Study of tensiometric properties, microbiological and collagen content in nile tilapia skin submitted to different sterilization methods

Abstract

Tissue bioengineering development is a global concern and different materials are studied and created to be safe, effective and with low cost. Nile Tilapia skin had shown its biological potential as covers for the burn wound. This study evaluates the tilapia skin histological, collagen properties and tensiometric resistance, after treatment by different sterilization methods. Tilapia skin samples were submitted to two sterilization processes: (1) chemical, which consisted in two 2% chlorhexidin baths, followed by sequential baths in increasing glycerol concentrations; and (2) radiation, when glycerolized skin samples were submitted to gamma radiation at 25, 30 and 50 kGy. Microscopic analyzes were performed through Haematoxylin-eosin and Picrosirius Red under polarized light. For tensiometric analysis, traction tests were performed. Glycerol treated skin presented a discrete collagen fibers disorganization within the deep dermis, while irradiated skin did not show any additional change. Throughout the steps of chemical sterilization, there was a higher proportion of collagen with red/yellow birefringence (type I) in the skin samples up to the first bath in chlorhexidin, when compared to samples after the first two glycerol baths (P < 0.005). However, there was no difference in relation to total collagen between groups. In irradiated skin, there was a larger total collagen preservation when using until 30 kGy (P < 0.005). Tensiometric evaluation did not show significant differences in relation to maximum load in the groups studied. We concluded that chemical and radiation (25 and 30 kGy) are efficient methods to sterilize Nile Tilapia skin without altering its microscopic or tensiometric characteristics.

Validation of three different sterilization methods of Tilapia skin dressing: impact on microbiological enumeration and collagen content

“…CHG has been used to disinfect the skin before surgery and sterilize surgical instruments and biological dressings [11,22,24]. In consistent with previous data [11], our results showed that CHG at concentration 4% was effective in the reduction of microbial load of tilapia sh skin in variable degrees and the bactericidal effect increased with increasing contact time.…”

“…CHG has been used to disinfect the skin before surgery and sterilize surgical instruments and biological dressings [11,22,24]. In consistent with previous data [11], our results showed that CHG at concentration 4% was effective in the reduction of microbial load of tilapia sh skin in variable degrees and the bactericidal effect increased with increasing contact time. CHG is a bisbiguanide compound that has a broad spectrum of activity against gram-positive and gram-negative bacteria and fungi, even in the presence of interfering materials, such as blood or serum [19,24].…”

“…The sterilization of wound dressings before use on a patient is critical to guarantee the wellbeing of the patient and the healing process of the skin wound. Ordinary methods used to sterilize skin grafts are ethylene oxide gas sterilization, irradiation, and chemical sterilization [11][12][13]. Ethylene oxide is a toxic gas which likewise generates harmful reaction products with potential hazards to the patient [14,15].…”

“…Chlorhexidine and povidone iodine are routinely used for sterilization and disinfection of grafting procedures as they are effective against Gramnegative, Gram-positive bacteria and fungi and kills by disruption of the cell membrane [11,[19][20][21][22]. In addition, silver nanoparticles have long been known as an antimicrobial agent and are used as silver-containing wound dressings and for disinfection of the wound graft [13,23].…”

Tilapia Fish Skin: a new biological graft in gynecology

“…Fish type I collagen have been considered as an effective material for a biodegradable scaffold or spacer replicating the natural extracellular matrix, which serves to spatially organize cells, 19,20 Additionally, In recent publication of our research group, we found that chemical sterilization as well as radiosterilization at the dosages of 25 kGy and 30 kGy are effective in preparing Nile Tilapia skin for usage as a biological dressing, and these methods do not alter their microscopical nor their tensiometric properties. 21 Another aspect to be considered is the fact that most of the biomaterials available in our country, and all developed world, as wound dressings are imported and come at very high cost. Dornellas et al 22 had evaluate the histological, anatomical and functional agenesis in our country.…”