摘要
合成了新荧光试剂2-(5′-磺基-2′-苯酚-1′-偶氮)-5-乙氨基-4-甲酚(SPAEC)。用等色点光度法测得试剂的离解常数为pK_1=3.42,pK_2=5.46,pK_3=7.99。考察了SPAEC与金属离子的螯合显色和荧光反应;建立了测定镓、铝的反应条件,在pH3.8—5.4或pH4.0—5.5的乙酸缓冲介质中均形成1∶1型具荧光活性的有色螯合物,可相应测定15—150ppb镓及1.5—30ppb铝,试用于半导体及合金分析。研究了Kalman滤波荧光光度法,实现了镓与铝的同时测定,所适应的浓度比例范围为40∶1(0)—1(0)∶14。
A now fluorescent reagent, 2-(5'-sulfo-2'-hydroxy phenyl-1'-azo)-5-ethylamino-4-cresol (SPAEG), has been synthesized. The acidic dissociation constants were estimated by the iscbestic point method, pK_1=3.42, pE_2=5.46, pK_3=7.99. SPAEC forms color and/or fluorescent chelates with Al^(3+), Ga^(3+), In^(3+), So^(3+), Fe^(3+), Cu^(2+), Zr^(4+), Hf^(4+) and some of rare earth ions. The optimal conditions for fluorescent chelating formation between SPA EG and Ga^(3+) or Al^(3+) ion have been established. At pH3.8 to 5.4, with λ_(ex) and λ_(em) of 515 and 585 nm respectively, quantum yield was 0.046 for Ga_(3+). For Al_(3+), at pH 4.0 to 5.5 and the λ_(ex) and λ_(em) of 535(or 520) and 575 nm, respectively, quantum yield was 0.104. The SPAEC chelates were 1:1 type for both Ga^(3+) and Al^(3+). The proposed method can be used for determination of 15—150 ppb Ga and 1.5—30 ppb Al in alloy and semiconductor samples with satisfactory results. Finally, a method for simultaneous determination of Al and Ga using SPAEC has boon developed by the use of fluorometry combined with Kalman filter. This combination can considerably improve the selectivity of a highly sensitive fluorometric method showing a good prospect for trace analysis.
出处
《化学学报》
SCIE
CAS
CSCD
北大核心
1990年第10期1018-1023,共6页
Acta Chimica Sinica
基金
国家教委高校基金
国家自然科学基金
