Determination of Paraquat in Water, Rice, and Urine Samples by Resonance Light Scattering Technique with DNA

Abstract

In this paper, a rapid and accurate method was developed for the determination of paraquat by a resonance light scattering (RLS) quenching technique with a common spectrofluorometer. In the presence of paraquat, the intensity of resonance light scattering (I RLS ) of DNA-HCL system was significantly quenched. A resonance light scattering peak at 308 nm was found. At this wavelength, the decrease in I RLS was in proportion to the concentration of paraquat. The linear range of the calibration curve was approximately 0.05-1.0 lg mL À1 and the detection limit (S/N ¼ 3) was 0.036 lg mL À1 . The recovery rates of paraquat in river water, rice, and urine samples were determined with satisfactory results. The solid-phase extraction was used for the preparation of urine sample. The spectral characteristics of the ctDNA-paraquat-HCl system were also discussed. INTRODUTIONResonance light scattering (RLS) phenomenon, as an analytical technique has become the focus of many recent studies for its high sensitivity, simplicity, and rapidity. In 1993, Pasternack found that the enhance RLS signals in an aggregation medium could even be detected by using a common spectrofluorometer and established a method which could characterize the spectral characteristics of molecular aggregation (Pasternack et al. 1993). The RLS technique has proven to be a promising method not only for the study of aggregation and assembly of biological and chemical species, but also for the determination of nucleic acids, proteins, inorganic ions, surfactants, and drugs (Chen et al. 2006).

Magnetic Solid-Phase Extraction Using Fe3O4@SiO2 Magnetic Nanoparticles Followed by UV-Vis Spectrometry for Determination of Paraquat in Plasma and Urine Samples

“…During the last few decades, a number of analytical methods have been reported for the identification and quantitation of paraquat in biological samples, which includes spectrophotometry [ 7 , 8 ], gas chromatography (GC) [ 9 ], gas chromatography-mass spectrometry (GC-MS) [ 10 , 11 ], high performance liquid chromatography (HPLC) [ 12 , 13 ], high performance liquid chromatography coupled with mass spectrometry (HPLC-MS) [ 14 ], resonance light scattering technique (RLST) [ 15 ], voltammetry [ 16 ], and derivative spectroscopy [ 17 ]. Most of these methods often require expensive devices and professional operators, are associated with high cost, and thus are limited in clinical use.…”

Paraquat and Diquat: Recent Updates on Their Pretreatment and Analysis Methods since 2010 in Biological Samples

“…de Almeida et al [ 87 ] developed an enzymatic-spectrophotometric method based on the velocity of NADPH consumption for the detection of PQ and obtained an LOD of PQ of 0.05 μg/mL in urine samples. Li et al [ 88 ] developed a resonance light scattering (RLS) quenching technique with a spectrofluorometer to detect PQ in urine sample. The calibration curve was in the range of 0.05–1.0 μg/mL, and the LOD was 0.036 μg/mL for PQ.…”