Ricin detection: Tracking active toxin

Abstract

Ricin is a plant toxin with high bioterrorism potential due to its natural abundance and potency in inducing cell death. Early detection of the active toxin is essential for developing appropriate countermeasures. Here we review concepts for designing ricin detection methods, including mechanism of action of the toxin, advantages and disadvantages of current detection assays, and perspectives on the future development of rapid and reliable methods for detecting ricin in environmental samples.

Biological toxins of potential bioterrorism risk: Current status of detection and identification technology

“…Information on human aerosolized exposure is not available in open literature, but data from animal models indicate that this exposure route is expected to induce extremely severe effects on the respiratory tract and to cause death within days [14]. Under the aspect of bioterrorism, ricin is an agent of high concern since attempts of illicit production and/or release are regularly recorded worldwide [15]. Ricin is one of the two toxins (besides STX) listed by the CWC as a schedule 1 compound and its possession or purification is strictly regulated by the Organisation for the Prohibition of Chemical Weapons (OPCW).…”

“…For screening purposes, mostly sandwich enzymelinked immunosorbent assays (ELISAs) are being used, detecting the presence of the protein and reaching detection limits from ng/mL to fg/mL depending on the antibodies and the read-out system used [19], where ultrasensitive detection has been obtained by using the proprietary single molecule array technology [20]. A less sensitive, but much faster approach is on-site detection assays such as lateral flow assays (LFA) or biosensor approaches based on different principles and read-outs that usually reach detection limits in the ng/mL range within about 30 min [15]. For identification of ricin, sophisticated MS-based approaches have been established that combine immunoaffinity enrichment, quantification, and activity measurement by detecting the adenine release from artificial [89] (A-chain red ribbon, B-chain blue ribbon, interchain disulfide bridge yellow sticks, N-glycan in B-chain grey sticks, lactose orange ball/sticks, adenyl-guanosine green ball/sticks presentation) and seeds of the plant Ricinus communis (insert).…”

“…For detection and identification of ricin, an ever-increasing number of different technical approaches has been published based on immunological, mass spectrometric (MS), or functional approaches [4,15]. For screening purposes, mostly sandwich enzymelinked immunosorbent assays (ELISAs) are being used, detecting the presence of the protein and reaching detection limits from ng/mL to fg/mL depending on the antibodies and the read-out system used [19], where ultrasensitive detection has been obtained by using the proprietary single molecule array technology [20].…”

Forensic Files: Ricin Toxin, A Category B Bioterrorism Agent

“…Likewise, in 2013, Shannon Richardson was arrested for sending ricin laced letters to politicians including President Obama and New York City Mayor Michael Bloomberg [51]. Notable examples involving the biological toxin ricin are nicely summarized by Bozza et al, [52].…”

“…Several different methods toward ricin detection have been described [52]. These methods aim to detect both biologically active ricin, as well as methods that exploit the intrinsic physical and biochemical properties associated with the toxin.…”