{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,13]],"date-time":"2026-10-13T06:25:54Z","timestamp":1791872754588,"version":"4.3.4"},"reference-count":70,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2017,10,12]],"date-time":"2017-10-12T00:00:00Z","timestamp":1507766400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>A polyelectrolyte complex system of chitosan-pectin nano- and microparticles was developed to encapsulate the hormone insulin. The aim of this work was to obtain small particles for oral insulin delivery without chemical crosslinkers based on natural and biodegradable polysaccharides. The nano- and microparticles were developed using chitosans (with different degrees of acetylation: 15.0% and 28.8%) and pectin solutions at various charge ratios (n+\/n\u2212 given by the chitosan\/pectin mass ratio) and total charge. Nano- and microparticles were characterized regarding particle size, zeta potential, production yield, encapsulation efficiency, stability in different media, transmission electron microscopy and cytotoxicity assays using Caco-2 cells. The insulin release was evaluated in vitro in simulated gastric and intestinal media. Small-sized particles (~240\u2013~1900 nm) with a maximum production yield of ~34.0% were obtained. The highest encapsulation efficiency (~62.0%) of the system was observed at a charge ratio (n+\/n\u2212) 5.00. The system was stable in various media, particularly in simulated gastric fluid (pH 1.2). Transmission electron microscopy (TEM) analysis showed spherical shape particles when insulin was added to the system. In simulated intestinal fluid (pH 6.8), controlled insulin release occurred over 2 h. In vitro tests indicated that the proposed system presents potential as a drug delivery for oral administration of bioactive peptides.<\/jats:p>","DOI":"10.3390\/molecules22101707","type":"journal-article","created":{"date-parts":[[2017,10,12]],"date-time":"2017-10-12T13:06:19Z","timestamp":1507813579000},"page":"1707","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":115,"title":["Electrostatic Self-Assembled Chitosan-Pectin Nano- and Microparticles for Insulin Delivery"],"prefix":"10.3390","volume":"22","author":[{"given":"Vinicius","family":"Maciel","sequence":"first","affiliation":[{"name":"Faculty of Animal Science and Food Engineering, USP\u2014University of S\u00e3o Paulo, Av. Duque de Caxias Norte, 225, Pirassununga CEP 13635-900, S\u00e3o Paulo, Brazil"},{"name":"School of Chemical Engineering, UNICAMP\u2014State University of Campinas, Av. Albert Einstein, 500, Campinas CEP 13083-852, S\u00e3o Paulo, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Cristiana","family":"Yoshida","sequence":"additional","affiliation":[{"name":"Department of Exact and Earth Science, UNIFESP\u2014Federal University of S\u00e3o Paulo, Rua S\u00e3o Nicolau, 210, Diadema CEP 09913-030, S\u00e3o Paulo, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Susana","family":"Pereira","sequence":"additional","affiliation":[{"name":"Institut f\u00fcr Biologie und Biotechnologie der Pflanzen, Westf\u00e4lische Wilhelms\u2014Universit\u00e4t M\u00fcnster, Schlossgarten 3, 48149 M\u00fcnster, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7949-5429","authenticated-orcid":false,"given":"Francisco","family":"Goycoolea","sequence":"additional","affiliation":[{"name":"Institut f\u00fcr Biologie und Biotechnologie der Pflanzen, Westf\u00e4lische Wilhelms\u2014Universit\u00e4t M\u00fcnster, Schlossgarten 3, 48149 M\u00fcnster, Germany"},{"name":"School of Food Science and Nutrition, University of Leeds, Leeds LS2 9JT, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Telma","family":"Franco","sequence":"additional","affiliation":[{"name":"School of Chemical Engineering, UNICAMP\u2014State University of Campinas, Av. Albert Einstein, 500, Campinas CEP 13083-852, S\u00e3o Paulo, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2017,10,12]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"175","DOI":"10.1016\/j.ejpb.2007.01.013","article-title":"Preparation and characterization of free mixed-film of pectin\/chitosan\/Eudragit\u00ae RS intended for sigmoidal drug delivery","volume":"67","author":"Ghaffari","year":"2007","journal-title":"Eur. J. Pharm. 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