反相流动注射法测定啤酒中单宁的研究

反相流动注射法是一种快速、简便、精确,自动化操作的方法。在碱性（pH12的Na2B4O7-NaOH缓冲溶液）条件下,单宁能还原磷钨酸生成蓝色化合物在700nm有最大吸收峰。在最优的试验条件下,单宁浓度为0～10．0mg／L范围内峰高与浓度成线性关系,其线性相关系数为0．9996,方法检出限DL=16．8μg／L,精密度RSD=0．66％（n=12）。应用于实际啤酒样品中单宁的检测,加标回收率在99．25％－100．07％之间,具有较好的重现性和准确性;与标准分析方法比较,测定结果令人满意。     

Spectrophotometric determination of iodate in iodised salt by flow injection analysis

A simple and sensitive flow injection (FI) method for the determination of iodate is proposed. The method is based on the reaction of iodate with hydroxylamine in acidic solution. Sulfanilamide is diazotised by the nascent nitrite and the diazonium ion produced is then coupled with N-(1-naphthyl)ethyenediamine in hydrochloric acid medium to form an azo dye which is measured spectrophotometrically. The calibration graph for iodate is linear in the range of 0.1–30 mg L⁻¹ with a correlation coefficient of 0.9992. The limit of detection and relative standard deviation are 0.02 mg L⁻¹ and 1.2% (5 mg L⁻¹, n = 8). The method has been applied to the determination of iodate in table salts and accuracy was assessed through recovery experiments and independent analysis by a conventional titrimetric method.     

An optical flow injection analysis system for measurement of glucose in tomato

An optical flow injection analysis (FIA) system for glucose measurement in tomato was constructed by using a glucose oxidase (GOD) immobilized reactor and a photodiode sensor, a peristaltic pump and a personal computer. The GOD reactor was crammed with strip-shaped of a GOD immobilized membrane to an acrylic pipe. The GOD was immobilized on polytetrafluoroethylene membrane by crosslinking with glutaraldehyde. Hydrogen peroxide generated by the GOD reaction oxidized luminol to produce chemiluminescence in the presence of horseradish peroxide. The chemiluminescence was detected by using the photodiode. The glucose measurement system was calibrated with standard glucose solutions. The calibration range of the system for glucose was 2.0–100.0 mmol L⁻¹. Measurement time for every sample was within 3 min. Glucose concentrations of a fresh and processed tomato samples measured with this glucose measurement system could be evaluated rapidly and non-laboriously.     

快速检测食品中有机磷及氨基甲酸酯类农药的流动注射式酶传感器

介绍一种快速检测有机磷及氨基甲酸酯类农药的流动注射式酶传感器,该系统由蠕动泵、流动注射进样阀、酶柱、比色反应盘管、恒温水浴、吸光度检测器和数据采集的计算机构成。通过对流动注射的流出曲线分析,对底物浓度、反应温度进行优化,并对黄瓜和鸡毛菜中的农药进行检测。结果发现,160mmol/L的底物浓度和40℃为最佳反应参数。该系统检测具有较好的重现性,可检出0.5mg有机磷/kg果蔬和0.5mg氨基甲酸酯类农药/kg果蔬,整个检测过程仅需12min。     

Chemiluminescence microflow injection analysis system on a chip for the determination of nitrite in food

A new microflow injection analysis (μFIA) system on a chip for the determination of nitrite is described. The chip is produced by using two transparent poly(methylmethacrylate) (PMMA) slices measured 50 × 40 × 5 mm, and the microchannels etched by CO₂ laser are 200 μm wide and 100 μm deep with the volume of reaction area about 1.8 μL. Nitrite is sensed by the chemiluminescence (CL) reaction of luminol with ferricyanide that is the product of the reaction of ferrocyanide with nitrite in acidic medium. The syringe pump with an accurate timer controls all reagents, including the sample. The linear range of the nitrite concentration is 8–100 μg L⁻¹ and the detection limit is 4 μg L⁻¹ (S/N = 3). The proposed method has good reproducibility with the relative standard deviation 4.1% for 50 μg L⁻¹ of nitrite (n = 9) and is very sensitive and simple. It has been successfully applied to the determination of nitrite in food.     

