Denatured Ricin Can Be Detected as Native Ricin by Immunological Methods,but Nontoxic In Vivo

Abstract: Ricin is a glycoprotein from Ricinus communis seeds. It is known to have diverse toxic effects on cells of different visceral organs. In the present study, we purified and denatured ricin in a boiling water bath for different time intervals. We further made an attempt to identify native and denatured ricin by immunobased detection systems. All the antigen/antibody‐based assays identified native and denatured ricin. On SDS–PAGE, only native ricin was observed. In western blotting, ricin boiled for 3.75 min gave a strong band on X‐ray film. On native polyacryl amide gel electrophoresis, native and denatured ricin gave ricin band in 60‐kDa region. The denatured ricin did cause mortality up to 25 mg/kg, while 5 and 10 μg/kg of native ricin caused 50% and 100% mortality, respectively. Detection of native and denatured ricin is very difficult, and the investigating agencies, forensic scientists, and analysts should be very careful while interpreting the results.