Non-wettable antibacterial thin film: PS/Aloe vera and PS/Acalypha indica

Abstract

The water and liquid repelling materials due to their low surface energy and specific nanometer and micrometer scale roughness have particular interest due to the great variety of potential applications ranging from self-cleaning surfaces to microfluidic devices. Natural plant-based polymer hydrophobic coatings have several engineering and biomedical applications. In this study, natural plants such as Aloe vera and Acalypha indica were used for preparation of polystyrene hydrophobic film by the dip-coating method. The effects of Aloe vera and Acalypha indica extract on the morphological, structural, optical and antibacterial properties of as-prepared polystyrene thin films were studied. FTIR spectra were carried out to ascertain the presence of functional groups in the prepared polymeric film. Contact angle measurement showed that the PS/ Aloe vera has higher anti-wetting property (CA = 112°) compared to PS/ Acalypha indica (CA = 104°), which could be confirmed by the surface morphology analysis. Furthermore, the effective antibacterial activity against Klebsiella pneumoniae and Staphylococcus aureus was compared by agar-well diffusion method. The observed result reports, PS with Aloe vera film exhibit higher hydrophobic with antibacterial activity compared to PS with Acalypha indica film. In addition, the PS/ Aloe vera coated cotton maintained their repellent properties against various liquids for 10 h, while PS/ Acalypha indica coated cotton exhibit anti-wetting property for 4 h. These findings open up new avenues for the preparation of hydrophobic film for various biomedical applications.