摘要
提出用已二酰二氯作交联剂,聚乙烯醇(PVA)涂层改性聚四氟乙烯(PTFE)膜质毛细管,并用于多酚氧化酶(PPO)的固定,在线分析过程采用流动注射系统。这种经修饰的PTFE膜质毛细管可催化水溶液中酚的氧化,氧化产物与染料4-氨基安替比林偶合生成的有色化合物再经未涂层的PTFE膜质毛细管循环15 min分离富集,用乙醇洗脱后进入流通池在510 nm波长处进行在线检测。对在线酶催化反应和显色反应的时间,试验进入反应圈1及2时的流速,淋洗时,淋洗液的流速等均给了最佳参数。反应系在pH 6.8的磷酸盐缓冲介质中进行。该方法的线性范围为0.5～60μg·L^(-1),水样中常见的离子和化合物不干扰酚的测定。应用此法分析了地下水及自来水样中痕量酚,所得结果与国标标准方法所得结果之间的相对误差在1.8%～3.3%范围内。
Polyphenol oxidase （PPO） was immobilized on the surface of PTFE membranous capillary by using adipoyldichloride as crosslinking agent. A FI-manifold was used for the on-line analytical process. Phenols in water sample were enzymatically oxidized when cycling in the PVA-PPO modified PTFE membranous capillary, and the oxidation products of phenols were reacted with 4-aminoantipyrine to give a colored compound. The colored solution of definite volume was enriched by cycling for 15 min in the un-modified PTFE membranous capillary, the colored compound was eluted from the unmodified capillary with ethanol, and the absorbance of the eluate was measured at the wavelength of 510 nm. Optimum parameters of time for on-line enzymatic oxidation, time for on-line color reaction, flow-rate of introduction of sample solution in reaction cycle 1 and 2, and flow-rate of the eluant during elution, were given and the reaction was carried out in PBS of pH 6. 8. Range of linearity found was between 0. 5-- 60μg·L^-1. Common co-existing ions and compounds were found to be non-interfering. The proposed method was used in the analysis of samples of ground water and tap water, the results were checked by the international standard method, giving relative errors ranged from 1.8% to 3. 3%.
出处
《理化检验（化学分册）》
CAS
CSCD
北大核心
2009年第8期889-892,897,共5页
Physical Testing and Chemical Analysis(Part B:Chemical Analysis)
