{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,3]],"date-time":"2026-10-03T03:34:22Z","timestamp":1790998462341,"version":"4.1.0"},"reference-count":40,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2022,4,6]],"date-time":"2022-04-06T00:00:00Z","timestamp":1649203200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Biosensors"],"abstract":"<jats:p>Botulinum neurotoxin type A (BoNT-A) is the active substance in pharmaceutical preparations widely used worldwide for the highly effective treatment of various disorders. Among the three commercial formulations of BoNT-A currently available in Italy for neurological indications, abobotulinum A toxin (Dysport\u00ae, Ipsen SpA, Milano, Italy) and incobotulinum A toxin (Xeomin\u00ae, Merz Pharma Italia srl, Milano, Italy) differ in the content of neurotoxin, non-toxic protein, and excipients. Clinical applications of BoNT-A adopt extremely diluted solutions (10\u22126 mg\/mL) for injection in the target body district. Near-infrared spectroscopy (NIRS) and chemometrics allow rapid, non-invasive, and non-destructive methods for qualitative and quantitative analysis. No data are available to date on the chemometric analysis of the spectral fingerprints acquired from the diluted commercial formulations of BoNT-A. In this proof-of-concept study, we tested whether NIRS can categorize solutions of incobotulinum A toxin (lacking non-toxic proteins) and abobotulinum A toxin (containing non-toxic proteins). Distinct excipients in the two formulations were also analyzed. We acquired transmittance spectra in the visible and short-wave infrared regions (350\u20132500 nm) by an ASD FieldSpec 4\u2122 Standard-Res Spectrophotoradiometer, using a submerged dip probe designed to read spectra in transflectance mode from liquid samples. After preliminary spectra pre-processing, principal component analysis was applied to characterize the spectral features of the two BoNT-A solutions and those of the various excipients diluted according to clinical standards. Partial least squares-discriminant analysis was used to implement a classification model able to discriminate the BoNT-A solutions and excipients. NIRS distinguished solutions containing distinct BoNT-A commercial formulations (abobotulinum A toxin vs. incobotulinum A toxin) diluted at recommended volumes for clinical reconstitution, distinct proteins (HSA vs. incobotulinum A toxin), very diluted solutions of simple sugars (lactose vs. sucrose), and saline or water. Predictive models of botulinum toxin formulations were also performed with the highest precision and accuracy.<\/jats:p>","DOI":"10.3390\/bios12040216","type":"journal-article","created":{"date-parts":[[2022,4,6]],"date-time":"2022-04-06T16:21:30Z","timestamp":1649262090000},"page":"216","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":8,"title":["Near-Infrared Transflectance Spectroscopy Discriminates Solutions Containing Two Commercial Formulations of Botulinum Toxin Type A Diluted at Recommended Volumes for Clinical Reconstitution"],"prefix":"10.3390","volume":"12","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-7945-8342","authenticated-orcid":false,"given":"Antonio","family":"Curr\u00e0","sequence":"first","affiliation":[{"name":"Academic Neurology Unit, Department of Medico-Surgical Sciences and Biotechnologies, Sapienza University of Rome, 04019 Terracina, Italy"},{"name":"Research Center for Biophotonics, Sapienza University of Rome, 04100 Latina, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4739-1582","authenticated-orcid":false,"given":"Riccardo","family":"Gasbarrone","sequence":"additional","affiliation":[{"name":"Ce.R.S.I.Te.S.\u2014Research and Service Center for Sustainable Technological Innovation, Sapienza University of Rome, 04100 Latina, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6935-2686","authenticated-orcid":false,"given":"Giuseppe","family":"Bonifazi","sequence":"additional","affiliation":[{"name":"Research Center for Biophotonics, Sapienza University of Rome, 04100 Latina, Italy"},{"name":"Department of Chemical Engineering, Materials & Environment, Sapienza University of Rome, 00184 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2435-5212","authenticated-orcid":false,"given":"Silvia","family":"Serranti","sequence":"additional","affiliation":[{"name":"Research Center for Biophotonics, Sapienza University of Rome, 04100 Latina, Italy"},{"name":"Department of Chemical Engineering, Materials & Environment, Sapienza University of Rome, 00184 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Francesco","family":"Fattapposta","sequence":"additional","affiliation":[{"name":"Neurology Unit, Policlinico Umberto I, Department of Human Neurosciences, Sapienza University of Rome, 00185 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3419-0669","authenticated-orcid":false,"given":"Carlo","family":"Trompetto","sequence":"additional","affiliation":[{"name":"Department of Neuroscience, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health, University of Genoa, 16132 Genova, Italy"},{"name":"Department of Neuroscience, Division of Neurorehabilitation, IRCCS Ospedale Policlinico San Martino, 16132 Genova, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0620-7654","authenticated-orcid":false,"given":"Lucio","family":"Marinelli","sequence":"additional","affiliation":[{"name":"Department of Neuroscience, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health, University of Genoa, 16132 Genova, Italy"},{"name":"Department of Neuroscience, Division of Clinical Neurophysiology, IRCCS Ospedale Policlinico San Martino, 16132 Genova, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2056-0104","authenticated-orcid":false,"given":"Paolo","family":"Missori","sequence":"additional","affiliation":[{"name":"Neurosurgery Unit, Policlinico Umberto I, Department of Human Neurosciences, Sapienza University of Rome, 00185 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Eugenio","family":"Lendaro","sequence":"additional","affiliation":[{"name":"Pathology Unit I.C.O.T., Department of Medical-Surgical Sciences and Bio-Technologies, Sapienza University of Rome, 04100 Latina, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,4,6]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1703","DOI":"10.1016\/S0041-0101(01)00157-X","article-title":"Clostridium botulinum and its neurotoxins: A metabolic and cellular perspective","volume":"39","author":"Johnson","year":"2001","journal-title":"Toxicon"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"10","DOI":"10.4103\/0975-5950.196133","article-title":"Botulinum toxin the poison that heals: A brief review","volume":"7","author":"Singh","year":"2016","journal-title":"Natl. 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