{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,2]],"date-time":"2026-07-02T00:07:40Z","timestamp":1782950860769,"version":"3.54.5"},"reference-count":23,"publisher":"Public Library of Science (PLoS)","issue":"6","license":[{"start":{"date-parts":[[2025,6,4]],"date-time":"2025-06-04T00:00:00Z","timestamp":1748995200000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["www.plosone.org"],"crossmark-restriction":false},"short-container-title":["PLoS One"],"abstract":"\nBackground<\/jats:title>\nInsulin, a peptide hormone crucial for diabetes management, necessitates strict storage (2-8o<\/jats:sup>C) to maintain concentration, as per regulatory guidelines (e.g., USP, WHO). Degradation can occur during manufacturing process, and transportation or storage, via heat-induced denaturation and aggregation, compromises its efficacy. In Sub-Saharan Africa, including Tanzania, weak regulatory oversight of imported medicines may compromise insulin quality. Varied findings from existing studies underline the need for local quality assessments.<\/jats:p>\n<\/jats:sec>\n\nMethods<\/jats:title>\nThis cross-sectional study, conducted from April to July 2024 in Mwanza, Tanzania, evaluated the quality of insulin from eight pharmacies. A convenience sampling approach was employed, with insulin samples purchased as a simulated patient to reflect real-world acquisition. 15 samples, representing seven distinct insulin brands, were collected. High-Performance Liquid Chromatography (HPLC) was utilized to quantify insulin concentration. Additionally, samples were assessed for visual appearance, packaging, labeling, and storage conditions following established pharmacopoeial and quality control standards.<\/jats:p>\n<\/jats:sec>\n\nResults<\/jats:title>\nOut of 15 insulin samples, two samples (13.3%) failed to meet the official USP monograph during the assay test. The remaining samples 13 (86.7%) complied with USP standards.<\/jats:p>\n<\/jats:sec>\n\nConclusion<\/jats:title>\nThese findings underline significant challenges in ensuring the quality of insulin products. While most samples adhered to USP standards, the issues observed highlight the need for improved quality control measures and robust cold chain management to guarantee the efficacy and reliability of insulin for diabetic patients.<\/jats:p>\n<\/jats:sec>","DOI":"10.1371\/journal.pone.0325366","type":"journal-article","created":{"date-parts":[[2025,6,4]],"date-time":"2025-06-04T18:01:49Z","timestamp":1749060109000},"page":"e0325366","update-policy":"https:\/\/doi.org\/10.1371\/journal.pone.corrections_policy","source":"Crossref","is-referenced-by-count":2,"title":["Quality of insulin obtained from hospital and community pharmacies in Mwanza Tanzania: A cross-sectional study"],"prefix":"10.1371","volume":"20","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-3123-0477","authenticated-orcid":true,"given":"Emmanuel","family":"Kimaro","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Eveline T.","family":"Konje","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Benson R.","family":"Kidenya","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Amani T.","family":"Mori","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6008-3539","authenticated-orcid":true,"given":"Eliangiringa","family":"Kaale","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"340","published-online":{"date-parts":[[2025,6,4]]},"reference":[{"issue":"2","key":"pone.0325366.ref001","article-title":"History of insulin","volume":"2","author":"CC Quianzon","year":"2012","journal-title":"J Community Hosp Intern Med Perspect"},{"key":"pone.0325366.ref002"},{"issue":"1","key":"pone.0325366.ref003","doi-asserted-by":"crossref","first-page":"147","DOI":"10.1177\/1932296819900258","article-title":"Insulin storage: a critical reappraisal","volume":"15","author":"L Heinemann","year":"2021","journal-title":"J Diabetes Sci Technol"},{"key":"pone.0325366.ref004","volume-title":"USP-NF insulin injection","author":"Monograph U","year":"2020"},{"issue":"10","key":"pone.0325366.ref005","doi-asserted-by":"crossref","first-page":"325","DOI":"10.4236\/pp.2017.810024","article-title":"Assessment of medicines cold chain storage conformity with the world health organization requirements in health facilities in Tanzania","volume":"8","author":"S Ringo","year":"2017","journal-title":"Pharmacol Pharmacy"},{"issue":"2","key":"pone.0325366.ref006","doi-asserted-by":"crossref","DOI":"10.1371\/journal.pone.0245372","article-title":"Heat-stability study of various insulin types in tropical temperature conditions: New insights towards improving diabetes care","volume":"16","author":"B Kaufmann","year":"2021","journal-title":"PLoS One"},{"issue":"3","key":"pone.0325366.ref007","first-page":"149","article-title":"Chemical stability of insulin. 3. Influence of excipients, formulation, and pH","volume":"4","author":"J Brange","year":"1992","journal-title":"Acta Pharm Nord"},{"key":"pone.0325366.ref008","doi-asserted-by":"crossref","unstructured":"Davies JG, Gao D, Kim Y, Harris R, Cash P, Schofield T, et al. ICH Q5C stability testing of biotechnological. biological products. 