Application of amperometric sol-gel biosensor to flow injection determination of glucose

A glucose biosensor with enzyme immobilised by sol–gel technology was constructed and evaluated. The glucose biosensor reported is based on encapsulated GOX within a sol–gel glass, prepared with 3-aminopropyltriethoxy silane, 2-(3,4-epoxycyclohexyl)-ethyltrimetoxy silane and HCl. A flow system incorporating the amperometric biosensor constructed was developed for the determination of glucose in the 1×10⁻⁴–5×10⁻³ mol l⁻¹ range with a precision of 1.5%. The results obtained for the analysis of electrolytic solution for iv administration and human serum samples showed good agreement between the proposed method and the reference procedure, with relative error <5%.     

流动注射在线共沉淀预富集火焰原子吸收法测定痕量铜

研究了以Ｎｉ＾２＋－ＤＤＴＣ为共沉淀载体，流动注射在线共沉淀预富集－火焰原子吸收光谱法测定痕量铜的体系，在０．３ｍｏｌ．Ｌ＾－１的硝酸介质中，铜离子在编织反应器中与Ｎｉ＾２＋－ＤＤＴＣ（产生共沉淀，并被收集在编织器内壁上，用甲基异丁基酮（ＭＩＢＫ）在线洗脱沉积物并引入火争原子化器中测定。当富集时间为４０ｓ时，４０μｇ．Ｌ＾－１的铜１０次测定的相对标准偏差为３．０％，灵敏度提高６０倍，检出限（３σ）     

纳米CoHCF修饰电极的制备及其对血红蛋白的电化学测定研究

A cobalt hexacyanoferrate （CoHCF） nanoparticle （size ca. 60 nm） chemically modified electrode （CME） was fabricated and the electrochemical behavior of hemoglobin （Hb） at this nanosized CoHCF CME was studied. In comparison with a bare glassy carbon electrode （GCE） and a general CoHCF CME electrodeposited in a traditional manner, the present nanosized CoHCF CME performed efficiently electrocatalytic reduction for Hb with relatively high sensitivity, stability, and longlife, Combined with liquid chromatography （LC）, the nanosized CoHCF CME was used as the electrochemical detector of Hb in the established flow injection analysis-electrochemical determination （FIA-ECD） system. The peak current was a linear function of concentrations in the range from 2.5×10^-8 to 5.0×10^-6mol/L for Hb, with detection limit of 1.4×10^-8 mol/L. The FIA-ECD system has been successfully applied to assess the Hb content of clinic blood samples with advantages of sensitiveness, speediness, easy control and small sample-consumption.     

芯片式流通池顺序注射可更新表面反射光谱法用于酶反应检测

将芯片式流通池顺序注射可更新表面反射光谱法用于酶反应检测。HRP催化H2O2氧化BPR底物的反应用于对H2O2的检测。此反应体系与葡萄糖氧化酶联用，用于对血清中葡萄糖的检测。     

电化学检测在流动注射分析中的应用

评述了近几年来电化学检测在流动注射分析中的应用，展望了流动注射电化学分析法的发展动向。     

在线液膜萃取富集流动注射分光光度法测定水中挥发酚

选用无毒性的磷酸三丁酯为流动载体，煤油为膜溶剂的液膜萃取体系，建立了液膜在线萃取富集流动注射分光光度法测定水中挥发酚的新方法。对实验条件进行了优化，在最优条件下，方法的检出限为0．0007mg/L；线性范围为0．001～0．01mg/L。应用于自来水及河水中挥发酚的检测，结果满意。     

流动注射在线萃取-火焰原子吸收法测定食用盐中的锌

基于锌与 1 (2 吡啶偶氮 ) 2 萘酚 (简称PAN)形成的配合物可被氯仿萃取 ,从高盐基体样品中分离富集锌 ,利用自行设计的分相器 ,实验确定了最佳的流动注射在线萃取 火焰原子吸收光度法测定锌的流路系统和化学反应条件。在选定的工作条件下 ,其RSD和检出限分别为 4 3 % (c=0 6 μg/mL ,n =1 1 )和0 0 3 μg/mL ,测定速度为 2 5样 /h。用于实际样品的测定 ,加标回收率为 97%～1 0 6 %。     

聚双环戊二烯反应注射成型

本文介绍了国外有关聚双环戊二烯反应注射成型的研究进展，讨论了国内进行聚双环戊二烯反应注射成型开发研究的现实意义，并对这一领域的发展进行了展望     

Spectrophotometric determination of total phenolics by solvent extraction and sorbent extraction optosensing using flow injection methodology

Flow injection analysis (FIA) procedures for the Spectrophotometric determination of phenol involving in-line concentration by solvent and sorbent extraction have been developed. The imine product formed in the reaction between phenol and 4-aminoantipyrine (4-AAP) is either extracted into chloroform (solvent extraction) or is temporarily retained on C₁₈-modified silica material contained in a microcolumn (sorbent extraction). In the latter case two variants of detection have been used namely the Spectrophotometric measurement of the methanolic eluent containing the concentrated dye and at-column optosensing of the retained reaction product followed by methanol elution to maintain reversibility of the process. In the solvent extraction procedure a 10-fold increase of sensitivity compared to the common FIA method without extraction is achieved but no corresponding improvement in detectability is observed. Under optimized conditions the detection limit amounts to 8 μg l⁻¹. Using sorbent extraction methodology, high concentration factors can be obtained when large sample volumes are used. The only limitation in getting correspondingly lower detection limits are an increasingly high and variable blank value with sampling volume. The detection limits obtained for measurement of the absorbance in the eluent and on-column optosensing are 11 μg l⁻¹ and 0.4 μg l⁻¹, respectively. A study of the extractability of various phenol derivates using both solvent and sorbent extraction revealed lower relative response rates compared to the FIA method without extraction. Phenolics that possess an additional acidic group are present in ionized form at the high pH of the assay and are not extractable at all.     

Properties and Characterization of Modified HZSM—5 Zeolites

Physicochemical and catalytic properties of phosphorus and boron modified HZSM-5 zeolites treated with 100% steam at 673K were investigated.The acidity and distribution of acidic sites were studied by infrared spectroscopy using pyridine as probe molecule and temperature programmed desortion (TPD) of ammonia.The structure of the samples was characterized by XRD,and the textural properties of the catalysts were determined by nitrogen isothermal adsorption-desorption measurements and scanning electron microscopy(SEM).The XRD results show that the modified samples have no novel crystalline phase,indicating a high dispersion of phosphorus and boron species.After treatment,the microporous volume and surface area of the samples markedly decrease,implying the bolockage of the channel.The nitrogen adsorption-desorption measurements suggest that the isothermal type of all samples is a combination of isothermal type Ⅰ and Ⅳ，and all hysteresis loops resemble the H4-type in the IUPAC classification.The total acidity of the modified samples,determined by pyrldine adsorption IR and TPD of ammonia,decreases in contrast to that of the parent HZSM-5.The conversion of n-heptane over P and B steammodified HZSM-5 is higher than that of P and B-modified HZSM-5 zeolites but lower than that of the parent HZSM-5.