Development of a microbial coating for cellulosic surface using aloe vera and silane

Abstract

The highly contagious nature of SARS-CoV-2 (COVID-19) virus has created a havoc effect all over the world in a very short period. The most effective method for precaution of this virus as suggested by WHO is use of PPEs (triple layered face mask, body suits) and social distancing. However, the frontline doctors and medical staff have high risk of exposure to the virus during treatments and removal and discarding of the PPEs. Also the PPEs are of the onetime use and wearing these PPEs in hot and humid seasons is very uncomfortable. A possible solution of this problem is if clothes are anti-bacterial and anti-viral in nature, one single-layered will be sufficient and the spread of virus will also be minimized. Considering this, we have designed a facile and durable anti-wash antimicrobial coating on cloth by aloe vera and hexadecyltrimethoxysilane (HDTMS). In lab scale study, present coating shows good chemical and thermal stability making it reusable multiple times even after repeated washing. The coated cloth reveals the excellent anti-dirt and stain resistance properties leading to complete non-adherence of dirt and stain (e.g. Color, food, ink) on it. Anti-bacterial and anti-fungi properties of the coated cloth were confirmed by doing E. coli (bacteria) and A. Niger (fungus) culture studies, respectively. This coating is imbibed with well-known anti-viral agent aloe vera which inhibits the attachment of the virus on the surface. The water-repellent nature of the coating combined with the use anti-viral agent, aloe vera makes it a potential anti-COVID-19 coating.

Nano Coating of Aloe-Gel Incorporation Additives to Maintain the Quality of Freshly Cut Fruits

“…Furthermore, it aims to provide a modified atmosphere, time transfer inhibitors, reduce moisture and aroma loss, delay discoloration, and improve appearance (Chauhan and Kumar, 2020;Ochoa-Velasco et al, 2021). Another advantage of the edible coating is the reduction of synthetic packing waste because this layer consists of biodegradable raw materials (Yousuf and Qadri, 2020;Le et al, 2021).…”

“…Aloe gel tends to reduce the rate of respiration, ethylene production, heavy shrinking, and softening. It can be used to extend the shelf life after harvest and maintain the product's sensory capabilities during the storage period (Chauhan and Kumar, 2020;Ehtesham Nia et al, 2021;Hasan et al, 2021).…”

“…Aloe-gels have the advantages of being biodegradable, permeable to oxygen, antioxidant power, and low toxicity effects (Chauhan and Kumar, 2020;Sánchez et al, 2020;Sonawane et al, 2021). However, in some cases, the edible coating does not maximize its role in maintaining quality and extending the shelf life of the fruit.…”

Advances in the Prophylaxis of Respiratory Infections by the Nasal and the Oromucosal Route: Relevance to the Fight with the SARS-CoV-2 Pandemic

“…The latest studies and reviews focus the attention on S-containing polysaccharides ( Chitosan [ 146 ] and semisynthetic derivatives [ 147 ], kappa-, iota-, lambda- Carrageenan [ 148 , 149 , 150 ], Fucoidan [ 150 , 151 , 152 ]), Lactoferrin [ 153 , 154 ], Aloe vera polysaccharides [ 155 ], the flavonoids Hesperidin [ 14 , 156 , 157 ], Hispidulin [ 158 ], Quercetin [ 153 ], Rutin [ 159 ], Resveratrol [ 160 ], the saponin Glycyrrhizin [ 161 ], and the diterpenoid Andrographolide [ 162 , 163 ]. Many of them possess not only the ability to block the adhesin–receptor connection and following viral entry, but are also proven to exhibit antiviral activity due to inhibition of viral replication ( Chitosan and other sulfated polysaccharides [ 145 , 164 , 165 ], Resveratrol [ 166 , 167 ], Aloe vera polysaccharides [ 155 ], Glycyrrhizin [ 168 ], Andrographolide [ 169 ]), inhibition of protein synthesis ( Aloe vera polysaccharides [ 155 ] and Andrographolide [ 169 ]), blocking the viral release and spread ( Andrographolide [ 169 ]), and/or immunomodulatory properties ( Chitosan [ 170 ]). The antiviral potency of other biomolecules is primarily due to interference in one or multiple steps of the infectious cycle of pathogens (i.e., after adhesion) and by activating the host immunomodulatory system.…”

Antiviral Coatings as Continuously Active Disinfectants

“…The antiviral actives include biopolymers (e.g., antimicrobial peptides), synthetic polymers (e.g., polyethyleneimines, and graphene [14,44,45]. Natural product-based surface coatings and super-hydrophobic surfaces are also under development [46,47]. Although many of these innovative technologies demonstrate promising antiviral effectiveness, further assessments of efficacy against additional types of viruses under various conditions are required.…”