title: Gelatin-based nanoparticles as DNA delivery systems: Synthesis, physicochemical and biocompatible characterization.
abstract: The rapidly rising demand for therapeutic grade DNA molecules requires associated improvements in encapsulation and delivery technologies. One of the challenges for the efficient intracellular delivery of therapeutic biomolecules after their cell internalization by endocytosis is to manipulate the non-productive trafficking from endosomes to lysosomes, where degradation may occur. The combination of the endosomal acidity with the endosomolytic capability of the nanocarrier can increase the intracellular delivery of many drugs, genes and proteins, which, therefore, might enhance their therapeutic efficacy. Among the suitable compounds, the gelification properties of gelatin as well as the strong dependence of gelatin ionization with pH makes this compound an interesting candidate to be used to the effective intracellular delivery of active biomacromolecules. In the present work, gelatin (either high or low gel strength) and protamine sulfate has been selected to form particles by interaction of oppositely charged compounds. Particles in the absence of DNA (binary system) and in the presence of DNA (ternary system) have been prepared. The physicochemical characterization (particle size, polydispersity index and degree of DNA entrapment) have been evaluated. Cytotoxicity experiments have shown that the isolated systems and the resulting gelatin-based nanoparticles are essentially non-toxic. The pH-dependent hemolysis assay and the response of the nanoparticles co-incubated in buffers at defined pHs that mimic extracellular, early endosomal and late endo-lysosomal environments demonstrated that the nanoparticles tend to destabilize and DNA can be successfully released. It was found that, in addition to the imposed compositions, the gel strength of gelatin is a controlling parameter of the final properties of these nanoparticles. The results indicate that these gelatin-based nanoparticles have excellent properties as highly potent and non-toxic intracellular delivery systems, rendering them promising DNA vehicles to be used as non-viral gene delivery systems.
authors.affiliation: Departament de Fisiologia - Facultat de Farmàcia, Universitat de Barcelona, Avda. Joan XXIII s/n, 08028 Barcelona, Spain; Institut de Nanociència i Nanotecnologia - IN(2)UB, Universitat de Barcelona, Avda. Joan XXIII s/n, 08028 Barcelona, Spain. Electronic address: mcmoranb@ub.edu.
authors.forename: M C
authors.initials: MC
authors.lastname: Morán
authors.affiliation: Departament de Fisiologia - Facultat de Farmàcia, Universitat de Barcelona, Avda. Joan XXIII s/n, 08028 Barcelona, Spain.
authors.forename: N
authors.initials: N
authors.lastname: Rosell
authors.affiliation: Departament de Fisiologia - Facultat de Farmàcia, Universitat de Barcelona, Avda. Joan XXIII s/n, 08028 Barcelona, Spain.
authors.forename: G
authors.initials: G
authors.lastname: Ruano
authors.affiliation: Institut de Nanociència i Nanotecnologia - IN(2)UB, Universitat de Barcelona, Avda. Joan XXIII s/n, 08028 Barcelona, Spain; Departament de Fisicoquímica - Facultat de Farmàcia, Universitat de Barcelona, Avda. Joan XXIII s/n, 08028 Barcelona, Spain.
authors.forename: M A
authors.initials: MA
authors.lastname: Busquets
authors.affiliation: Departament de Fisiologia - Facultat de Farmàcia, Universitat de Barcelona, Avda. Joan XXIII s/n, 08028 Barcelona, Spain; Institut de Nanociència i Nanotecnologia - IN(2)UB, Universitat de Barcelona, Avda. Joan XXIII s/n, 08028 Barcelona, Spain.
authors.forename: M P
authors.initials: MP
authors.lastname: Vinardell
mesh_terms: D016475:3T3 Cells; D000818:Animals; D001672:Biocompatible Materials; D004247:DNA / Q000008:administration & dosage*; D004337:Drug Carriers; D005780:Gelatin / Q000737:chemistry*; D006367:HeLa Cells; D006461:Hemolysis; D006801:Humans; D051379:Mice; D053758:Nanoparticles / Q000737:chemistry*; D011479:Protamines / Q000737:chemistry; D051381:Rats
chemical_list: D001672:Biocompatible Materials; D004337:Drug Carriers; D011479:Protamines; D005780:Gelatin; D004247:DNA
keywords: DNA; DNA entrapment; Endosomolytic escape; Haemolyisis; In vitro cytotoxicity; Nanoparticles