (0.5 μM, determined as 3 times the standard deviation divided by the slope of a calibration line), precise (<6%), with good recovery (99–104%), and noninvasive. The method can be used for laboratory screening of milk susceptibility toward oxidation or for quality control in the processing line.     

High-throughput determination of citrinin in rice by ultra-high-performance liquid chromatography and fluorescence detection (UHPLC-FL)

A rapid, simple and effective method for the determination of citrinin in rice by UHPLC coupled to fluorescence detection has been developed and validated. Extraction of citrinin from rice samples was achieved by applying a QuEChERS-based extraction/partitioning process with water and acetonitrile, without the need of further extract clean-up. The method was fully validated for white rice, and its applicability in other rice matrices, such as brown and red rice, was confirmed by recovery experiments. Under optimum conditions, recoveries ranged from 72.5% to 92.8%, with relative standard deviations (RSDs) lower than 7.1%. Detection and quantification limits were estimated to be 1.5 and 5.0 µg kg^?1, respectively. Finally, 21 organic rice samples were analysed, but none was contaminated with citrinin above the detection limit of the method. The method proved to be fast and non-laborious.     

毛细管电泳在多肽分离和检测中的应用

分析了毛细管电泳的基本原理、分离模式及检测技术，从多肽的分离、纯度鉴定、结构分析、等电点测定、定量检测等方面综述了毛细管电泳在多肽分析中的最新研究进展。     

丽春红S探针双波长吸收光谱法测定食品中的Cu

文中建立了测定食品中Cu的二元双波长可见吸收光谱(DWO-VIS)法。在pH 6.86的Tris-盐酸缓冲介质中,丽春红S与Cu(Ⅱ)发生反应,在可见光区生成具有一个明显正吸收峰和一个明显负吸收峰的离子缔合物。最大正吸收波长和最大负吸收波长分别为445 nm和510 nm。Cu(Ⅱ)在0.06~1.6 mg/L(正吸收,445 nm)、0.04~1.6 mg/L(负吸收,510 nm)和0.03~1.6 mg/L(DWO-VIS,445 nm+510 nm)内遵从朗伯-比尔定律,表观摩尔吸光系数(κ)分别为8.70×10~3(正吸收法)、2.04×10~4(负吸收法)和2.92×10~4(DWO-VIS法)L/(mol·cm),定量限分别为0.62、0.38和0.26 mg/100 g。还探讨了吸收光谱特征、适宜反应条件及共存物质的影响。双波长法用于饼干、面条及奶粉中Cu的测定,加标回收率为97.9%~102%,相对标准偏差RSD(n=5)为2.5%~2.8%。