{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,23]],"date-time":"2026-09-23T19:10:45Z","timestamp":1790190645607,"version":"4.1.0"},"reference-count":35,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2021,1,22]],"date-time":"2021-01-22T00:00:00Z","timestamp":1611273600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Toxins"],"abstract":"<jats:p>Ricin, a protein derived from the seeds of the castor bean plant (Ricinus communis), is a highly lethal toxin that inhibits protein synthesis, resulting in cell death. The widespread availability of ricin, its ease of extraction and its extreme toxicity make it an ideal agent for bioterrorism and self-poisoning. Thus, a rapid, sensitive and reliable method for ricin identification in clinical samples is required for applying appropriate and timely medical intervention. However, this goal is challenging due to the low predicted toxin concentrations in bio-fluids, accompanied by significantly high matrix interferences. Here we report the applicability of a sensitive, selective, rapid, simple and antibody-independent assay for the identification of ricin in body fluids using mass spectrometry (MS). The assay involves lectin affinity capturing of ricin by easy-to-use commercial lactose\u2013agarose (LA) beads, following by tryptic digestion and selected marker identification using targeted LC\u2013MS\/MS (Multiple Reaction Monitoring) analysis. This enables ricin identification down to 5 ng\/mL in serum samples in 2.5 h. To validate the assay, twenty-four diverse naive- or ricin-spiked serum samples were evaluated, and both precision and accuracy were determined. A real-life test of the assay was successfully executed in a challenging clinical scenario, where the toxin was identified in an abdominal fluid sample taken 72 h post self-injection of castor beans extraction in an eventual suicide case. This demonstrates both the high sensitivity of this assay and the extended identification time window, compared to similar events that were previously documented. This method developed for ricin identification in clinical samples has the potential to be applied to the identification of other lectin toxins.<\/jats:p>","DOI":"10.3390\/toxins13020079","type":"journal-article","created":{"date-parts":[[2021,1,25]],"date-time":"2021-01-25T12:28:31Z","timestamp":1611577711000},"page":"79","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":34,"title":["Rapid, Sensitive and Reliable Ricin Identification in Serum Samples Using LC\u2013MS\/MS"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-3612-1421","authenticated-orcid":false,"given":"Liron","family":"Feldberg","sequence":"first","affiliation":[{"name":"Department of Analytical Chemistry, Israel Institute for Biological Research, Ness Ziona 74100, Israel"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9704-2933","authenticated-orcid":false,"given":"Eytan","family":"Elhanany","sequence":"additional","affiliation":[{"name":"Department of Biochemistry and Molecular Genetics, Israel Institute for Biological Research, Ness Ziona 74100, Israel"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Orly","family":"Laskar","sequence":"additional","affiliation":[{"name":"Department of Infectious Diseases, Israel Institute for Biological Research, Ness Ziona 74100, Israel"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6379-9292","authenticated-orcid":false,"given":"Ofir","family":"Schuster","sequence":"additional","affiliation":[{"name":"Department of Infectious Diseases, Israel Institute for Biological Research, Ness Ziona 74100, Israel"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,1,22]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"65","DOI":"10.2165\/00139709-200322010-00007","article-title":"Ricin poisoning","volume":"22","author":"Bradberry","year":"2003","journal-title":"Toxicol. Rev."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"4416","DOI":"10.1021\/bi0474362","article-title":"Ricin A-chain activity on stem-loop and unstructured DNA substrates","volume":"44","author":"Amukele","year":"2005","journal-title":"Biochemistry"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"7912","DOI":"10.1016\/S0021-9258(19)57490-7","article-title":"Mannose receptor-mediated uptake of ricin toxin and ricin A chain by macrophages. Multiple intracellular pathways for a chain translocation","volume":"261","author":"Simmons","year":"1986","journal-title":"J. Biol. Chem."},{"key":"ref_4","doi-asserted-by":"crossref","unstructured":"Janik, E., Ceremuga, M., Saluk-Bijak, J., and Bijak, M. (2019). Biological Toxins as the Potential Tools for Bioterrorism. Int. J. Mol. Sci., 20.","DOI":"10.3390\/ijms20051181"},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"70","DOI":"10.1016\/j.forsciint.2010.12.013","article-title":"Analysis of active ricin and castor bean proteins in a ricin preparation, castor bean extract, and surface swabs from a public health investigation","volume":"209","author":"Schieltz","year":"2011","journal-title":"Forensic Sci. Int."