Smartphone Based Microanalytical Device for Immunoassay of 2,4-D Determination

Abstract

Onsite rapid detection of herbicide and herbicide residuals in environmental and biological specimens is important for agriculture, environment, food safety, and health care.1-2 Traditional method for herbicide detection requires expensive laboratory equipment and a long turn-round time.3-5 In this work, we developed a single-stripe microtiter plate smartphone colorimetric device for rapid and low-cost in-field test (Figure). This portable smartphone platform is capable of screening 8 samples in a microplate single-stripe. The device was validated with good sensitivity. Reliable linear relationship for detection were obtained comparing with microplate reader. This optosensing device were put into practical application for 2,4-D detection. Different concentration of 2,4-D from 80 ng/mL to 1 ng/mL were detected by the smartphone device, good linear relationship was obtained. The detection limit is down to 1 ng/mL which is lower than ELIASA reader. For real ground water sample and blood sample, it gives a good recovery rate and good linear relationship. It validated that the smartphone optical sensing platform is eligible for onsite rapid and low-cost detection of herbicide in practical samples for environmental evaluation and biological monitoring. Figure . (a) Three-dimensional structure of the smartphone based single stripe microplate reader. (b) Linear analysis of 2,4-D under the best experiment condition. References： McDuffie, H. H.; Pahwa, P.; McLaughlin, J. R.; Spinelli, J. J.; Fincham, S.; Dosman, J. A.; Robson, D.; Skinnider, L. F.; Choi, N. W. Cancer Epidemiol. Prev. Biomark. 2001, 10 (11), 1155–1163.Takashima-Uebelhoer, B. B.; Barber, L. G.; Zagarins, S. E.; Procter-Gray, E.; Gollenberg, A. L.; Moore, A. S.; Bertone-Johnson, E. R. Environ. Res. 2012, 112, 171–176.Hughes, D. L.; Ritter, D. J.; Wilson, R. D. J. Environ. Sci. Health Part B 2001, 36 (6), 755–764Jia, J.-L.; Xu, H.-H.; Zhang, G.-R.; Hu, Z.; Xu, B.-Q. Nanotechnology 2012, 23 (49), 495710.Wang, X.; Yu, J.; Wu, X.; Fu, J.; Kang, Q.; Shen, D.; Li, J.; Chen, L. Biosens. Bioelectron. 2016, 81, 438–444. Figure 1