Novel antimicrobial finishing of organic cotton fabrics using nano-emulsions derived from Karanja and Gokhru plants

Plant-based antimicrobial finishing of textiles is comparable in efficacy, can replace synthetic antimicrobial agents, and is environmentally safe and effective. However, developing durable antimicrobial finishes on cotton-based textiles is a challenge. This research reports the development and characterization of nano-emulsions obtained from Karanja [Milletia pinnata] and Gokhru [Pedalium murex Linn] plants. The nano-emulsions were produced using Milletia pinnata, coconut oil, and curry leaves (nano-emulsion 1) and Pedalium murex, coconut oil, and curry leaves (nano-emulsion 2). The nano-emulsions were characterized for their thermal stability, particle size, pH, and percentage add-on. Two different oils, with surfactant (polysorbate) ratios [1:1 and 1:2], were finished on organic cotton fabrics using a batch process. Scanning electron microscopy images were evaluated to determine the surface morphology of the finished fabrics, and gas chromatography-mass spectrometry images of nano-emulsions were studied to determine the specific chemical constituents of nano-emulsions 1 and 2. The finished fabrics were evaluated for their antimicrobial resistance using various gram-positive bacteria [Staphylococcus aureus, Staphylococcus epidermidis], which are found on human skin and cause nosocomial infections, gram-negative bacteria [Escherichia coli and Klebsiella pneumoniae], which cause urinary tract infections, and fungi [Aspergillus niger]. The antimicrobial resistance was in the range of 98.62-99.87%, even after 10 washes, indicating that the finishes were effective and durable. The finished and unfinished fabrics were also evaluated for their performance properties, tensile strength, and moisture vapor transmission rate, and the results indicated good durability and comfort characteristics. Our findings highlight the potential of plant-based antimicrobial agents for durable finishing of cotton textiles with antimicrobial properties, thus preventing the spread of infections.