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"1332","DOI":"10.3390\/toxins3101332","article-title":"Ricinus communis intoxications in human and veterinary medicine-a summary of real cases","volume":"3","author":"Worbs","year":"2011","journal-title":"Toxins"},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"T65","DOI":"10.1111\/j.1750-3841.2010.01570.x","article-title":"Thermal stability of ricin in orange and apple juices","volume":"75","author":"Jackson","year":"2010","journal-title":"J. Food Sci."},{"key":"ref_8","unstructured":"Centers for Disease Control and Prevention CDC (2003). Investigation of a ricin-containing envelope at a postal facility\u2014South Carolina, 2003. MMWR Morb. Mortal. Wkly. Rep., 52, 1129\u20131131."},{"key":"ref_9","unstructured":"Bioterrorism Agents\/Diseases (2017, December 03). Centers for Disease Control and Prevention 2018, Available online: https:\/\/emergency.cdc.gov\/agent\/agentlist-category.asp."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"e1","DOI":"10.1093\/jat\/bky100","article-title":"Lethal Injection of a Castor Bean Extract: Ricinine Quantification as a Marker for Ricin Exposure Using a Validated LC-MS\/MS Method","volume":"43","author":"Verougstraete","year":"2019","journal-title":"J. Anal. Toxicol."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"e67","DOI":"10.1016\/j.jemermed.2017.08.023","article-title":"Ricin Poisoning after Oral Ingestion of Castor Beans: A Case Report and Review of the Literature and Laboratory Testing","volume":"53","author":"Pizon","year":"2017","journal-title":"J. Emerg. Med."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"e13","DOI":"10.1016\/j.forsciint.2009.04.019","article-title":"Suicidal death after injection of a castor bean extract (Ricinus communis L.)","volume":"189","author":"Coopman","year":"2009","journal-title":"Forensic Sci. Int."},{"key":"ref_13","doi-asserted-by":"crossref","unstructured":"Falach, R., Sapoznikov, A., Alcalay, R., Aftalion, M., Ehrlich, S., Makovitzki, A., Agami, A., Mimran, A., Rosner, A., and Sabo, T. (2018). Generation of Highly Efficient Equine-Derived Antibodies for Post-Exposure Treatment of Ricin Intoxications by Vaccination with Monomerized Ricin. Toxins, 10.","DOI":"10.3390\/toxins10110466"},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"100","DOI":"10.1016\/j.toxicon.2017.01.009","article-title":"Extended therapeutic window for post-exposure treatment of ricin intoxication conferred by the use of high-affinity antibodies","volume":"127","author":"Alcalay","year":"2017","journal-title":"Toxicon Off. J. Int. Soc. Toxinology"},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"21","DOI":"10.1016\/j.jconrel.2016.05.018","article-title":"Development of a drug delivery system for efficient alveolar delivery of a neutralizing monoclonal antibody to treat pulmonary intoxication to ricin","volume":"234","author":"Respaud","year":"2016","journal-title":"J. Control. Release Off. J. Control. Release Soc."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"5147","DOI":"10.1007\/s00216-014-7710-2","article-title":"Identification and quantification of ricin in biomedical samples by magnetic immunocapture enrichment and liquid chromatography electrospray ionization tandem mass spectrometry","volume":"406","author":"Ma","year":"2014","journal-title":"Anal. Bioanal. Chem."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"313","DOI":"10.1093\/jat\/bkt026","article-title":"Serial ricinine levels in serum and urine after ricin intoxication","volume":"37","author":"Opstad","year":"2013","journal-title":"J. Anal. Toxicol."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"149","DOI":"10.1093\/jat\/29.3.149","article-title":"Quantification of ricinine in rat and human urine: A biomarker for ricin exposure","volume":"29","author":"Johnson","year":"2005","journal-title":"J. Anal. Toxicol."},{"key":"ref_19","first-page":"630","article-title":"Quantification of Ricinine and Abrine in Human Plasma by HPLC-MS-MS: Biomarkers of Exposure to Ricin and Abrin","volume":"42","author":"Isenberg","year":"2018","journal-title":"J. Anal. Toxicol."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"5157","DOI":"10.1007\/s00216-014-7934-1","article-title":"Development and validation of an ELISA kit for the detection of ricin toxins from biological specimens and environmental samples","volume":"406","author":"Chen","year":"2014","journal-title":"Anal. Bioanal. Chem."