Development of an Immunosensor for Determination of the Fungicide Chlorothalonil in Vegetables, Using Surface Plasmon Resonance

Abstract

An immunosensor based on surface plasmon resonance (SPR-sensor) was developed to analyze chlorothalonil residues and maximum residue limits (MRLs; 0.5-50 mg/kg) in vegetables in Japan. Conjugates of N-(pentachlorophenoxyacetyl)glycine and bovine serum albumin were covalently coated on the sensor chip. The SPR-sensor quantitatively determined chlorothalonil at concentrations ranging from 8.0 to 44 ng/mL, using TPN9A, a monoclonal antibody to chlorothalonil. The 50% inhibition concentration was 25 ng/mL. The reactivity was 10-fold lower than that of indirect competitive enzyme-linked immunosorbent assay (ic-ELISA). However, the SPR-sensor could determine chlorothalonil residues in vegetables at concentrations around the above MRLs. Chlorothalonil spiked in vegetables was recovered at 90-118% within 1 day and at 90-115% across 3 days, correlating with HPLC results. The sensor showed good performance for chlorothalonil residue analysis in vegetables with rapid determination, although the sensitivity and the cross-reactivity were less effective than with the ic-ELISA.

Affinity Sensing Strategies for the Detection of Pesticides in Food

“…Recoveries from 84.4% to 109% were obtained. Two immunosensors based on the SPR detection of fungicides have been presented by Hirakawa and co-workers [ 76 , 77 ]. In particular, an immunosensor for the detection of the fungicide boscalid in horticultural crops was developed and compared with a direct competitive enzyme-linked immunosorbent assay (dc-ELISA) [ 76 ].…”

“…Furthermore, the SPR-sensor exhibited performance comparable with the dc-ELISA, except for the sensitivity. Another immunosensor based on SPR was developed by the same group [ 77 ] to analyze chlorothalonil fungicides residues. In this case the SPR-sensor could determine chlorothalonil residues in vegetables at concentrations around the MRLs.…”

Development of an Immunosensor Based on Surface Plasmon Resonance for Simultaneous Residue Analysis of Three Pesticides —Boscalid, Clothianidin, and Nitenpyram— in Vegetables

“…The SPR immunosensor comprised a commercially available microflow-type instrument (Biacore T200; GE Healthcare Europe, Munich, Germany), and its sensor chip had four channels coated with carboxymethyl dextran (CM5; GE Healthcare Europe), as described previously. 20,27 The details are described in Supporting Information 2: "Constitution of SPR immunosensor", except for the sample preparation method and for the reaction method to establish simultaneous pesticide residue analysis.…”

“…[22][23][24] Immunosensors based on surface plasmon resonance (SPR immunosensors) have also been developed to determine pesticides. 20,[25][26][27] Since SPR immunosensors especially enable real-time monitoring of the antigen-antibody interaction in contrast to the above dcELISAs and electrochemical immunosensors, they are expected to be applicable to pesticide residue analysis in fresh vegetables that will be quickly distributed. However, there have been no reports of any SPR immunosensor for the simultaneous and rapid analysis of pesticides, although it involves required techniques.…”

Development of Enzyme-Linked Immunosorbent Assay for Analysis of Total Aflatoxins Based on Monoclonal Antibody Reactive with Aflatoxins B₁, B₂, G₁ and G₂

“…The dc-ELISA was conducted as described previously. 29 AFG 1 , AFG 2 in 10 (v/v) methanol were prepared at various concentrations (12.5 pg/mL to 10 ng/mL). A mixture of AFs (AFB 1 : AFB 2 : AFG 1 : AFG 2 8 : 1 : 6 : 1) was also prepared for measurement of the standard curve of the dc-ELISA.…”