Preparation and activity of nanocellulosic materials as protease sensors and sequestrants

Authors: Edwards, Judson - Vince; Prevost, Nicolette; Fontenot, Krystal; Condon, Brian

Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 1/16/2018
Publication Date: N/A
Citation: N/A

Interpretive Summary:

Technical Abstract: Chronic wounds are a major clinical problem with an estimated 40 million people suffering from them worldwide, and one of the most costly healthcare problems today. ‘Intelligent’ dressings may be defined as materials that respond to specific changes in the wound environment to bring about a useful result. Considerable promise in the application of nanocellulosic hydrogels, aerogels, and nanocomposites as dressings has been demonstrated due to favorable properties that promote optimal moisture conditions. Here we present a series of modified nanocellulosic and cellulosic materials designed to remove harmful proteases from a chronic wound while detecting protease levels. Methods: The biosensors were prepared by a method previously report (Edwards’s et al. J. Biomat. Appl., 2017). To start the sensor/protease reaction 50 µL of human neutrophil elastase at various concentrations ranging from 2-0.015 U/mL were utilized. Material protease sequestration evaluation was performed in a like manner using a 96-well format by incubating 2 milligrams of material in a protease solution for 1 hour. Results: A correlation between zeta potential values and the degree of protease sequestration imply that the greater the negative surface charge of the nanomaterials, the greater the sequestration of positively charged neutrophil proteases. The biosensors gave detection sensitivities of 0.015-0.13 units/ml, which are at detectable human neutrophil elastase levels present in chronic wound fluid. Conclusion: The sensor portion is a fluorescent peptide-cellulose conjugate interchangeable on the surface of different semi-occlusive dressing motifs and sensitive to protease levels found in chronic wounds. The protease modulation portion is based on the degree of surface zeta potential required on the material surface to remove excess wound protease levels. The physical and interactive biochemical properties of the nano-based biosensors are suitable for interfacing with protease sequestrant prototype wound dressings. A discussion of the relevance of protease sensors and cellulose nanomaterials to current chronic wound dressing design a