{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,16]],"date-time":"2026-10-16T18:35:43Z","timestamp":1792175743913,"version":"4.4.0"},"reference-count":46,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2015,3,30]],"date-time":"2015-03-30T00:00:00Z","timestamp":1427673600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Marine Drugs"],"abstract":"<jats:p>The aim of the work reported herein was to investigate the effect of various low molecular weight chitosans (LMWCs) on the stability of insulin using USP HPLC methods. Insulin was found to be stable in a polyelectrolyte complex (PEC) consisting of insulin and LMWC in the presence of a Tris-buffer at pH 6.5. In the presence of LMWC, the stability of insulin increased with decreasing molecular weight of LMWC; 13 kDa LMWC was the most efficient molecular weight for enhancing the physical and chemical stability of insulin. Solubilization of insulin-LMWC polyelectrolyte complex (I-LMWC PEC) in a reverse micelle (RM) system, administered to diabetic rats, results in an oral delivery system for insulin with acceptable bioactivity.<\/jats:p>","DOI":"10.3390\/md13041765","type":"journal-article","created":{"date-parts":[[2015,3,30]],"date-time":"2015-03-30T10:50:23Z","timestamp":1427712623000},"page":"1765-1784","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":18,"title":["Low Molecular Weight Chitosan\u2013Insulin Polyelectrolyte Complex: Characterization and Stability Studies"],"prefix":"10.3390","volume":"13","author":[{"given":"Zakieh","family":"Al-Kurdi","sequence":"first","affiliation":[{"name":"The Jordanian Pharmaceutical Manufacturing Company (PLC), Suwagh Subsidiary for Drug Delivery Systems, P.O. Box 94, Naor 11710, Jordan"},{"name":"Faculty of Engineering & Science, University of Greenwich, Medway Campus, Chatham Maritime, Kent ME44TB, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Babur","family":"Chowdhry","sequence":"additional","affiliation":[{"name":"Faculty of Engineering & Science, University of Greenwich, Medway Campus, Chatham Maritime, Kent ME44TB, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Stephen","family":"Leharne","sequence":"additional","affiliation":[{"name":"Faculty of Engineering & Science, University of Greenwich, Medway Campus, Chatham Maritime, Kent ME44TB, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9801-5424","authenticated-orcid":false,"given":"Mahmoud","family":"Al Omari","sequence":"additional","affiliation":[{"name":"The Jordanian Pharmaceutical Manufacturing Company (PLC), Suwagh Subsidiary for Drug Delivery Systems, P.O. Box 94, Naor 11710, Jordan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Adnan","family":"Badwan","sequence":"additional","affiliation":[{"name":"The Jordanian Pharmaceutical Manufacturing Company (PLC), Suwagh Subsidiary for Drug Delivery Systems, P.O. Box 94, Naor 11710, Jordan"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2015,3,30]]},"reference":[{"key":"ref_1","first-page":"400","article-title":"Effect of additives on protein aggregation","volume":"19","author":"Hiroyuki","year":"2009","journal-title":"Curr. Pharm. Biotechnol."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"308","DOI":"10.2174\/138527210790231919","article-title":"Chitosan amphiphilic derivatives chemistry and applications","volume":"14","author":"Aranaz","year":"2010","journal-title":"Curr. Org. Chem."},{"key":"ref_3","doi-asserted-by":"crossref","unstructured":"Bernkop-Schn\u00fcrch, A. (2009). Oral Delivery of Macromolecular Drugs, Springer Dordrecht Heidelberg.","DOI":"10.1007\/978-1-4419-0200-9"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"2058","DOI":"10.1007\/s11095-005-8175-y","article-title":"Uptake and transport of PEG-graft-trimethyl-chitosan copolymer-insulin nanocomplexes by epithelial cells","volume":"22","author":"Mao","year":"2005","journal-title":"Pharm. Res."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"299","DOI":"10.1016\/j.ijpharm.2007.11.052","article-title":"Preparation, characterization and antibacterial activities of chitosan, N-trimethyl chitosan (TMC) and N-diethylmethyl chitosan (DEMC) nanoparticles loaded with insulin using both the ionotropic gelation and polyelectrolyte complexation methods","volume":"355","author":"Sadeghi","year":"2008","journal-title":"Int. J. Pharm."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"35","DOI":"10.1016\/S0939-6411(03)00160-7","article-title":"Structure and interactions in chitosan hydrogels formed by complexation or aggregation for biomedical application","volume":"57","author":"Berger","year":"2004","journal-title":"Eur. J. Pharm. Biopharm."},{"key":"ref_7","first-page":"1402","article-title":"Formation of polyelectrolyte complex particles from self-complexation of N-sulfated chitosan","volume":"10","author":"Schatz","year":"2009","journal-title":"Biomacromolecules"},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"1035","DOI":"10.1002\/jps.20520","article-title":"Self-assembled polyelectrolyte nanocomplexes between chitosan derivatives and insulin","volume":"95","author":"Mao","year":"2006","journal-title":"J. Pharm. Sci."