流动注射分析系统的发展及其在过程 监控中的应用

过程监控能为过程控制及质量控制提供及时且有价值的信息。发展自动化的在线分析系统是实现过程监控的关键。流动注射技术的发展提高了分析仪器的自动化和智能化水平, 流动注射在线分析系统具有分析速度快、样品和试剂消耗少, 不仅可以实现样品的在线检测, 而且还能实现样品的在线前处理, 因此在过程分析中得到了广泛应用, 甚至成为了实现过程分析的必要技术手段。发展性能优异的流动注射分析系统而满足不同的过程分析, 是国内外的热点研究课题。本文的目的是通过综述流动注射分析系统的发展, 及其在食品加工过程监控、发酵过程监控和化学反应过程监控中的应用研究进展, 强调发展新型流动注射分析系统对于过程分析的重要性, 并期待能进一步推动这方面工作的开展。     

Determination of melamine by flow injection analysis based on chemiluminescence system

In this paper, based upon the phenomenon that melamine can obviously enhance the CL signal of the luminol–H₂O₂ system in basic medium, a simple, rapid and sensitive flow injection chemiluminescence (FI-CL) method for the determination of melamine has been developed. Under the optimum conditions, the linear range for the determination of melamine was 0.2–80 μg mL⁻¹ with a detection limit of 0.12 μg mL⁻¹ calculated as proposed by IUPAC and a relative standard deviation of 3.26% for 11 solutions of 10 μg mL⁻¹ melamine on the same day. The proposed method was satisfactorily applied to determine melamine in milk-based products and satisfactory results were obtained without interferences from the sample matrix. Moreover, one assay produce takes only 25 s and the minimum sampling rate is about 120 samples h⁻¹, which indicated that the FI-CL method was suitable for high throughput and real-time melamine analysis.     

流动注射——光度法在环境监测中的发展应用

随着我国经济的发展和技术水平的提升,环境监测工作越来越受到重视.流动注射-光度法是一种新型的微量、高速和自动化的分析技术,可以在环境监测中发挥重要作用,有效提升环境质量.本文就流动注射-光度法在环境监测中的发展应用进行分析,为相关部门进行相关工作时提供参考.     

Review: Flow injection analysis–a new technique for food and beverage analysis

Flow injection analysis affords a means of automating many traditional wet chemical methods of food and beverage analysis, and introducing new methods which have no conventional analogue. In this technique, reactions are carried out in a continuous flow mode and it is not necessary for a state of chemical equilibrium to be reached. Therefore, analyses using standard or official chemistries may be achieved in very short times (typically 30 sec). This review outlines the principles, instrumentation and techniques of flow injection analysis and considers the scope of its actual and potential applications in food and beverage analysis.     

流动注射化学发光法在线检测饮用水中脱氧雪腐镰刀菌烯醇

为应对突发性脱氧雪腐镰刀菌烯醇污染饮用水事件的发生,基于脱氧雪腐镰刀菌烯醇对鲁米诺—过氧化氢体系的促进作用,建立流动注射化学发光在线检测脱氧雪腐镰刀菌烯醇的新方法。在优化的试验条件下,该方法测定脱氧雪腐镰刀菌烯醇的线性范围为0.001~4.000 mg/L;检出限(S/N=3)为0.001 mg/L;相对标准偏差(RSD,n=11)为1.89%;不同加标水平下的加标回收率为67.33%~94.50%;相对标准偏差(n=3)小于2.34%。该方法具有灵敏度高、分析速度快及操作简便等优点,可应用于突发性脱氧雪腐镰刀菌烯醇污染的在线快速检测和应急预警。     

Rapid determination of picogram levels of patulin in apple juice using a flow injection chemiluminescence procedure

BACKGROUND: A sensitive, rapid and simple chemiluminescence procedure, based on the enhancing effect of patulin on the chemiluminescence (CL) reaction between luminol and hydrogen peroxide in a flow injection (FI) system, has been proposed for the determination of patulin. RESULT: The increment of CL intensity was linear over the concentration of patulin ranging from 0.05 to 80 ng mL^?1, with a detection limit (3S/N) of 0.01 ng mL^?1. At a flow rate of 2.0 mL min^?1, a complete analysis could be performed in 25 s with a relative standard deviation of less than 4.0%. CONCLUSION: The proposed method was successfully applied to the measurement of apple juice samples obtained from the Shaanxi Entry–Exit Inspection and Quarantine Bureau. The recoveries were between 93.4 and 107.9% Copyright © 2008 Society of Chemical Industry     

流动注射化学发光法在线检测饮用水中的3-硝基丙酸

利用碱性条件下3-硝基丙酸对鲁米诺—高锰酸钾化学发光体系有显著的抑制作用,结合流动注射分析技术,建立了一种在线检测饮用水中3-硝基丙酸的流动注射化学发光新方法。在优化的试验条件下,其线性范围为1~150mg/L,方法的检出限为0.28 mg/L,相对标准偏差为1.9%,3-硝基丙酸加标回收率为76.5%~93.8%。该方法具有较好的准确性和选取性,可实现饮用水中3-硝基丙酸的快速在线检测。     

Determination of bromate in bread additives and flours by flow injection analysis

A new, simple, rapid and sensitive spectrophotometric flow injection analysis (FIA) method was developed for the determination of bromate based on its reaction with 3,5-dibromo-PADAP and thiocyanate in a strongly acidic medium. This produced an unstable violet product with a maximum absorption at 602 nm. The calibration curve was linear in the range of 2.00×10⁻⁶–2.10×10⁻⁵ mol/l and the detection limit was 8.00×10⁻⁷ mol/l. The sampling frequency was 90 h⁻¹. The method has been successfully applied to the determination of bromate in commercial bread additives and flours.     

