title: Design, characterisation, and bioefficiency of insulin-chitosan nanoparticles after stabilisation by freeze-drying or cross-linking.
abstract: Insulin delivery by oral route would be ideal, but has no effect, due to the harsh conditions of the gastrointestinal tract. Protection of insulin using encapsulation in self-assembled particles is a promising approach. However, the lack of stability of this kind of particles in biological environments induces a low bioavailability of encapsulated insulin after oral administration. The objective of this work was to evaluate the effect of two stabilisation strategies alone or combined, freeze-drying and cross-linking, on insulin-loaded chitosan NPs, and to determine their bioefficiency in vitro and in vivo. NPs were prepared by complex coacervation between insulin and chitosan, stabilised either by cross linking with sodium tripolyphosphate solution (TPP), by freeze-drying or both treatments. In vitro bioefficiency NP uptake was evaluated by flow cytometry on epithelial models (Caco-2/RevHT29MTX (mucus secreting cells)). In vivo, NPs were injected via catheter in the peritoneum or duodenum on insulinopenic rats. Freeze-drying increased in size and charge (+15% vs control 412 ± 7 nm; + 36 ± 0.3 mV) in comparison with cross linking which decreased NP size (-25%) without impacting the NP charge. When combined the consecutive treatments reduced NPs size and increased charges as compared to standard level. Freeze drying is necessary to prevent the destruction of NP in intestinal environment in comparison with no freeze dryed one where 60% of NP were destroyed after 2h. Additionally freeze drying combined with cross linking treatments improved bioefficiency of NP with uptake in cell increased when mucus is present. Combination of both treatment showed a protection of insulin in vivo, with a reduction of glycemia when NPs were administrated. This work showed that the combination of freeze drying and cross linking treatment is necessary to stabilize (freeze-drying) and increase bioefficiency (cross-linking) of self assembled NP in the delivery of insulin in vitro and in vivo.
authors.affiliation: UMR DIATHEC, EA 7294, Centre Européen d'Etude du Diabète, Université de Strasbourg, Fédération de Médecine Translationnelle de Strasbourg, Bld René Leriche, 67200 Strasbourg, France.
authors.forename: M
authors.initials: M
authors.lastname: Diop
authors.affiliation: Institut Charles Sadron (UPR 22CNRS), 23 rue du Loess BP 84047, 67034 Strasbourg Cedex 2, France.
authors.forename: N
authors.initials: N
authors.lastname: Auberval
authors.affiliation: UMR DIATHEC, EA 7294, Centre Européen d'Etude du Diabète, Université de Strasbourg, Fédération de Médecine Translationnelle de Strasbourg, Bld René Leriche, 67200 Strasbourg, France.
authors.forename: A
authors.initials: A
authors.lastname: Viciglio
authors.affiliation: UMR DIATHEC, EA 7294, Centre Européen d'Etude du Diabète, Université de Strasbourg, Fédération de Médecine Translationnelle de Strasbourg, Bld René Leriche, 67200 Strasbourg, France.
authors.forename: A
authors.initials: A
authors.lastname: Langlois
authors.affiliation: UMR DIATHEC, EA 7294, Centre Européen d'Etude du Diabète, Université de Strasbourg, Fédération de Médecine Translationnelle de Strasbourg, Bld René Leriche, 67200 Strasbourg, France.
authors.forename: W
authors.initials: W
authors.lastname: Bietiger
authors.affiliation: UMR DIATHEC, EA 7294, Centre Européen d'Etude du Diabète, Université de Strasbourg, Fédération de Médecine Translationnelle de Strasbourg, Bld René Leriche, 67200 Strasbourg, France.
authors.forename: C
authors.initials: C
authors.lastname: Mura
authors.affiliation: UMR DIATHEC, EA 7294, Centre Européen d'Etude du Diabète, Université de Strasbourg, Fédération de Médecine Translationnelle de Strasbourg, Bld René Leriche, 67200 Strasbourg, France.
authors.forename: C
authors.initials: C
authors.lastname: Peronet
authors.affiliation: Institut Charles Sadron (UPR 22CNRS), 23 rue du Loess BP 84047, 67034 Strasbourg Cedex 2, France.
authors.forename: A
authors.initials: A
authors.lastname: Bekel
authors.affiliation: Institut Pluridisciplinaire Hubert Curien (UMR 7178CNRS/CNRS), 74 route du Rhin, 67400 Illkirch, France.
authors.forename: D
authors.initials: D
authors.lastname: Julien David
authors.affiliation: Institut Pluridisciplinaire Hubert Curien (UMR 7178CNRS/CNRS), 74 route du Rhin, 67400 Illkirch, France.
authors.forename: M
authors.initials: M
authors.lastname: Zhao
authors.affiliation: UMR DIATHEC, EA 7294, Centre Européen d'Etude du Diabète, Université de Strasbourg, Fédération de Médecine Translationnelle de Strasbourg, Bld René Leriche, 67200 Strasbourg, France.
authors.forename: M
authors.initials: M
authors.lastname: Pinget
authors.affiliation: UMR DIATHEC, EA 7294, Centre Européen d'Etude du Diabète, Université de Strasbourg, Fédération de Médecine Translationnelle de Strasbourg, Bld René Leriche, 67200 Strasbourg, France.
authors.forename: N
authors.initials: N
authors.lastname: Jeandidier
authors.affiliation: Institut Galien Paris-Sud UMR CNRS 8612, Université de Paris Sud Faculté de Pharmacie, 92296 Chatenay-Malabry Cedex, France.
authors.forename: C
authors.initials: C
authors.lastname: Vauthier
authors.affiliation: Institut Pluridisciplinaire Hubert Curien (UMR 7178CNRS/CNRS), 74 route du Rhin, 67400 Illkirch, France.
authors.forename: E
authors.initials: E
authors.lastname: Marchioni
authors.affiliation: Institut Charles Sadron (UPR 22CNRS), 23 rue du Loess BP 84047, 67034 Strasbourg Cedex 2, France.
authors.forename: Y
authors.initials: Y
authors.lastname: Frere
authors.affiliation: UMR DIATHEC, EA 7294, Centre Européen d'Etude du Diabète, Université de Strasbourg, Fédération de Médecine Translationnelle de Strasbourg, Bld René Leriche, 67200 Strasbourg, France. Electronic address: s.sigrist@ceed-diabete.org.
authors.forename: S
authors.initials: S
authors.lastname: Sigrist
mesh_terms: D000818:Animals; D001786:Blood Glucose / Q000378:metabolism; D018938:Caco-2 Cells; D002626:Chemistry, Pharmaceutical; D048271:Chitosan / Q000737:chemistry*; D003432:Cross-Linking Reagents; D016503:Drug Delivery Systems; D015195:Drug Design; D004355:Drug Stability; D005079:Excipients; D005612:Freeze Drying; D006801:Humans; D007328:Insulin / Q000008:administration & dosage* / Q000737:chemistry / Q000494:pharmacology; D008297:Male; D009093:Mucus / Q000378:metabolism; D053758:Nanoparticles / Q000737:chemistry*; D051381:Rats; D017208:Rats, Wistar
chemical_list: D001786:Blood Glucose; D003432:Cross-Linking Reagents; D005079:Excipients; D007328:Insulin; D048271:Chitosan
keywords: Chitosan; Complex coacervation; Insulin; Nanoparticles; Oral administration