Ultra Stable Dual Functionalized Gold Nanoparticles for the Effective Colorimetric Detection of Clenbuterol

Abstract

Clenbuterol, a medium cumulative drug also appears as residues in animal would cause dizziness, fatigue, arrhythmia, and metabolic disorders in humans if eaten.1 Illegal abuse of clenbuterol was not stopped eventhough it has been banned from adding to animal feeds in many countries.2 Clenbuterol incident at Shanghai Co. (March 2011) caused great concern worldwide.3 Therefore, recently many sensor probes have been developed for the detection of clenbuterol. Among them, gold nanoparticles based detection was found to be promising.4, 5 However, to the best of our knowledge, dual functionalized AuNPs have not been reported for the detection of clenbuterol. Henceforth, we tend to develop ultra stable dual functionalized AuNPs for the effective detection of Clenbuterol (CLB). These newly ultra stable dual functionalized PE-Glu-AuNPs were developed by functionalization of AuNPs with Glutamic acid (Glu) and poly ethyleneimine (PE)via NaBH4 reduction method. We have elucidated the stability of PE-Glu-AuNPs over a period of six months. Further, the colorimetric assay of PE-Glu-AuNPs to CLB revealed that, its selective sensing ability starts from 300 nM visualized through naked eyes at pH 5. Additionally, the sub nanomolar detection of CLB has been estimated from linear fittings and standard deviation of UV-vis titration. The reaction mechanism was further verified through TEM images and dynamic light scattering (DLS) data. By DLS analysis, the initial size of PE-Glu-AuNPs was calculated to be 12.8 ± 8.6 nm, which later aggregated as 84.8 ± 52.3 nm during the detection of CLB-(C). It has also been well demonstrated that the probe does not evidence the selectivity towards any other interferences (A-Alamine; B-Phenylalanine; D-Nacl; E-CaCl2; F-Threonine; G-Cysteine; H-Glycine; I-Glucose and J-Urea). Moreover, the aggregation induced detection of CLB was well confirmed by TEM studies. References Brambilla, G.; Cenci, T.; Franconi, F.; Galarini, R.; Macrì, A.; Rondoni, F.; Strozzi, M.; Loizzo, A. Toxicol. Lett. 2000, 114, 47−53.Wu, K. S.; Guo, L.; Xua, W.; Xu, H. Y.; Aguilar, Z. P.; Xu, G. M.; Lai, W. H.; Xiong, H.; Wan, Y. Q. Talanta 2014, 129, 431−437. Yan, H.; Xu, D.; Meng, H.; Shi, L.; Li, L. Qual. Assur. Saf. Crops Foods 2015, 7, 27−35. Zhang, X. F.; Zhao, H.; Xue, Y.; Wu, Zh. J.; Zhang, Y.; He, Y. J.; Li, X. J.; Yuan, Zh. B. Biosens. Bioelectron. 2012, 34, 112−117. Kang, J.; Zhang, Y.; Li, X.; Miao, L.; Wu, A. ACS Appl. Mater. Interfaces 2016, 8, 1−5 Figure 1