Ricin Analysis

Abstract

Ricin is a protein toxin produced by the castor bean plant, Ricinus communis . In vivo, the 64‐kDa ricin protein halts protein synthesis by depurinating 28S ribosomal RNA, rendering it unable to bind to elongation factor 2 (EF‐2). This halt in protein synthesis causes detrimental health effects and can lead to death upon exposure to ricin. Ricin is highly toxic and has the potential for high availability; therefore, it is considered a likely agent for bioterrorism. Hence, sensitive and selective analytical methods are desired to analyze for ricin in food, environmental, and clinical samples. This article reviews various published methods to detect ricin. These methods are numerous but can be loosely grouped into animal assays, detection of ricin DNA, immunoassays, mass‐spectrometry‐based amino acid composition methods, and detection of ricin enzymatic activity. These various methods have different purposes. Some methods function as rapid screens with moderate false positive and false negative rates, whereas others serve as confirmatory assays. In this article, the methods are explained and compared, with discussion on the sensitivity and selectivity of the methods.