Rapid detection of Potato virus S using antibody-coated gold nanoparticles

In spite of existing of several methods for detection of viruses, time consuming is major limitation of them. So, developing faster and real time method is important to certificate the plant materials in quarantine stations and virus management. In the recent research, nanotechnology was employed to detect Potato virus S (PVS) using gold nanoparticles (AuNPs). Colloidal AuNPs were prepared through citrate reduction and conjugated to a specific antibody against PVS coat protein. Conjugation was optimized by changing the pH of AuNPs and antibody concentration. Antibody coated nanoparticles were used to detect different concentrations of antigen using spectrophotometry. After binding the antibody to the gold nanoparticles which cause an increase in particle size, the SPR peak was displaced in range of 4-5 nm and shifted from 524 to 530 nm. The binding of the antigen to the nanoparticle also caused a change in the particle size and an increase maximum absorbance from 530 to 539 nm. No spectral change were seen when PVY and CMV used as controls. This study is the first attempt of nanoparticle usage in quick and easy detection of PVS