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"69","DOI":"10.1089\/15368590252917665","article-title":"Monoclonal antibody-based enzyme immunoassay for detection of ricin","volume":"21","author":"Shyu","year":"2002","journal-title":"Hybrid. Hybridomics"},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"398","DOI":"10.3390\/toxins3040398","article-title":"Detection of ricin contamination in ground beef by electrochemiluminescence immunosorbent assay","volume":"3","author":"Brandon","year":"2011","journal-title":"Toxins"},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"22","DOI":"10.1016\/j.ab.2016.04.018","article-title":"A biolayer interferometry-based assay for rapid and highly sensitive detection of biowarfare agents","volume":"506","author":"Mechaly","year":"2016","journal-title":"Anal. Biochem."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"375","DOI":"10.1007\/s11419-018-0414-0","article-title":"Identifying exposures to ribosome-inactivating proteins in blood samples: Amplification of ricin-induced ribosomal damage products enables sensitive detection of active toxin and circulating depurinated 28S rRNA","volume":"36","author":"Falach","year":"2018","journal-title":"Forensic Toxicol."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"72","DOI":"10.1007\/s11419-017-0377-6","article-title":"Determination of ricin intoxication in biological samples by monitoring depurinated 28S rRNA in a unique reverse transcription-ligase-polymerase chain reaction assay","volume":"36","author":"Israeli","year":"2018","journal-title":"Forensic Toxicol."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"4881","DOI":"10.3390\/toxins7124854","article-title":"Recommended Mass Spectrometry-Based Strategies to Identify Ricin-Containing Samples","volume":"7","author":"Kalb","year":"2015","journal-title":"Toxins"},{"key":"ref_27","doi-asserted-by":"crossref","unstructured":"Duracova, M., Klimentova, J., Fucikova, A., and Dresler, J. (2018). Proteomic Methods of Detection and Quantification of Protein Toxins. Toxins, 10.","DOI":"10.3390\/toxins10030099"},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"2037","DOI":"10.1021\/ac802769s","article-title":"Mass spectrometric detection of ricin and its activity in food and clinical samples","volume":"81","author":"Kalb","year":"2009","journal-title":"Anal. Chem."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"72","DOI":"10.1016\/j.toxicon.2015.01.003","article-title":"Quantification of ricin, RCA and comparison of enzymatic activity in 18 Ricinus communis cultivars by isotope dilution mass spectrometry","volume":"95","author":"Schieltz","year":"2015","journal-title":"Toxicon Off. J. Int. Soc. Toxinol."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"1529","DOI":"10.1021\/ac802240f","article-title":"Detection of intact ricin in crude and purified extracts from castor beans using matrix-assisted laser desorption ionization mass spectrometry","volume":"81","author":"Brinkworth","year":"2009","journal-title":"Anal. Chem."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"e4482","DOI":"10.1002\/jms.4482","article-title":"Rapid and sensitive identification of ricin in environmental samples based on lactamyl agarose beads using LC-MS\/MS (MRM)","volume":"55","author":"Feldberg","year":"2020","journal-title":"J. Mass Spectrom. JMS"},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"4987","DOI":"10.3390\/toxins7124859","article-title":"An International Proficiency Test to Detect, Identify and Quantify Ricin in Complex Matrices","volume":"7","author":"Worbs","year":"2015","journal-title":"Toxins"},{"key":"ref_33","unstructured":"European Comission (2002). 2002\/657\/EC: Commission Decision of 12 August 2002 implementing Council Directive 96\/23\/EC concerning the performance of analytical methods and the interpretation of results. Off. J. Eur. Communities, 221, 8\u201336."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"821","DOI":"10.1002\/jms.1953","article-title":"Determination of ricin by nano liquid chromatography\/mass spectrometry after extraction using lactose-immobilized monolithic silica spin column","volume":"46","author":"Kato","year":"2011","journal-title":"J. Mass Spectrom. JMS"},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"7153","DOI":"10.1128\/AAC.01696-16","article-title":"Potent Antiedematous and Protective Effects of Ciprofloxacin in Pulmonary Ricinosis","volume":"60","author":"Gal","year":"2016","journal-title":"Antimicrob. Agents Chemother."}],"container-title":["Toxins"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2072-6651\/13\/2\/79\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T05:13:50Z","timestamp":1760159630000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2072-6651\/13\/2\/79"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2021,1,22]]},"references-count":35,"journal-issue":{"issue":"2","published-online":{"date-parts":[[2021,2]]}},"alternative-id":["toxins13020079"],"URL":"https:\/\/doi.org\/10.3390\/toxins13020079","relation":{},"ISSN":["2072-6651"],"issn-type":[{"value":"2072-6651","type":"electronic"}],"subject":[],"published":{"date-parts":[[2021,1,22]]}}}