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"146","DOI":"10.1021\/bm0607776","article-title":"Preparation and characterization of nanoparticles shelled with chitosan for oral insulin delivery","volume":"8","author":"Lin","year":"2007","journal-title":"Biomacromolecules"},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"240","DOI":"10.1016\/j.ijpharm.2007.05.015","article-title":"Peroral delivery of insulin using chitosan derivatives: A comparative study of polyelectrolyte nanocomplexes and nanoparticles","volume":"342","author":"Jintapattanakit","year":"2007","journal-title":"Int. J. Pharm."},{"key":"ref_11","first-page":"2127","article-title":"Nanolayer encapsulation of insulin-chitosan complexes improves efficiency of oral insulin delivery","volume":"9","author":"Song","year":"2014","journal-title":"Int. J. Nanomedicine"},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"1016","DOI":"10.1021\/js970018g","article-title":"Chitosan capsules for colon-specific drug delivery: Improvement of insulin absorption from the rat colon","volume":"86","author":"Tozaki","year":"1997","journal-title":"J. Pharm. Sci."},{"key":"ref_13","unstructured":"Badwan, A.A., Al-Remawi, M., El-Thaher, T., and Elsayed, A. (2007). Oral delivery of protein drugs using microemulsion. (EP1797870)."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"269","DOI":"10.1016\/j.ejpb.2009.06.004","article-title":"Formulation and characterization of an oily-based system for oral delivery of insulin","volume":"73","author":"Elsayed","year":"2009","journal-title":"Eur. J. Pharm. Biopharm."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"623","DOI":"10.1080\/01932691003659775","article-title":"Factors involved in formulation for proteins based on PEG-8 caprylic\/capric glycerides and polyglyceryl-6-diolate in a mixture of oleic acid with chitosan","volume":"32","author":"Assaf","year":"2011","journal-title":"J. Dispers. Sci. Technol."},{"key":"ref_16","unstructured":"(2013). United States Pharmacopeia, Unites States Pharmacopeia Convention."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"81","DOI":"10.1093\/chromsci\/23.2.81","article-title":"Separation and quantitation of insulins and related substances in bulk insulin crystals and in injectables by reversed-phase high performance liquid chromatography and the effect of temperature on the separation","volume":"23","author":"Smith","year":"1985","journal-title":"J. Chromatogr. Sci."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"611","DOI":"10.1211\/0022357023376","article-title":"On the stability of insulin delivered through a new glucose-responsive polymeric composite membrane","volume":"56","author":"Zhang","year":"2004","journal-title":"J. Pharm. Pharmacol."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"375","DOI":"10.1016\/j.ejpb.2004.10.006","article-title":"Strategic approaches for overcoming peptide and protein instability within biodegradable nano- and microparticles","volume":"59","author":"Bilati","year":"2005","journal-title":"Eur. J. Pharm. Biopharm."},{"key":"ref_20","unstructured":"ORA Laboratory Procedure. USFDA, Available online:http:\/\/www.fda.gov\/ScienceResearch\/ FieldScience\/ucm171877.htm."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"898","DOI":"10.1002\/bmc.616","article-title":"Development and validation of a rapid reversed-phase HPLC method for the determination of insulin from nanoparticulate systems","volume":"20","author":"Sarmento","year":"2006","journal-title":"Biomed. Chromatogr."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"825","DOI":"10.1248\/jhs.55.825","article-title":"Chromatographic analysis of conformationally changed insulin and its cytotoxic effect on PC12 cells","volume":"55","author":"Iwasa","year":"2009","journal-title":"J. Health Sci."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"107","DOI":"10.1016\/0301-4622(91)85011-E","article-title":"The self-association of zinc-free human insulin and insulin analogue B13-glutamine","volume":"39","author":"Hansen","year":"1991","journal-title":"Biophys. Chem."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"205","DOI":"10.1016\/0301-4622(91)85023-J","article-title":"Insulin association in neutral solution studied by light scattering","volume":"39","author":"Hvidt","year":"1991","journal-title":"Biophys. Chem."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"895","DOI":"10.1002\/bit.260400805","article-title":"Mechanism of insulin aggregation and stabilization in agitated aqueous solutions","volume":"40","author":"Sluzky","year":"1992","journal-title":"Biotechnol. Bioeng."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"344","DOI":"10.1111\/j.1399-3011.1990.tb01292.x","article-title":"Insulin aggregation in solution","volume":"36","author":"Dathe","year":"1990","journal-title":"Int. J. Pept. Protein Res."},{"key":"ref_27","first-page":"86","article-title":"The effect of buffers on protein conformational stability","volume":"9","author":"Ugwu","year":"2004","journal-title":"Pharm. Technol."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"923","DOI":"10.2337\/diacare.13.9.923","article-title":"Monomeric insulin and their experimental and clinical implications","volume":"13","author":"Brange","year":"1990","journal-title":"Diabetes Care"},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"727","DOI":"10.1023\/A:1015887001987","article-title":"Chemical stability of insulin. 