Antimicrobial treatment of wounds and schars using immobilized keratinase and enrofloxacin loaded on pva-pectin cryogel films

MARTINAZ, YANINA; CAVELLO, IVANA; HOURS, ROQUE ALBERTO; CAVALITTO, SEBASTIÁN FERNANDO; CASTRO, GUILLERMO

Taipei

Congreso; The 5th International Conference on Industrial Bioprocesses. IFIB-2012; 2012

Efficient topic treatment of ulcerating wounds and eschar infections is of high interest for patient's fast healing, especially in chronic pathologies like diabetes. A film containing antibiotics and enzymes for eschar and burn debridement in replacement of surgical removal of necrotic tissue is an interesting alternative in health care procedures.A keratinase isolated from non-pathogen fungi Paecilomyces lilacinus (LPS #876) was tested against proteins present in the skin such as albumin, collagen, elastin and keratin. The enzyme was able to act on all assayed substrates but collagen was hydrolyzed faster.Keratinase was physically immobilized onto PVA-pectin cryogels. The keratinase release was 20.8±2.1, 63.8±0.2, 41.5±3.5 and 26.0±3.5 % in cryogels containing pectins with esterification degrees (DE) 33.0, 55.0, 62.7 and 71.7 % respectively at 37 ºC after 3 hours incubation. In presence of 0.75M NaCl, the percentage of enzyme release increased to: 57.5±1.5, 65.8±3.8, 57.3±0.2 and 34.0±4.0 for the four pectins respectively. The presence of enrofloxacin in the cryogels did not affect the enzyme activity.In-vitro studies of enrofloxacin release from PVA-pectin cryogels at pH close to the human skin (pH= 5.5) showed 15.0% free antibiotic following first order kinetic at 37ºC after 5 h incubation. However, in the presence of keratinase only 6.0% of enrofloxacin was released under the same experimental conditions.The system developed in the present work shows potential use as a medical device for wound healing because it combines keratinase activity to remove necrosed tissue and cell debridement with the antimicrobial activity of enrofloxacin, which can be modulated also by salt gradient, concentration and esterification degree of pectins.