Determination of trimethylamine nitrogen and total volatile basic nitrogen in fresh fish by flow injection analysis

There are many chemical, microbiological and sensory indices of fish quality. Of the chemical indices, TMA-N and TVB-N are probably the most used in connection with remaining shelf-life determination. This paper reports on a study of modifications to a flow injection analysis (FIA) method necessary to make it suitable for TMA-N and TVB-N determination, specifically the optimal concentrations of NaOH and formaldehyde for releasing the volatile bases from the acidic fish extract and sequestering the non-TMA volatile bases respectively. The effects of using perchloric acid (PCA) and trichloroacetic acid (TCA) as fish extractants were also investigated. The fish species used were monkfish (Lophius piscatorius), skate (Raia clavata) and cod (Gadus morrhua). It was found that 1 M NaOH was the optimal concentration for volatile base release and that 200 g l⁻¹ formaldehyde was adequate for non-TMA base sequestration. Use of PCA and TCA as fish extractants appeared to have no significant effect on TMA-N and TVB-N determinations. © 1999 Society of Chemical Industry     

Determination of preservatives in meat products by flow injection analysis (FIA)

Various preservatives are added to meat products to extend shelf-life and enhance food safety; thus, their determination is essential for legislative purposes and consumer health. Analytical methodologies based on flow injection analysis (FIA) offer attractive advantages compared with other procedures, such as versatility, precision, low cost, speed and ease of automation. This review considers the status of published FIA methodologies for the determination of preservatives in meat products. The techniques are described regarding their application to different preservatives (nitrates and nitrites, sulfites, sorbates, benzoates and p-hydroxybenzoate esters), with emphasis on extraction, separation, detection and quantification procedures in meat matrices.     

流动注射荧光法测定植物油中脂肪醛

建立了流动注射荧光法测定食用植物油中脂肪醛化合物的方法。利用2-萘肼和脂肪醛化合物在酸催化作用下生成在400 nm波长处有强荧光发射的2-萘腙化合物的原理,在自制的流动注射分析仪中,以混合醛（甲醛、乙醛、正丙醛、正丁醛、正戊醛、正己醛、正庚醛、正辛醛、正壬醛）为标准物质,对催化剂、温度、时间、溶剂、2-萘肼的浓度和载流流速进行了条件优化,确定了最佳的流动注射荧光法检测食用植物油中脂肪醛化合物的方法。在该优化条件下,脂肪醛化合物测定的线性工作曲线为y=26.8x+42,相关系数0.997;该方法的相对标准偏差（RSD）在1.18%¹.89%之间,回收率在92%¹13%之间,最低检出限为0.02 mmol/L（S/N=3）。因此,流动注射化学发光法具有方法简单、检测快速、数据准确等特点,可用于实际食用油样品中醛类物质的在线快速检测。      

Application of flow injection analysis for determining sulphites in food and beverages: A review

Sulphites have been widely used as preservatives in food and beverages. Preservative determination is essential for the purposes of legislation and consumer safety. Among the analytical methodologies available, those based on flow injection analysis (FIA) can be highlighted. FIA offers interesting advantages such as versatility, accuracy, low cost, speed and automation, among others. These advantages make FIA an important alternative to conventional methods. This review considers the present status of published FIA methodology for determining sulphites in food and beverages. A detailed analysis of the technique is done, stressing its impact on the aspects of the extraction, separation, detection and quantification procedures in different matrices.     

食用油脂过氧化值流动注射分析仪研制

建立流动注射食用油脂过氧化值测定方法。基于流动注射分析—分光光度比色法研制了一种食用油脂过氧化值流动注射分析仪,研制了电动变向三通道液流阀和微恒流泵;阀控制载液流向,三个溶液开关的九个溶液孔在阀体同一圆周上,占用空间小,阀体旋转三十度即可实现三种载液同时换向;泵控制样品溶液注入,旋桨旋转后在锥形圆台腔可形成高压溶液区,转动不接触无磨损,死体积小。方法的线性范围为5~170μmol/L,线性相关系数为0.9995,检出限为3.57μmol/L,回收率在93%~104%之间。本方法用于快速检测菜籽油、循环火锅油和回收油的过氧化值,对本方法和国标方法的测定结果进行t检验分析,两种方法检测结果无显著性差异。