【摘要】 采用聚乙烯亚胺作保护剂,利用THPC还原氯金酸制备金纳米粒子(AuNPs),该粒子溶液在375 nm激发下,在513 nm处有荧光发射。实验发现,Au NPs粒子于p H 7. 8的磷酸盐缓冲介质中加入没食子酸丙酯(PG),体系的激发波长变为333 nm,发射波长变为380 nm,荧光蓝移且强度明显增强,由此建立了一种快速检测PG的新方法。考察了缓冲体系pH、反应时间、反应温度、AuNPs溶液浓度对PG测定的影响。结果表明,检测PG的最佳条件为:缓冲体系pH 7. 8,反应时间20min,反应温度25℃,AuNPs原液稀释10倍。在最佳条件下,PG与金纳米体系荧光强度在0. 02～1. 06μg/m L范围内呈良好的线性关系,相关系数(R2)为0. 999 3,检出限为9. 7×10-3μg/m L。该方法用于食用油中PG的检测,加标回收率为92. 1%～104. 1%。更多还原

【Abstract】 The gold nanoparticles( Au NPs) were synthesized from chloroauric acid in aqueous solution with polyethyleneimine as protective agent and THPC as reductant. Au NPs showed a fluorescence emission at 513 nm under excitation of 375 nm. It was found that when the Au NPs were added with propyl gallate( PG) in a phosphate buffer medium with p H 7. 8,the excitation wavelength of the system became333 nm,and the intensity wavelength became 380 nm,which caused the gold nano-fluorescence blue shift and the intensity to be significantly enhanced. Thus a new method for determining PG rapidly was established. Different factors were studied,including the AuNPs concentration,buffer solution p H,reaction time and reaction temperature. The results showed that the optimal conditions for determining PG were obtained as follows: buffer solution p H 7. 8,reaction time 20 min,reaction temperature 25 ℃ and AuNPs solution diluted ten times. Under the optimal conditions,the PG mass concentration had a better linear relationship with the AuNPs fluorescence intensity in the range of 0. 02-1. 06 μg/m L. The correlation coefficient( R2) was 0. 999 3,and the detection limit was 9. 7 × 10-3μg/m L. The method was used to detect PG in edible oil,and its recovery rate of standard addition was 92. 1%-104. 1%.更多还原