畜禽肉及饲料中氟苯尼考残留免疫分析方法研究

针对动物源性食品及饲料中氟苯尼考的残留问题,通过抗原制备、动物免疫和细胞融合筛选,成功得到可高特异性识别氟苯尼考的单克隆抗体,并建立了氟苯尼考的间接竞争酶联免疫分析(icELISA)方法.经单因素实验优化策略,确定最佳反应条件为:包被抗原质量浓度0.05μg/mL,抗体质量浓度为0.1μg/mL,最佳药物、抗体和二抗稀...     

液相色谱-串联质谱法测定鸡饲料中硝基咪唑类药物

提出了鸡饲料中5种硝基咪唑类药物(甲硝唑、洛硝哒唑、二甲硝唑、替硝唑和奥硝唑)的液相色谱-串联质谱分析方法。鸡饲料样品经乙酸乙酯-5g.L-1碳酸钠混合溶液提取后,取有机相蒸发至干。用0.1mol·L-1磷酸溶液溶解残余物,HLB柱固相萃取净化,所得的乙腈洗脱液经C8色谱柱为分离柱,甲醇和水混合溶液为流动相作梯度淋洗,采用正离子模式多反应监测。5种硝基咪唑类药物的线性范围均为10～500μg.L-1,检出限(3S/N)均为10μg.kg-1。加标回收率为79.4%～91.3%,批内相对标准偏差(n=6)为5.5%～13.9%,批间相对标准偏差(n=6)为6.7%～18.2%。     

Square-Wave Voltammetric Method for Determination of Aconitic Acid

ABSTRACT

A square-wave voltammetric method at a hanging mercury drop electrode for quantitative determination of aconitic acid in aqueous solution is developed. Aconitic acid is an electroactive compound in acid and neutral medium. Its voltammetric response depends on the type as well as the pH of the supporting electrolyte. The optimization of experimental parameters for quantitative determination of aconitic acid was achieved. The quantitative determination of aconitic acid was carried out in o. 1 mol/L HCl as a supporting electrolyte. The effect of interferences is studied. The detection limit of aconitic acid is 0.184 μg/mL.     

Voltammetric Behavior and Determination of Cinnarizine in Pharmaceutical Formulations and Serum

Abstract

The electrochemical reduction of cinnarizine was investigated by cyclic and linear sweep adsorptive voltammetry at glassy carbon electrode in Britton-Robinson buffers over the pH range 2.5–11.5. For analytical purposes, a well-defined adsorption-controlled cathodic peak was obtained at pH 2.5. By cathodic adsorptive linear sweep voltammetry, a linear calibration plot was obtained in the range of 2.0 × 10^?7 to 5.0 × 10^?6 mol L^?1 with detection limit of 9.0 × 10^?9 mol L^?1. The method was successfully applied to the determination of cinnarizine in commercial formulations with mean recovery and relative standard deviation of 100.24% and 1.46, respectively. The proposed method was also applied for drug determination in spiked serum samples by applying the standard addition method with a mean recovery of 97.80% and standard deviation of 3.06.     

Simultaneous Determination of Antimony and Lead in Gunshot Residue by Cathodic Adsorptive Stripping Voltammetric Methods

Differential pulse cathodic adsorptive stripping (DPCAdSV) and square wave cathodic adsorptive stripping (SWCAdSV) voltammetric methods were developed for the determination of antimony and lead in gunshot residues. Linear working ranges for DPCAdSV and SWCAdSV methods were (2.0×10^?9–5.0×10^?7) M and (2.0×10^?9–7.0×10^?7) M for antimony and 2.0×10^?9–3.0×10^?7 M (both methods) for lead. The detection of antimony limits were found to be 1.3×10^?9 M for DPCAdSV and 7.3×10^?10 M for SWCAdSV while the corresponding values for lead were 3.0×10^?9 M and 5.8×10^?10 M. Antimony and lead contents obtained by these methods in gunshot residues are in good agreement with those obtained by graphite furnace atomic absorption spectrometric method within a confidence limit of 95%.     

