Determination of microcystin-LR in surface water by a magnetic bead-based colorimetric immunoassay using antibody-conjugated gold nanoparticles

Abstract

Herein we describe the development of a homogeneous competitive colorimetric immunoassay using antigen-functionalized magnetic beads (MBs) and antibody-immobilized gold nanoparticles (AuNPs) combined with the established gold staining method for the determination of microcystin-leucine-arginine (MC-LR) in surface water.

Cloning and plant‐based production of antibody MC10E7 for a lateral flow immunoassay to detect [4‐arginine]microcystin in freshwater

“…The MC‐LR‐BSA conjugate was synthesized as recently described (Neumann et al ., ). In brief, sulfhydryl groups were introduced to BSA with N ‐succinimidyl 3‐(acetylthio)‐propionate (SATP) and used to couple the MC‐LR via its dehydroalanine residue (the Michael acceptor) to the protein.…”

“…The colloidal gold probe was prepared according to Frens with slight modification as described previously (Frens, ; Neumann et al ., ). An average particle diameter of 40 nm was obtained by mixing 50 mL water, 188 μL HAuCl 4 (0.1 m in water) and 1.13 mL of aqueous sodium citrate solution (1% in water).…”

Microcystin-LR Enrichment from Freshwater by a Recombinant Plant-derived Antibody Using Sol-Gel-Glass Immunoextraction

“…The microtiter plates were coated with the MC-LR-BSA conjugate (50 ng mL -1 in coating buffer, 200 μL/well; coating buffer of pH 9.6 consisted of 1.6 g Na2CO3, 2.9 g NaHCO3 and 0.2 g NaN3 in 1 L of water) over night at 4 C. (Note: The conjugate was prepared via a Michael addition, yielding a coupling rate of 3 microcystin residues per mole of protein. The details are described in Neumann et al) 60 Further steps were performed at RT. The wells were washed automatically with a washing buffer and blocked with casein (300 μL/well) for 1 h on an orbital shaker at 200 rpm.…”

Synthesis of magnetic core–shell Fe3O4@PDA@Cu-MOFs composites for enrichment of microcystin-LR by MALDI-TOF MS analysis

“…To ensure water quality, several methods and techniques have been applied for MC-LR detection in water. Some of them are colorimetric aptamer assay, [11][12][13] high-performance liquid chromatography (HPLC), 14 enzyme-linked immunosorbent assay, 15,16 uorescence biosensor immunoassay, 17,18 electrochemical. [19][20][21] Although these methods can detect exceedingly low levels of MC-LR, they always require harmful solvents and time-consuming, skilled and complex operating procedures.…”