Rapid Detection of Ricin by Sensitising Carboxylated Latex Particles by Ricin Antibodies

Abstract

Ricin is a highly toxic glycoprotein of Ricinus communis seeds. The toxin was purified and antisera was raised against ricin in rabbit. Polyclonal antibodies were covalently coupled through
a water soluble carbodiimide to carboxylated latex particles in various concentrations (800 pg to 3200 pg proteid0.5 ml). Maximum antibodies binding was obtained at 2400 pg to 3200 pg
proteid0.5 ml of 2 per cent (wtlvol) latex particles with a sensitivity of 200 pg toxin per test (9 pglml). The sensitivity of latex agglutination test increased as amount of protein bound to
the latex particles increased. The optimum sensitivity of test was recorded when latex particles were sensitised with 2800 pg proteid0.5 ml of latex particles. The reagents were stable for one year without loss of its sensitivity. Developed latex agglutination test is rapid, sensitive, and also does not require trained personnel and costly equipment.