Study on the debridement efficacy of formulated enzymatic wound debriding agents by in vitro assessment using artificial wound eschar and by an in vivo pig model

Abstract

An in vitro efficacy study using newly developed artificial wound eschar (AWE) substrate was conducted for assessing enzyme dose response. The AWE substrate is prepared by the enzymatic conversion of fibrinogen to fibrin in the presence of collagen, fibrin, and elastin to form an insoluble planar matrix. AWE substrate was placed on Franz Diffusion Cells for continuously monitoring the debridement progress. A parallel in vivo study was performed using pig thermal-burn wounds. Papain at concentrations of 200, 400, 800, and 1,600 U/mg was used as the model debriding enzyme for both studies. The data from the first 5 hours of the in vitro testing showed that debriding activity increased as the enzyme concentration increased. The histological results of the in vivo biopsy samples showed that enzyme doses above 800 and 1,600 U/mg successfully achieved debridement on day 8, while lower treatment groups still contained eschar tissue. Using the histological measurement results (wound depth score) a dose response that correlated to the in vitro assessment was found. Granulation tissue maturity and reepithelialization displayed correlation with the enzyme dose. Results indicate that AWE substrate can be used to predict debridement efficacy in vitro when correlation to the in vivo assessment is achieved.

The Effect of Various Wound Dressings on the Activity of Debriding Enzymes

“…Collagen-FITC, elastin-rhodamine, and fibrin-coumarin were the raw materials used for producing the AWE substrate. 21 To prepare 1 g of AWE substrate, 650 mg collagen-FITC and 100 mg each of elastin-rhodamine and fibrin-coumarin were weighed into a 50 mL-tube and homogenized in 10 mL of TBS. In a separate tube, 10 mL of fibrinogen solution was prepared at 15 mg/mL with TBS.…”

Emerging topics in cutaneous wound repair

“…A number of different modalities exist for wound debridement. The four most common debridement methods are surgical, autolytic, enzymatic, and mechanical 32 …”

“…The four most common debridement methods are surgical, autolytic, enzymatic, and mechanical. 32 Wound care 33 In order to prevent tissue dehydration and cell death and to enhance neo-angiogenesis and reepithelialization, the use of a clean, moist wound-healing environment appears to be very useful. 34 Recent advancements in technology and in the understanding of human physiology have led to the commercial development of dressings that offer material improvements with regard to these same ancient fundamental principles.…”

A comparative study on the cellular viability and debridement efficiency of antimicrobial‐based wound dressings

“…One of the most important prerequisites in chronic wound healing is to remove eschar and slough, which helps to clean the wound bed . To encourage wound healing in chronic wounds, advanced wound dressings should have the ability to aid in the breakdown and removal of eschar (debridement) and slough (desloughing) to enhance antimicrobial and antibiofilm ability and help to clean the wound bed between dressing changes .…”