2. Formation of higher molecular weight transformation products during storage of pharmaceutical preparations","volume":"9","author":"Brange","year":"1992","journal-title":"Pharm. Res."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"838","DOI":"10.2337\/diab.36.7.838","article-title":"Antibodies to covalent aggregates of insulin in blood of insulin-using diabetic patients","volume":"36","author":"Robbins","year":"1987","journal-title":"Diabetes"},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"728","DOI":"10.2337\/diab.39.6.728","article-title":"Persistent cutaneous insulin allergy resulting from high-molecular-weight insulin aggregates","volume":"39","author":"Ratner","year":"1990","journal-title":"Diabetes"},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"333","DOI":"10.1007\/s10856-005-0632-y","article-title":"Biomaterial with chemically engineered surface for protein immobilization","volume":"16","author":"Mansur","year":"2005","journal-title":"J. Mater. Sci. Mater Med."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"83","DOI":"10.3109\/02652049509051129","article-title":"Quality improvement of spray-dried, protein-loaded D,L-PLA microspheres by appropriate polymer solvent selection","volume":"12","author":"Gander","year":"1995","journal-title":"J. Microencapsul."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"420","DOI":"10.1023\/A:1012031012367","article-title":"The stability of recombinant human growth hormone in poly(lactic-co-glycolic acid) (PLGA) microspheres","volume":"14","author":"Cleland","year":"1997","journal-title":"Pharm. Res."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"926","DOI":"10.1021\/bm025539z","article-title":"Star-shaped poly(ethylene glycol)-block-polyethylenimine copolymers enhance DNA condensation of low molecular weight polyethylenimines","volume":"3","author":"Petersen","year":"2002","journal-title":"Biomacromolecules"},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"233","DOI":"10.1016\/S0141-8130(97)01165-3","article-title":"Effect of molecular weight and urea on the conformation of chitosan molecules in dilute solutions","volume":"20","author":"Tsaih","year":"1997","journal-title":"Int. J. Biol. Macromol."},{"key":"ref_37","first-page":"1684","article-title":"Polyelectrolyte complex\u2013An overview","volume":"4","author":"Verma","year":"2013","journal-title":"Int. J. Pharm. Sci. Res."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"131","DOI":"10.1016\/0168-3659(95)00146-8","article-title":"The potential of mucoadhesive polymers in enhancing intestinal peptide drug absorption .3. Effect of chitosan-glutamate and carbomer on epithelial tight junctions in vitro","volume":"39","author":"Borchard","year":"1996","journal-title":"J. Control. Release"},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"1396","DOI":"10.1002\/jps.10149","article-title":"Formulation pH modulates the interaction of insulin with chitosan nanoparticles","volume":"91","author":"Ma","year":"2002","journal-title":"J. Pharm. Sci."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"14222","DOI":"10.1021\/la403124u","article-title":"Strong adhesion and cohesion of chitosan in aqueous solutions","volume":"29","author":"Lee","year":"2013","journal-title":"Langmuir"},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"275","DOI":"10.1002\/jps.2600840303","article-title":"Evidence for a common intermediate in insulin deamidation and covalent dimer formation: Effects of pH and aniline trapping in dilute acidic solutions","volume":"84","author":"Anderson","year":"1995","journal-title":"J. Pharm. Sci."},{"key":"ref_42","doi-asserted-by":"crossref","unstructured":"Dubin, P., Bock, J., Davis, R., Schulz, D.N., and Thies, C. (1994). Macromolecular Complexes in Chemistry and Biology, Springer-Verlag.","DOI":"10.1007\/978-3-642-78469-9"},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"235","DOI":"10.1016\/j.ijpharm.2005.01.042","article-title":"Chitosan nanoparticles as a novel delivery system for ammonium glycyrrhizinate","volume":"295","author":"Wu","year":"2005","journal-title":"Int. J. Pharm."},{"key":"ref_44","doi-asserted-by":"crossref","first-page":"477","DOI":"10.1016\/j.carbpol.2006.11.006","article-title":"Calculation of Mark-Houwink-Sakurada (MHS) equation viscometric constants for chitosan in any solvent-temperature system using experimental reported viscometric constant data","volume":"68","author":"Kasaai","year":"2007","journal-title":"Carbohydr. Polym."},{"key":"ref_45","unstructured":"(2013). United States Pharmacopeia, Unites States Pharmacopeia Convention."},{"key":"ref_46","unstructured":"(1995). Validation of Analytical Methods, European Medicine Agency (EMA)."}],"container-title":["Marine Drugs"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1660-3397\/13\/4\/1765\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T20:44:05Z","timestamp":1760215445000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1660-3397\/13\/4\/1765"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2015,3,30]]},"references-count":46,"journal-issue":{"issue":"4","published-online":{"date-parts":[[2015,4]]}},"alternative-id":["md13041765"],"URL":"https:\/\/doi.org\/10.3390\/md13041765","relation":{},"ISSN":["1660-3397"],"issn-type":[{"value":"1660-3397","type":"electronic"}],"subject":[],"published":{"date-parts":[[2015,3,30]]}}}