头孢噻肟钠的极谱伏安行为及其单扫描示波极谱法测定

以多种电化学手段研究了头孢噻肟钠的极谱伏安行为，在磷酸盐缓冲溶液中，头孢噻肟钠产生了一个不可逆吸附不原波，其峰电位为－０．７７Ｖ（ｖｓ．ＳＣＥ）。有二个电子和一个质子参与了电极反应。电极反应速率常数Ｋｓ为９．０×１０＾－６ｃｍ．ｓ＾－１。     

鳗鱼、饲料中恩诺沙星残留的测定及真假阳性辨别

采用反相高效液相色谱法(RP-HPLC),测定鳗鱼、饲料中的恩诺沙星药物残留．在Waters Nova-Pak C18柱上,用荧光检测器,激发波长280nm;发射波长450nm．流动相为5mmol／L NaH2PO4溶液-乙腈溶液(体积比为70：30),磷酸调pH值为2．7,流速1．2mL／min,柱温40℃．在鳗鱼、饲料中的最低检测限分别达到1μg／kg和2μg／kg,标准曲线在30—500ng／mL线性范围内相关系数达0．9997．在3种浓度水平对鳗鱼组织和饲料中的3种浓度进行回收率测定,其回收率在76％～98％之间;变异系数RSD小于8％,符合痕量测定要求．还对如何辨别真假阳性进行特别介绍．     

三元络合物微分阳极溶出伏安法测定亚硝酸根

基于NOi_2~-可以与Pb~(2+)和SCN~-形成稳定的三元络合物,NO_2~-的存在会抑制Pb~(2+)的还原富集,使铅的微分溶出峰电流i_p~′减小,根据其减小值△i_p~′,可以间接测定NO_2~-。工作电极为玻碳电极,预电解电位为—0.75V(vs. SCE),铅的溶出峰电位为—0.5V(vs. SCE)。本文对测定条件,干扰及其消除方法进行了研究。测定下限为2×10~(-11) mol/L,大量硝酸根不干扰。     

喜树碱的电还原特性及应用研究

The voltammetric behavior of camptothecin （CPT） in Britton-Robinson （B-R） buffer solutions （pH 2.09-9.07） was studied by the means of linear sweep voltammetry （LSV）, cyclic voltarnmetry （CV） and normal pulse voltammetry （NPV） at a hanging mercury drop electrode. In different pH range of B-R buffer solutions, CPT could cause three reduction waves. In B-R buffer solutions （pH 2.09-5.46）, wave P1 yielded by CPT was a two-electron wave. Between pH 6.01 and 9.07, CPT could yield two reduction waves P2 and P3. In addition, the pure CPT obtained from camptotheca acumina grown only in China was determined by NPV, and a linear response was observed in the range of 2.0 × 10^-3-4.0 × 10^-2 mmol·L^-1 with a 0.9991 correlation coefficient and a 8.0 × 1^-4 mmol·L^-1 detection limit for CPT.     

芦丁在玻碳电极上的阳极伏安行为及其测定

本文应用线性扫描伏安法，微分脉冲伏安和循环伏安法对芦丁在玻碳电极上的阳极伏安行为进行了研究。     

液相色谱-串联质谱法测定饲料中三聚氰胺残留

应用液相色谱-串联质谱法测定饲料中三聚氰胺残留。试样用V(乙腈)∶V(H2O)=1∶1溶液,提取,高速离心后,供液相色谱-串联质谱仪定性定量分析。流动相为V(乙腈)∶V(H2O)=80∶20混合溶液。采用电喷雾离子源,定性离子对为127.2/85.2和127.2/68.2;定量离子对为127.2/85.2。在添加了0.5~10.0 mg/kg的三聚氰胺标准品时的回收率为92.6%~103.2%;相对标准偏差(RSD)在0.8%~2.0%;检出限为0.2 mg/kg。     

Anodic Voltammetric Behavior and Determination of Antihistaminic Agent: Fexofenadine HCl

