统计模拟分光光度法测定复方消咳新片组分含量

用统计模拟分光光度法测定复方消咳新片４个组分含量。按均匀设计表制备合成样品，绘制溶液的ＵＶ－ＶＩＳ吸收曲线，获得有限但足够的实验数据，用逐步回归法构造反映该复方制剂组分在灵敏波长的吸光度－组分含量经验关系的“最优”数学模型，用改进单纯形法寻优，求出未知样品的各组分含量。磺胺甲基异恶唑、甲氧苄胺嘧啶、盐酸溴已新、枸橼酸维静宁的回收率分别为１００３％、１００４％、９９９％、９９０％，标准差分别为０９１％、１４％、１２％、３９％。     

Development and critical comparison of greener flow procedures for nitrite determination in natural waters

Two greener procedures for flow-injection spectrophotometric determination of nitrite in natural waters were developed and critically compared. Replacement of toxic reagents, waste minimization and treatment were exploited to attend the standards of clean chemistry. The flow system was designed with solenoid micro-pumps in order to minimize reagent consumption and waste generation. The first procedure is based on the Griess diazo-coupling reaction with sulfanilamide and N-(1-naphthyl)ethylenediamine (NED) yielding an azo dye, followed by photodegradation of the low amount of waste generated based on the photo-Fenton reaction. The second procedure is based on the formation of iodine from nitrite and iodide in acid medium in order to avoid the use of toxic reagents. For Griess method, linear response was achieved up to 1.0 mg L^− 1, described by the equation A = − 0.007 + 0.460C (mg L^− 1), r = 0.999. The detection limit was estimated as 8 μg L^− 1 at the 99.7% confidence level and the coefficient of variation was 0.8% (n = 20). The sampling rate was estimated as 108 determinations per hour. The consumption of the most toxic reagent (NED) is reduced 55-fold and 20-fold in comparison to batch method and flow injection with continuous reagent addition, respectively. A colorless residue was obtained by in-line photodegradation with reduction of 87% of the total organic carbon content. The results obtained for natural water samples were in agreement with those achieved by the reference method at the 95% confidence level. For the nitrite–iodide method, linear response was observed up to 2.0 mg L^− 1, described by the equation A = − 0.024 + 0.148C (mg L^− 1), r = 0.999. The detection limit was estimated as 25 μg L^− 1 at the 99.7% confidence level and the coefficient of variation was 0.6% (n = 20). The sampling rate was estimated as 44 determinations per hour. Despite avoiding the use of toxic reagents, the nitrite–iodide method presented worst performance in terms of selectivity and sensitivity.     

双波长分光光度法同时测定岩石矿物中的微量金和钯

本文提出以硫代米蚩酮为显色剂，用双波长分光光度法同时测定岩石矿物中的微量金和钯的方法，消除了测定金钯的相互干扰，该方法简便，快速，选择性好，用于矿石样品中金和钯的测定，结果满意。     

动力学分光光度法测定痕量硫氰酸根的研究

利用SCN~-对溴酸钾氧化罗丹明B反应的抑制作用。建立了动力学光度法测定痕量SCN~-的新方法。检出限为0.30ng SCN~-/ml,测定范围为0.30～8.3ngSCN~-/ml.应用于吸烟者与不吸烟者尿中SCN~-的测定。结果较为满意。     

偏最小二乘法分光光度同时测定复方扑热息痛片中各组分含量

本文介绍了偏最小二乘法(PLS)用于多组分分光光度分析的基本原理和算法.研究了复方扑热患痛片中扑热息痛、阿司匹林和咖啡因的PLS测定方法,各组分的平均回收率分别为99.88±0.33％、99.99±0.14％和99.92±1.24％(置信度95％).     

