Fabrication of superoleophobic cotton fabric for multi-purpose applications

Antimicrobial Properties of Plant Fibers

Healthcare-associated infections (HAI), or nosocomial infections, are a global health and economic problem in developed and developing countries, particularly for immunocompromised patients in their intensive care units (ICUs) and surgical site hospital areas. Recurrent pathogens in HAIs prevail over antibiotic-resistant bacteria, such as methicillin-resistant Staphylococcus aureus (MRSA) and Pseudomonas aeruginosa. For this reason, natural antibacterial mechanisms are a viable alternative for HAI treatment. Natural fibers can inhibit bacterial growth, which can be considered a great advantage in these applications. Moreover, these fibers have been reported to be biocompatible and biodegradable, essential features for biomedical materials to avoid complications due to infections and significant immune responses. Consequently, tissue engineering, medical textiles, orthopedics, and dental implants, as well as cosmetics, are fields currently expanding the use of plant fibers. In this review, we will discuss the source of natural fibers with antimicrobial properties, antimicrobial mechanisms, and their biomedical applications.

Multifunctional coating of cotton fabric via the assembly of amino-quinone networks with polyamine biomacromolecules and dopamine quinone

Functional textiles with antibacterial properties and UV protection are essential for human health. However, the process of functional modification of textiles is usually done with the help of chemical cross-linking agents to improve the bonding fastness of functional finishing agents on textiles. The use of chemical cross-linking agents is not eco-friendly enough and is prone to chemical waste. In this study, some highly reactive polyamine biomolecules were combined with dopamine quinone, a super adhesive bionic material, to spontaneously construct amino-quinone networks (AQNs) coatings on the surface of cotton fabrics without the addition of chemical crosslinkers. The amino/quinone compounds (A/Q) self-crosslinking reaction is achieved by Michael addition and Schiff base reaction between the quinone group in dopamine quinone and the amino group in chitosan (CTS), chitooligosaccharide (COS) or ԑ-polylysine (ԑ-PL). The combination of polyamines and dopamine quinone during the cotton finishing process imparts antibacterial and UV protection to cotton fabric. The results showed that the AQNs coating modified fabrics had superb UV protection and antibacterial rates of over 96% against both E. coli and S. aureus. In addition, the AQNs coating modified fabrics had good resistance to washing and mechanical abrasion. This study proposes that self-assembled amino-quinone network multifunctional coatings of dopamine quinone and polyamine biomolecules are of guiding significance for the development of environmentally friendly bio-based materials.

Surface Modification of Cotton Fabric Using TiO2 Nanoparticles for Self-Cleaning, Oil-Water Separation, Antistain, Anti-Water Absorption, and Antibacterial Properties

Superhydrophobicity is of interest for practical applications such as water repellency, self-cleaning, stain resistance, antibacterial properties, and oil-water separation. In this work, a superhydrophobic coating on cotton fabric is prepared by simple immersion in TiO₂ nanoparticles and perfluorodecyltriethoxysilane solution. Its antiwetting properties, surface morphology, and functionality are characterized. The cotton fabric shows superhydrophobicity with a water static contact angle of 169.3 ± 2.1° and tilt angle of 6.3 ± 2.0°. The coating is also characterized by performing stability tests, and it shows excellent mechanical durability, chemical stability, and thermal stability. Additionally, the water droplet dynamic on the coated surface is also studied. The coated cotton fabric exhibits excellent self-cleaning, stain resistance, rust stain resistance, anti-water absorption, and antibacterial properties. It can also be used in oil-water separation with a high separation efficiency and excellent reusability.

Bioinspired oil-water separation approaches for oil spill clean-up and water purification

Water contamination is one of the major environmental and natural resource concerns in the twenty-first century. Oil contamination can occur during operation of machinery, oil exploration and transportation, and due to operating environment. Oil spills occasionally occur during oil exploration and transportation. Water contamination with various chemicals is a major concern with growing population and unsafe industrial practices of waste disposal. Commonly used oil-water separation techniques are either time consuming, energy intensive and/or environmentally unfriendly. Bioinspired superhydrophobic/superoleophobic and superoleophobic/superhydrophilic surfaces have been developed which are sustainable and environmentally friendly. Bioinspired oil-water separation techniques can be used to remove oil contaminants from both immiscible oil-water mixtures and oil-water emulsions. Coated porous surfaces with an affinity to water and repellency to oil and vice versa are commonly used. The former combination of affinity to water and repellency to oil is preferred to avoid oil contamination of the porous substrate. Oil-water emulsions require porous materials with a fine pore size. Recommended porous materials include steel mesh and cotton fabric for immiscible oil-water mixtures and cotton for oil-water emulsions. A review of various approaches is presented in this paper. This article is part of the theme issue 'Bioinspired materials and surfaces for green science and technology (part 2)'.