Abstract

A voltammetric study of the oxidation of fexofenadine HCl (FEXO) has been carried out at the glassy carbon electrode. The electrochemical oxidation of FEXO was investigated by cyclic, linear sweep, differential pulse (DPV), and square wave (SWV) voltammetry using glassy carbon electrode. The oxidation of FEXO was irreversible and exhibited diffusion‐controlled process depending on pH. The dependence of intensities of currents and potentials on pH, concentration, scan rate, nature of the buffer was investigated. Different parameters were tested to optimize the conditions for the determination of FEXO. For analytical purposes, a very well resolved diffusion‐controlled voltammetric peak was obtained in Britton‐Robinson buffer at pH 7.0 with 20% constant amount of methanol for DPV and SWV techniques. The linear response was obtained in supporting electrolyte in the ranges of 1.0×10^?6–2.0×10^?4 M with a detection limit of 6.6×10^?9 M and 5.76×10^?8 M and in serum samples in the ranges of 2.0×10^?6–1.0×10^?4 M with a detection limit of 8.08×10^?8 M and 4.97×10^?8 M for differential pulse and square wave voltammetric techniques, respectively. Only square wave voltammetric technique can be applied to the urine samples, and the linearity was obtained in the ranges of 2.0×10^?6–1.0×10^?4 M with a detection limit of 2.00×10^?7 M. Based on this study, simple, rapid, selective and sensitive two voltammetric methods were developed for the determination of FEXO in dosage forms and biological fluids. For the precision and accuracy of the developed methods, recovery studies were used. The standard addition method was used for the recovery studies. No electroactive interferences were found in biological fluids from the endogenous substances and additives present in tablets.     

Studies on the Voltammetric Behavior of Nicardipine Hydrochloride and its Voltammetric Determination at the Co/GC Modified Electrode

ＩｎｔｒｏｄｕｃｔｉｏｎＴｈｅｔｅｃｈｎｉｑｕｅｏｆｉｏｎｉｍｐｌａｎｔａｔｉｏｎｈａｓｂｅｅｎｄｅｖｅｌｏｐｅｄａｓａｍｅａｎｓｏｆｉｎｔｒｏｄｕｃｔｉｎｇｆｏｒｅｉｇｎａｔｏｍｓｉｎｔｏｔｈｅｓｕｒｆａｃｅｌａｙｅｒｓｏｆａｓｏｌｉｄ．Ｔｈｉｓｔ...     

分散固相萃取/高效液相色谱法测定水产品中氯苯胍的残留量

建立了水产品中氯苯胍残留的分散固相萃取/高效液相色谱检测法.采用酸化乙酸乙酯为提取溶剂、C18填料为基质分散剂提取水产品中残留的氯苯胍,经中性氧化铝柱净化,浓缩后用乙腈水溶液定容,经正己烷脱脂后上机检测,外标法定量.优化的色谱条件为:采用Agilent ODS-C18色谱柱(250 mm×4.6 mm,5μm)分离,以...     

Studies on the Voltammetric Behavior of Nicardipine Hydrochloride,its Voltammetric Determination at the Co/GC Modified Electrode

To whom correspondence should be addressed. In a 0.02 mol/L BR buffer solution(pH=5.52), the electrochemical behaviour of nicardipine hydrochloride was studied by linearsweep voltammetry, cyclic voltammetry at a Co/GC ion implantation modified electrode. The experiments showed that the electrode had a good stability, reproductivity. The peak height was proportional to the concentration of nicardipine over the range of 4.0×10^-7—1.0×10^-4 mol/L, the detection limit was 1.0×10^-7 mol/L. This method has been used for the direct determination of nicardipine in tablets. Its recoveries were in the range from 95.6% to 103.8%. The reduction of nicardipine at the Co/GC electrode was an irreversible proccess.     

Determination of Caffeic Acid in Red Wine by Voltammetric Method

The electrochemical oxidation of 3,4‐dihydroxycinnamic acid, caffeic acid, leads to a stable electroactive poly(caffeic acid) thin film containing quinone moiety on a preactivated glassy polymeric carbon electrode. The properties of the deposited films as well as the stability study under different experimental conditions were investigated. Taking advantage of the electrochemical behavior, an analytical method based on differential pulse voltammetry for determination of caffeic acid in red wine was proposed.     