A Highly Sensitive Spectrophotometric Assay of Bleomycins Based on the Fading Reaction of Some Halofluorescein Dyes

In weak acidic medium, anticancer antibiotics bleomycin A5 （BLMA5） and bleomycin A2 （BLMA2） can react with halofluorescein dyes such as erythrosin （Ery）, eosin Y （EY）, eosin B （EB） and rose bengal （RB） by virtue of electrostatic attraction and hydrophobic force to form the ion-association complexes, which can result in the fading reactions of four halofluorescein dyes. The maximum fading wavelengths of these four dyes were located at 527 nm for Ery, 515 nm for EY, 517 nm for EB and 546 nm for RB, respectively. The decrements of absorbance （AA） were directly proportional to the concentrations of bleomycin in a certain range. A new method for the determination of bleomycins anticancer drugs based on fading reactions of halofluorescein dyes has been developed. The method was not only highly sensitive but also simple and rapid. The molar absorptivities （ε） ranged from 1.5 × 10^5 to 7.5 × 10^5 L·mol^-1·cm^-1. It was applied to determination of the bleomycins in human serum, urine and rabbit serum samples. In this work, the spectral properties and the optimum reaction conditions were investigated. The structure of ion-association complexes and the reaction mechanism were discussed.     

铬（Ⅲ）邻菲咯啉,8—羟基喹啉配合物／Y型分子筛的制备及苯酚催化羟化

制备了铬（Ⅲ）邻菲咯啉，８－羟基喹啉配合物／Ｙ型分子筛，利用元素分析，ＳＥＭ，ＵＶ－ＶｉｓＢＥＴ及ＸＲＤ等方法确定了分子筛选笼中金属配合物的生在及其晶体结构，考察了实验参数对苯酚转化率及产物选择性的影响。     

萃取动力学光度法测定活化剂铝——铝(Ⅲ)-过氧化氢-铜(Ⅱ)-邻氨基酚/氯仿体系

研究了在pH 5.5的弱酸性介质中, 利用Al(Ⅲ)对Cu(Ⅱ)催化H2O2氧化邻氨基酚显色的指示反应的活化作用.用萃取平衡控制反应时间、水相中邻氨基酚的浓度和反应进行的程度.通过在424 nm下测量有机相的吸光度,建立了萃取催化光度法测定活化剂铝的新方法.方法的线性范围为0.004～0.25 mg/L,检出限为1.6×10 -6 g/L.用于水样和茶叶中铝含量的测定,结果满意.     

增敏双波长光度法同时测定底泥中的铜和铬

在pH6．4的磷酸二氢钾-磷酸氢二钾缓冲液和CIMAJB、正丁醇、正庚烷组成的微乳液的介质中，水杨基荧光酮与铜（Ⅱ）、铬（Ⅵ）的显色体系灵敏度都有很大提高，选择了合适的测定波长，利用双波长解方程组法同时测定了底泥中的铜和铬。结果令人满意。     

Flow and Sequential Injection Manifolds for the Spectrophotometric Determination of Captopril Based on its Oxidation by Fe(III)

 Two new simple and rapid methods are reported for the accurate and precise spectrophotometric determination of captopril (CPL) using flow (FI) and sequential injection (SI) analysis. The methods are based on the fast oxidation of CPL by Fe(III). The produced Fe(II) reacts with 2,2′-dipyridyl-2-pyridylhydrazone (DPPH) in acidic medium to form a colored complex which is monitored spectrophotometrically at 535 nm. Both methods allow the determination of the analyte up to 1000 mg L⁻¹ at a sampling rate of 120 and 60 injections per hour for FI and SI, respectively. The methods are very precise [s _r=0.8 and 1.2% at 500 mg L⁻¹ CPL (n=12) for FI and SI, respectively] and the 3σ detection limits (c _L=4.0 and 7.0 mg L¹, respectively) are quite satisfactory. Their application to a variety of anti-hypertensive commercial pharmaceutical formulations showed excellent results (relative errors, e _r, < ± 1.6% in all cases compared to an official HPLC method), while common pharmaceutical excipients were found not to interfere. Recovery experiments further verified the accuracy of the developed methods, as the percent recoveries were in the range of 98.1–102.5%. Author for correspondence. E-mail: themelis@chem.auth.gr Received May 9, 2002; accepted January 8, 2003 Published online May 5, 2003