1 INTRODUCTION
National Pressure Ulcer Advisory Panel (NPUAP) defined pressure ulcers
as locally damaged soft tissue or skin over a bony part or due to a
device (Unver et al., 2017). In the United States, pressure ulcers have
affected about 2.5 million patients annually and the treatments are
estimated to cost between 9 and 11.5 billion dollars. Due to a direct
result of pressure ulcers, about 60,000 patients died annually (Zapirain
et al., 2017). Pressure ulcers are often associated with disabilities
where 70% of the time occurring in people above 70 years old. Prolonged
periods of recovery are due to chronic deep wounds suffered by several
elderly patients. The mortality rate of patients who suffered from
serious infective complications such as bacteremia was reported to be
greater than 50%. Even though preventable, pressure ulcer is a common
find in bed-ridden, elderly patients who are immobilized by their acute
illness. The percentage is foretold to be more than 11% of the
population by 2020 (Khor et al., 2014). As the skin damages, it loses
its functions such as preventing water vapor loss, physical protection
and thermal regulators. In this situation, wound infection is better
prevented by declining bacterial entry into the open wound rather.
The microorganisms recurrently found in colonized pressure ulcers areStaphylococcus aureus and Gram-negative bacilli such as
Enterobacteriaceae, Acinetobacter baumannii and Pseudomonas
aeruginosa . The patients possessing colonized ulcers with developing
infections are often seriously ill (Braga et al., 2013). Consequently,
this leads to prolonged hospital stays and the need to use invasive
medical devices such as central vascular catheter, tracheal tube and
urinary catheter.To tackle the issue, a range of wound dressing products
were created in order to return the functions to damaged skin (Vowden &
Vowden, 2017). Unfortunately, these wound dressings come with their fair
share of drawbacks. Silver wound dressings have been reported to cause
argyria from extensive use of silver-containing wound dressing materials
and medications (Berger et al., 2013). In addition to anti-inflammatory
effects, nanosilver has been shown to control collagen deposition
leading to a proper alignment of collagen fibrils that accelerates wound
healing and have shown their efficacy in bypassing drug-resistance
mechanisms (Song et al., 2015).
In wound healing, the wound dressing acts as a protection to the wound
while the dermal and epidermal tissues heal. Thus, natural polymers such
as polysaccharides; chitosan, alginates, heparin, and cellulose are
widely selected in wound treatments and management because they are
biologically compatible, biodegradable and similar to macromolecules
that are familiar to the human body (Capanema et al., 2017).
Phomopsidione (C7H10O4)
is a novel ketone derivative isolated from Diaporthe flaxiniiED2. In this study, we designed a chitosan-polyethylene glycol (PEG)
nanocomposite wound dressing hydrogel using phomopsidione as
antimicrobial finishing. The mechanical and physical properties of the
developed hydrogel were characterized and in vitro antimicrobial
efficiency of the hydrogel was evaluated on the clinical wound
microorganisms.