碳糊电极吸附溶出伏安法测定游离钙

基于Ca(Ⅱ)-茜素红S(ARS)络合物在碳糊电极上的还原波,建立了吸附溶出伏安测定游离钙的新方法。在1.5×10-2mol/LKOH-2.0×10-5mol/LARS介质中,Ca(Ⅱ)-ARS络合物在碳糊电极上于-0.89V处产生一吸附还原波。当富集电位为.0.1V,富集时间90s,扫描速度为100mV/s时,该络合物单扫描阴极溶出峰的二阶导数峰电流与游离钙离子浓度在3.0×10-8~2.0×10-6mol/L范围内呈线性关系;检出限为9.4×10-9mol/L。在0.2mol/LHCl中清洗2min,该电极重现性良好。该方法可用于血清、牛奶和自来水中游离钙的测定。     

A Monoclonal Antibody-Based Indirect Competitive Enzyme-Linked Immunosorbent Assay for the Determination of Olaquindox in Animal Feed

A reliable indirect competitive enzyme-linked immunosorbent assay (ELISA) based on a new specific monoclonal antibody was developed to determine olaquindox in animal feed. The influence of several physicochemical factors (nonfat dried milk solution, organic solvent, incubation time) on the immunoassay was investigated. In the optimized system, the 50% inhibition concentration was 9.66 ± 1.81 µ g L^?1. The limits of detection for porcine, chicken, and fish feed were 0.28, 0.46, and 0.48 µg kg^?1. The limits of quantification were 1.00 µg kg^?1 for the feed samples. The recoveries from porcine, chicken, and fish feed spiked with olaquindox were 90–104%, 77–103%, and 78–107%, respectively, with coefficients of variation (CVs) between 3.8 and 14.1%. The cross-reactivity was less than 2.08% with four structurally related compounds and no recognition of five other restricted or forbidden drugs was observed. Parallel analysis of the three spiked feed samples showed comparable results between the indirect competitive ELISA and the standard high-performance liquid chromatography method in China (R² = 0.9985 for porcine feed, R² = 0.9896 for chicken feed, and R² = 0.9987 for fish feed). These data suggest that the developed indirect competitive ELISA is a specific and convenient method and is suitable for olaquindox determination in animal feed.     

Voltammetric Behavior of Strychnine, and its Determination in Strychno Nux-Vomica Seeds Extract

The voltammetric behavior of strychnine has been studied with a pyrolytic graphite (PG) electrode. The redox process taking place at the PG electrode is discussed. The cyclic voltammetric response has also been evaluated with respect to various experimental conditions, such as scan rate, pH of the supporting electrolyte, strychnine concentrations and accumulation time. A highly sensitive voltammetric method for the determination of strychnine is consequently developed. The linear calibration is in the range of 1×10⁻⁶ M – 1.1×10⁻⁴ M, with the limit of detection (LOD) being 1×10⁻⁸ M. The precision is excellent with a relative standard deviation (RSD) of 2.3%. The proposed cyclic voltammetric methodology has been applied to the determination of strychnine in the extract of Strychno nux-vomica seeds using the standard addition method. Consistent results have been obtained from both the electrochemical approach described here and the previously reported HPLC method.     

液相色谱串联质谱法同时测定饲料中8种苯并咪唑类药物

建立了同时测定饲料中8种苯并咪唑类药物(噻苯咪唑、丙硫咪唑、硫苯咪唑、苯硫氧咪唑、氟苯咪唑、甲苯咪唑、丙氧苯唑和三氯苯唑)的液相色谱串联质谱分析方法。饲料样品用酸化乙腈直接提取,提取液用甲酸溶液稀释后进行分析。分析时用XBridgeTMC18色谱柱,以甲酸溶液-乙腈体系进行梯度洗脱,MRM方式测定,基质外标法定量。8种苯并咪唑类药物均在0.02~10.0 mg.L-1范围内呈良好的线性关系,相关系数(r2)均不低于0.990,在饲料样品中的检出限为2.1~63.0μg.kg-1。饲料中苯并咪唑类药物在0.50、30、200 mg.kg-13种加标水平下的回收率为84%~104%,相对标准偏差均小于10.0%。方法分析单个样品约需30 min,该方法适合饲料中8种苯并咪唑类药物的同时分析。