Recommended Immunological Assays to Screen for Ricin-Containing Samples

Area of Science:

• Toxicology
• Biodefense
• Analytical Chemistry

Background:

• Ricin, a highly toxic agent from Ricinus communis, is a CDC Category B biological weapon.
• Its availability and lack of treatments necessitate reliable detection methods.
• Ricin shares homology with Ricinus communis agglutinin (RCA120), complicating differentiation.

Purpose of the Study:

• To assess international laboratory capabilities in detecting and quantifying ricin.
• To evaluate the differentiation of ricin from the similar protein RCA120.
• To benchmark various immunological detection strategies.

Main Methods:

• An international proficiency test (PT) involving 17 expert laboratories.
• Utilized six analytical strategies based on immunological assays.
• Included four immunoenzymatic assays and two immunochromatographic tests.

Main Results:

• All participating laboratories successfully identified samples containing ricin and/or RCA120.
• Detection and quantification of both ricin and RCA120 were achieved using various antibodies.
• Immunological methods demonstrated high sensitivity and precision for ricin analysis.

Conclusions:

• Immunological assays are effective for detecting and quantifying ricin and RCA120.
• The proficiency test validated the performance of diverse immunological approaches.
• These methods are recommended for sensitive and precise ricin quantification in biodefense applications.