基于Eu^(3+)-生物质碳量子点探针的比率型荧光传感体系检测盐酸四环素

A Ratiometric Fluorescence Sensing System Based on Eu^(3+)-Bio⁃mass Carbon Dot Probe for the Detection of Tetracycline Hydrochloride

该文以橙皮为原料制备的碳量子点(CDs)与铕离子(Eu^(3+))构建双发射比率型荧光探针(Eu^(3+)-CDs)并用于抗生素盐酸四环素的检测。在370 nm激发波长下,Eu^(3+)-CDs荧光探针在425 nm处出现较强的蓝色荧光峰,在617 nm处出现较弱的红色荧光峰。随着盐酸四环素浓度的逐渐增大,Eu3+与盐酸四环素螯合形成的配合物增多,在425 nm处的CDs荧光(I_(F425))逐渐减弱,而617 nm处铕配合物的荧光(I_(F617))逐渐增强,可基于荧光强度比I_(F617)/I_(F425)的变化对盐酸四环素进行测定。考察了Eu^(3+)的浓度、pH值和反应时间对探针荧光强度的影响。在最佳条件下,该双发射比率型荧光探针对盐酸四环素具有特异性识别能力,荧光强度比(I_(F617)/I_(F425))与盐酸四环素浓度在10~100µmol/L范围内存在良好的线性关系,相关系数r^(2)=0.9926,检出限为5.09µmol/L。该方法成功用于猪肉中盐酸四环素含量的检测,加标回收率为102%~110%,相对标准偏差为0.20%~2.4%,具有较好的实用性。

Carbon quantum dots(CDs)prepared from orange peel were employed to construct a dualemission ratiometric fluorescent probe(Eu^(3+)-CDs)with europium ions(Eu^(3+))for the detection of the antibiotic tetracycline hydrochloride.The Eu^(3+)-CDs fluorescent probe exhibits two distinct fluores⁃cence peaks at 370 nm excitation:a robust blue peak at 425 nm and a comparatively moderate red peak at 617 nm.With the concentration of tetracycline hydrochloride increased,Eu3+chelated with tetracycline hydrochloride to form more complexes.As a result,the fluorescence of CDs at 425 nm(I_(F425))steadily dropped while that of europium complexes at 617 nm(I_(F617))increased.This variation in fluorescence intensity ratio of I_(F617)/I_(F425) allowed for the measurement of the tetracycline hydrochloride content.The effects of Eu3+concentration,pH value and reaction time on the fluorescence intensity were investigated.Under the optimal conditions,the dual-emission ratiometric fluorescent probe had a specific recognition ability for tetracycline hydrochloride.A good linear relationship between the flu⁃orescence intensity ratio(I_(F617)/I_(F425))and the concentration of tetracycline hydrochloride(10-100µmol/L)was obtained.The linear equation was I_(F617)/I_(F425)=0.01561c(µmol/L)+0.05081,and the linear correlation coefficient was r^(2)=0.9926 with the detection limit of 5.09µmol/L.The method was suc⁃cessfully utilized to detect the content of tetracycline hydrochloride in pork with the spiked recoveries of 102%to 110%and the relative standard deviations of 0.20%-2.4%.