Since plastics industrial production, features such as cost, convenience, safety, and the low cost came up as significant benefits. Further to the benefits added the aesthetic qualities, the mechanical strength and the capability to mix with other materials such as fibres. All these contributed to the rapid expansion of plastics (polystyrene and nylon) in multiple applications and various purposes, such as biomedical materials, packaging, transport, industry, and agriculture. On the other hand, global warming is now one of the most concerning issues for all cultures worldwide [1]. It is considered that replacing some of the conventional materials in various applications such as wound dressings with biodegradable starch-based films is a step forward in addressing the environmental issues [2]. Due to mechanical debriding of tissues, traditional dressings like gauges are counterproductive and end up causing painful wound trauma during dressing procedures. The development of transparent wound dressing films enables a moist healing environment with enhanced bacterial impermeability [3].

The performance of polyvinyl alcohol/starch/citric acid (PVA/St/CA) based composite film for wound dressing applications is addressed in this work. Literature recorded fixed composition of PVA (2.5 w/w%), starch (2.5 w/w%), and glycerol (2 w/w%) during 70-80^oC casting temperature were implemented. Different citric acid concentrations (0.5 to 2g) were investigated during the development of composite film solution casting [4]. Prepared samples have been characterized by swelling index [5], solubility dependent biodegradability [6], tensile strength (TS) [7]. The film also exhibits enhanced combinations of the water vapour transmission rate and antibacterial efficiency against the bacterial flora (various bacteria existent in the air). As an extra benefit, such materials are easily degraded in water for up to seven days with a minute footprint. A potential candidate for wound dressing applications has been inferred from the biodegradable PVA/St/CA films with all these useful features.

References:

1. Jeong, H., et al., Novel Eco‐Friendly Starch Paper for Use in Flexible, Transparent, and Disposable Organic Electronics. Advanced Functional Materials, 2018. 28(3): p. 1704433.
2. Kamoun, E.A., E.-R.S. Kenawy, and X. Chen, A review on polymeric hydrogel membranes for wound dressing applications: PVA-based hydrogel dressings. Journal of advanced research, 2017. 8(3): p. 217-233.
3. Das, A., et al., Optimality of poly-vinyl alcohol/starch/glycerol/citric acid in wound dressing applicable composite films. International Journal of Biological Macromolecules, 2020.
4. Yoon, S.D., S.H. Chough, and H.R. Park, Properties of starch‐based blend films using citric acid as additive. II. Journal of Applied Polymer Science, 2006. 100(3): p. 2554-2560.
5. Das, A., R. Uppaluri, and C. Das, Compositional synergy of poly-vinyl alcohol, starch, glycerol and citric acid concentrations during wound dressing films fabrication. International Journal of Biological Macromolecules, 2020. 146: p. 70-79.
6. Boonsuk, P., et al., Modified cassava starch/poly (vinyl alcohol) blend films plasticized by glycerol: Structure and properties. Journal of Applied Polymer Science, 2020. 137(26): p. 48848.
7. Hassan, A., et al., Development of anti-bacterial PVA/starch based hydrogel membrane for wound dressing. Journal of Polymers and the Environment, 2018. 26(1): p. 235-243.