Rapid Detections Of Pesticide Residue In Nanfeng Citrus Fruits Using Surface-Enhanced Raman Spectroscopy

Fruits and vegetables are rich in nutrients, but recently pesticide residues in garden stuff are serious problems that cannot be ignored. As one of the main economic crops in southern China, There is a huge nutritional and commodity value in Nanfeng orange. The equipment was costly and time was consumed when we detected in pesticide residues traditional detection method. It is not conducive to the rapid detection of pesticide residues in tangerine. The surface-enhanced Raman spectroscopy?SERS? technique was widely used in all sides, as it's advantage of fast detection, high efficiency, high sensitivity and being able to carry-on. In this paper, we studied on rapid detection of three kinds of pesticide residues in Nanfeng oranges based on the SERS technology. The main research contents were as follows:?1? Qualitative and quantitative analysis of prochloraz pesticide residue in Nanfeng oranges based on the SERS technique. The study used nanoscale colloidal gold as SERS enhancement base and used acetonitrile as the dissolving agent. Then the stroma flowed through the mixed packing?anhydrous magnesium sulfate, C18, graphitized carbon and PSA?. So that we can remove the interference from pigment, ribose and other substances in Nanfeng Orange. Analyze the prochloraz standard solution through SERS spectrum peaks curve, five characteristic peaks of prochloraz are identified, namely 426,572, 698, 1078 and 1256cm^-1. The standard curve was plotted with the intensity of the peak1078cm^-1 and the SERS signals of prochloraz standard solutions?2²5mg/L?. There was a good linear relationship.The linear equation in flesh was y=21.979x+1834.7, the correlation coefficient R² was 0.95763. The rate of recovery in 3,10 and 20mg/L were82.7%¹09.6%, relative standard deviation RSD were 7.8%-9.0%. The linear equation in flesh was y=88.886.x+1642.1, the correlation coefficient R² was 0.92973. The rate of recovery in 3,10 and 20mg/L were 105.5%¹14.2%, relative standard deviation RSD were5.85%⁸.11%. Prochloraz solutions with orange extract as the matrix can be detected by SERS method in low concentrations of 2mg/L.?2? Qualitative and quantitative analysis of acetamiprid pesticide residue in Nanfeng oranges based on the SERS technique.The study used nanoscale colloidal gold as SERS enhancement base and used acetonitrile as the dissolving agent. Analyze the acetamiprid standard solution through SERS spectrum peaks curve, six characteristic peaks of acetamiprid were identified, namely542, 628, 830, 850, 1108 ? 1490cm^-1.The standard curve was plotted with the intensity of the peak at 1108cm^-1 and the SERS signals of acetamiprid standard solutions?5²5mg/L?. There was a good linear relationship.The linear equation was y=127.89x+1476.9, the correlation coefficient was R²=0.97257. The rate of recovery in 8, 12 and 25mg/L were 82.8%¹04.9%, relative standard deviation RSD were 1.5%⁵.6%. Acetamiprid solutions with orange extract as the matrix can be detected by SERS method in low concentrations of 5mg/L.?3? Qualitative and quantitative analysis of chlorpyrifos-methyl pesticide residue in Nanfeng oranges based on the SERS technique. Analyze the chlorpyrifos-methyl standard solution through SERS spectrum peaks curve, five characteristic peaks of chlorpyrifos-methyl were identified, namely 456, 520, 610, 675 and 1286cm^-1. The standard curve was plotted with the intensity of the peak at 675cm^-1 and the SERS signals of chlorpyrifos-methyl standard solutions?2⁴5mg/L?. There was a good linear relationship.The linear equation was y=65.827x+1526.5, the correlation coefficient was R²=0.98989.The rate of recovery in 3, 10 and 30mg/L were 80.2%¹09.2%, relative standard deviation RSD were 2.0%⁶.8%. Chlorpyrifos-methyl solutions with orange extract as the matrix can be detected by SERS method in low concentrations of 2mg/L.This study proved that we can give rapid qualitative quantitative analysis on prochloraz, acetamiprid and chlorpyrifos-methyl residues in Nanfeng orange based on surface enhanced Raman technology.