溴化十六烷基吡啶的双波长共振光散射比率法测定  

Determination of Cetylpyridinium Bromide by Dual Wavelength Resonance Light Scattering Ratiometry

作　　者：蒋婷[1] 张国文[1] 王安萍[1] 潘军辉[1] 

机构地区：[1]南昌大学食品科学与技术国家重点实验室,江西南昌330047

出　　处：《分析测试学报》2008年第9期984-987,共4页Journal of Instrumental Analysis

基　　金：江西省自然科学基金资助项目(2007GZH1924);江西省教育厅科技计划资助项目(GJJ08025);教育部长江学者与创新团队发展计划资助项目(IRT0540)

摘　　要：应用双波长共振光散射（DW—RLS）比率法研究了溴百里酚蓝（BTB）与阳离子表面活性剂溴化十六烷基吡啶（CPB）的相互作用。在pH1．5的乙酸钠-HCl缓冲溶液中，CPB本身的共振光散射很弱，BTB有一定的共振光强度，加入CPB后BTB的共振光信号显著增强，最大散射峰位于523nm，且散射光强度与CPB的浓度呈线性关系，可以通过单波长共振光散射法检测CPB，CPB质量浓度的线性范围和检出限分别为0．05—0．60mg／L和42μg／L。使用248nm和424nm两波长处散射强度比值（I248／I424）代替单波长处的共振光散射强度测定CPB，其线性范围和检出限分别为0．03～1．0mg／L和3μg／L。与共振光散射法相比较，DW—RLS比率法受酸度、离子强度等环境条件影响较小，并且有更宽的线性范围和更低的检出限，应用于合成和实际水样中CPB的测定，获得较好的结果。A dual-wavelength resonance light scattering（DW-RLS） ratiometric method based on the interaction between bromothymol blue（BTB） and cetylpyridinium bromide （CPB） was developed for the determination of CPB. In NaAc - HCl buffer solution （ pH 1.5 ）, the RLS signals of CPB and BTB were relatively weak, but the RLS signal of BTB was enhanced significantly by CPB showing a characteristic peak at 523 nm. Two other RLS peaks at 248 nm and 296 nm and a valley at 424 nm could also be observed using a ratio spectrum of absorbance, i.e. ABTB-CPB/ ABTB. The enhanced RLS signal increased with increasing CPB concentration. By measuring the RLS signals at 523 nm（ i. e. single wavelength SW-RLS）, a linear response of CPB over the range of 0. 05 - 0.60 mg/L with the limit of 42 μg/L could be obtained, while by measuring the RLS peak to valley intensity ratio （I248/ I424 ） at dual wavelengths （ DW-RLS ratiometry）, a linear response of CPB over the range of 0. 03 - 1.0 mg/L with the limit of 3 μg/L was obtained. It was obvious that the DW-RLS ratiometry was better than SW-RLS in terms of linear response range and detection limit. Experimental results also demonstrated that DW-RLS ratiometry was less affected by the environmental conditions including pH and ionic strength. The proposed method was applied to the analysis of synthetic and real water samples with satisfactory results.

关 键 词：共振光散射 双波长比率 溴化十六烷基吡啶 

分 类 号：O657.3[理学—分析化学]