Chitosan Skin Toxicity

Almost all functional properties of chitosan depend on its chain length, charge density, and charge distribution. Numerous studies have demonstrated that the salt form, molecular weight, and degree of deacetylation of chitosan, as well as the pH at which the chitosan is used, influence the functional properties of this polymer (Kean and Thanou, 2010]. 

The chitosan and its derivatives show no acute toxicity and are not absorbed via transdermal route. The European pharmacopoeia contains a single monograph on chitosan hydrochloride. In the United States, chitosan is currently being included in the US Pharmacopoeia [Sarmento and das Neves, 2012]. The chitosan and its derivatives are deemed safe for use as permeation enhancer for transmucosal delivery of hydrophilic drugs and offer promising prospects for novel pharmaceutical applications [Junginger and Verhoef, 1998]. Despite the chitosan and its derivatives interact with lipids and proteins of the membranes of stratum corneum, they may not penetrate into deeper layers of the skin. This can be inferred from the absence of skin irritation by chitosan and its derivatives in Draize test [Aoyagi et al., 1991]. 

Alsarra, I. A. (2009). Chitosan topical gel formulation in the management of burn wounds, Int. 1. Biol Macromol. 45(1), 16-21. 

Agnihotri, S. A., Mallikarjuna, N. N., Aminabhavi, T. M. (2004). Recent advances on chitosan-based micro- and nanoparticles in drug delivery, 100,5-28. 

Mastrobattista, E., Jiskoot, W., Hennink, W. E. (2010). Chitosan-based delivery systems for protein therapeutics and antigens, AdyDrug eJi Rm, 62(1), 59-82. 

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Chitosan acetate and lactate salt films have been tested as wound-healing materials. Mechanical, bioadhesive and biological evaluation of the films were carried out. The results were compared to Omiderm . Chitosan lactate exhibited a lower tensile strength, however, it was more flexible and bioadhesive than chitosan acetate. Chitosan lactate and Omiderm did not cause any allergic reactions in contrast, chitosan acetate produced skin irritation clearly due to the anion. Nevertheless, no sign of toxicity was encountered when the extracts of three preparations were administered parenterally [244]. 

The unique biological properties of chitin and chitosan, including biocompatibility, biodegradability, non-toxicity, antibacterial and hemostatic properties, assure their biochemical significance in skin repair processes. Both biopolymers have an effect on fibroblast (the cells regenerating the extracellular matrix and therefore... 

Chitin and its deacetylated derivative chitosan are suitable bioplatforms that can be further improved by targeted functionalisation for skin repair. For example, the unique biological properties of chitosan characterised with human cell biocompatibility, human serum biodegradability, non-toxicity, antibacterial and haemostatic properties justify the use of this biopolymer in skin repair processes. The haemostatic activity of chitosan is exploited in early treatment of wounds [28], especially in large injuries subjected to heavy bleeding [29]. Many haemostatic products on the market consist thus, fully or partially, of chitosan. Moreover, chitosan aids to a rapid closure of fuU-thickness wounds due to its supportive effect to the fast growing of new blood vessels (angiogenesis) in the injured tissue [30]. Chitin and chitosan can be... 

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