title: "The Good, the Bad and the Ugly" of Chitosans.
abstract: The objective of this paper is to emphasize the fact that while consistent interest has been paid to the industrial use of chitosan, minor attention has been devoted to spread the knowledge of a good characterization of its physico-chemical properties. Therefore, the paper attempts to critically comment on the conflicting experimental results, highlighting the facts, the myths and the controversies. The goal is to indicate how to take advantage of chitosan versatility, to learn how to manage its variability and show how to properly tackle some unexpected undesirable features. In the sections of the paper various issues that relate chitosan properties to some basic features and to advanced solutions and applications are presented. The introduction outlines some historical pioneering works, where the chemistry of chitosan was originally explored. Thereafter, particular reference is made to analytical purity, characterization and chain modifications. The macromolecular characterization is mostly related to molecular weight and to degree of acetylation, but also refers to the conformational and rheological properties and solution stability. Then, the antimicrobial activity of chitosan in relation with its solubility is reviewed. A section is dedicated to the formulation of chitosan biomaterials, from gel to nanobeads, exploring their innovative application as active carrier nanoparticles. Finally, the toxicity issue of chitosan as a polymer and as a constructed nanomaterial is briefly commented in the conclusions.
authors.affiliation: Laboratory of Physical and Macromolecular Chemistry, Department of Chemical and Pharmaceutical Sciences, University of Trieste, Via Giorgieri 1, 34127 Trieste, Italy. bbellich@units.it.
authors.forename: Barbara
authors.initials: B
authors.lastname: Bellich
authors.affiliation: Department of Life Sciences, University of Trieste, Via Giorgieri 1, 34127 Trieste, Italy. ilenia.d'agostino@phd.units.it.
authors.forename: Ilenia
authors.initials: I
authors.lastname: D'Agostino
authors.affiliation: Department of Life Sciences, University of Trieste, Via Giorgieri 1, 34127 Trieste, Italy. ssemeraro@units.it.
authors.forename: Sabrina
authors.initials: S
authors.lastname: Semeraro
authors.affiliation: Laboratory of Physical and Macromolecular Chemistry, Department of Chemical and Pharmaceutical Sciences, University of Trieste, Via Giorgieri 1, 34127 Trieste, Italy. gamini@units.it.
authors.forename: Amelia
authors.initials: A
authors.lastname: Gamini
authors.affiliation: Laboratory of Physical and Macromolecular Chemistry, Department of Chemical and Pharmaceutical Sciences, University of Trieste, Via Giorgieri 1, 34127 Trieste, Italy. cesaro@units.it.|Elettra-Sincrotrone Trieste, Strada Statale 14 km 163.5, Area Science Park, 34149 Trieste, Italy. cesaro@units.it.
authors.forename: Attilio
authors.initials: A
authors.lastname: Cesàro
mesh_terms: D000107:Acetylation; D001672:Biocompatible Materials / Q000737:chemistry; D048271:Chitosan / Q000737:chemistry*; D006801:Humans; D008970:Molecular Weight; D053758:Nanoparticles / Q000737:chemistry; D011108:Polymers / Q000737:chemistry; D012995:Solubility; D012996:Solutions / Q000737:chemistry
chemical_list: D001672:Biocompatible Materials; D011108:Polymers; D012996:Solutions; D048271:Chitosan
keywords: antimicrobial activity; chitosan; conformation; degree of acetylation; drug delivery; from gel to nanobeads; molecular weight; physico-chemical properties