{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,13]],"date-time":"2026-01-13T05:56:49Z","timestamp":1768283809422,"version":"3.49.0"},"reference-count":34,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2015,5,19]],"date-time":"2015-05-19T00:00:00Z","timestamp":1431993600000},"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>Botulinum neurotoxins (BoNTs) cause the disease called botulism, which can be lethal. BoNTs are proteins secreted by some species of clostridia and are known to cause paralysis by interfering with nerve impulse transmission. Although the human lethal dose of BoNT is not accurately known, it is estimated to be between 0.1 \u03bcg to 70 \u03bcg, so it is important to enable detection of small amounts of these toxins. Our laboratory previously reported on the development of Endopep-MS, a mass-spectrometric\u2011based endopeptidase method to detect, differentiate, and quantify BoNT immunoaffinity purified from complex matrices.  In this work, we describe the application of Endopep-MS for the analysis of thirteen blinded samples supplied as part of the EQuATox proficiency test. This method successfully identified the presence or absence of BoNT in all thirteen samples and was able to successfully differentiate the serotype of BoNT present in the samples, which included matrices such as buffer, milk, meat extract, and serum. Furthermore, the method yielded quantitative results which had z-scores in the range of \u22123 to +3 for quantification of BoNT\/A containing samples. These results indicate that Endopep-MS is an excellent technique for detection, differentiation, and quantification of BoNT in complex matrices.<\/jats:p>","DOI":"10.3390\/toxins7051765","type":"journal-article","created":{"date-parts":[[2015,5,19]],"date-time":"2015-05-19T10:35:57Z","timestamp":1432031757000},"page":"1765-1778","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":49,"title":["Recommended Mass Spectrometry-Based Strategies to  Identify Botulinum Neurotoxin-Containing Samples"],"prefix":"10.3390","volume":"7","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8067-136X","authenticated-orcid":false,"given":"Suzanne","family":"Kalb","sequence":"first","affiliation":[{"name":"Centers for Disease Control and Prevention, 4770 Buford Hwy NE, Atlanta, GA 30341, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jakub","family":"Baudys","sequence":"additional","affiliation":[{"name":"Centers for Disease Control and Prevention, 4770 Buford Hwy NE, Atlanta, GA 30341, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Dongxia","family":"Wang","sequence":"additional","affiliation":[{"name":"Centers for Disease Control and Prevention, 4770 Buford Hwy NE, Atlanta, GA 30341, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"John","family":"Barr","sequence":"additional","affiliation":[{"name":"Centers for Disease Control and Prevention, 4770 Buford Hwy NE, Atlanta, GA 30341, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2015,5,19]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1617","DOI":"10.1016\/S0021-9258(17)42071-0","article-title":"Proteolysis of SNAP-25 by types E and A botulinal neurotoxins","volume":"269","author":"Binz","year":"1994","journal-title":"J. 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