2017:345.","DOI":"10.1002\/9781118971147.ch12"},{"issue":"8","key":"pone.0325366.ref009","doi-asserted-by":"crossref","first-page":"2255","DOI":"10.1002\/jps.24039","article-title":"Effects of phenol and meta-cresol depletion on insulin analog stability at physiological temperature","volume":"103","author":"BM Teska","year":"2014","journal-title":"J Pharm Sci"},{"key":"pone.0325366.ref010","unstructured":"Stability testing ofnew drug substances and products q1a (r2). International conference on harmonisation of technical requirements for registration of pharmaceuticals for human USE; 2003."},{"issue":"1","key":"pone.0325366.ref011","article-title":"Insulin storage by patients with diabetes mellitus in Jos, Nigeria","volume":"9","author":"FH Puepet","year":"2007","journal-title":"J Med Trop"},{"key":"pone.0325366.ref012","doi-asserted-by":"crossref","first-page":"7559984","DOI":"10.1155\/2021\/7559984","article-title":"Cold chain management by healthcare providers at a district in Ghana: a mixed methods study","volume":"2021","author":"A Asamoah","year":"2021","journal-title":"Biomed Res Int"},{"key":"pone.0325366.ref013","author":"World Health Organization","year":"2015"},{"issue":"3","key":"pone.0325366.ref014","doi-asserted-by":"crossref","DOI":"10.1371\/journal.pmed.1000052","article-title":"Guidelines for field surveys of the quality of medicines: a proposal","volume":"6","author":"PN Newton","year":"2009","journal-title":"PLoS Med"},{"issue":"2","key":"pone.0325366.ref015","first-page":"40","article-title":"Development and validation of HPLC method for determination of human insulin in pharmaceutical preparation","volume":"2","author":"B Yilmaz","year":"2010","journal-title":"Int J Pharmaceutical Sci Rev Res"},{"issue":"7","key":"pone.0325366.ref016","doi-asserted-by":"crossref","first-page":"505","DOI":"10.1093\/jat\/bkz014","article-title":"Validation of a fully automated immunoaffinity workflow for the detection and quantification of insulin analogs by LC-MS-MS in postmortem vitreous humor","volume":"43","author":"KM Legg","year":"2019","journal-title":"J Anal Toxicol"},{"key":"pone.0325366.ref017","doi-asserted-by":"crossref","DOI":"10.1093\/rheumatology\/kex278","article-title":"The process defines the product: what really matters in biosimilar design and production?","volume":"56","author":"AG Vulto","year":"2017","journal-title":"Rheumatology (Oxford)"},{"key":"pone.0325366.ref018","doi-asserted-by":"crossref","first-page":"45","DOI":"10.2147\/BS.S36043","article-title":"Production and manufacturing of biosimilar insulins: implications for patients, physicians, and health care systems","author":"MK Kuhlmann","year":"2014","journal-title":"Biosimilars"},{"key":"pone.0325366.ref019","article-title":"Regulatory verification by Health Canada of content in recombinant human insulin, human insulin analog, and porcine insulin drug products in the Canadian market using validated pharmacopoeial methods over nonvalidated approaches","author":"B Lorbetskie","year":"2023","journal-title":"J Diabetes Sci Technol"},{"issue":"6","key":"pone.0325366.ref020","doi-asserted-by":"crossref","first-page":"1360","DOI":"10.2337\/dc19-1941","article-title":"Commercially available insulin products demonstrate stability throughout the cold supply chain across the U.S","volume":"43","author":"TJ Garrett","year":"2020","journal-title":"Diabetes Care"},{"issue":"29","key":"pone.0325366.ref021","doi-asserted-by":"crossref","first-page":"8021","DOI":"10.1021\/acs.jpcb.1c01997","article-title":"Insulin fibril formation caused by mechanical shock and cavitation","volume":"125","author":"H Wu","year":"2021","journal-title":"J Phys Chem B"},{"issue":"2","key":"pone.0325366.ref022","doi-asserted-by":"crossref","first-page":"1306","DOI":"10.3390\/ijms24021306","article-title":"Peptide inhibitors of insulin fibrillation: current and future challenges","volume":"24","author":"B Rosetti","year":"2023","journal-title":"Int J Mol Sci"},{"key":"pone.0325366.ref023","author":"Organization WH","year":"2020"}],"container-title":["PLOS One"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/dx.plos.org\/10.1371\/journal.pone.0325366","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,6,4]],"date-time":"2025-06-04T18:01:54Z","timestamp":1749060114000},"score":1,"resource":{"primary":{"URL":"https:\/\/dx.plos.org\/10.1371\/journal.pone.0325366"}},"subtitle":[],"editor":[{"given":"Christophe","family":"Curti","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"editor"}]}],"short-title":[],"issued":{"date-parts":[[2025,6,4]]},"references-count":23,"journal-issue":{"issue":"6","published-online":{"date-parts":[[2025,6,4]]}},"URL":"https:\/\/doi.org\/10.1371\/journal.pone.0325366","relation":{},"ISSN":["1932-6203"],"issn-type":[{"value":"1932-6203","type":"electronic"}],"subject":[],"published":{"date-parts":[[2025,6,4]]}}}