An interesting study was done by the European Center for Disease Prevention and Control1, revealed that more than 4 million people acquire a Healthcare-Associated Infection (HCAI) each year, which results in 37,000 deaths. These infections are majorly due to transmission from the contaminated surfaces. Therefore, there is an increase in the need to protect surfaces, from germs and microbes. This is not only limited to the healthcare sector but also in general use.
Today, COVID-19 has drastically changed the perception of hygiene and cleanliness, people have started paying close attention to cleanliness and hygiene.
The best way to prevent microbial infection is to maintain good hygiene of our own self, keep our surroundings clean & protect surfaces by use of anti-microbial products.
History of Antimicrobials
Anti-microbials are the substances which are used to destroy or inhibit the growth of microorganisms, including Bacteria, Virus & Fungi. Ayurved, which is more than 5000 year old manuscript from ancient India, has documented use of Silver as an anti-microbial substance. This is the oldest known reference of any natural element to be anti-microbial.
The discovery of the first synthetic anti-microbial agent was approximately four decades ago, which is a major milestone in the history of medicine and human health. The first synthetic anti-microbial agent in the world was Salvarsan2, a remedy for Syphilis that was synthesized by Ehrlich.
For decades, various anti-microbial agents viz. Triclosan, Chlorine, Bromine, Chitosan, Silver, Copper, Zinc etc. have been used by scientists and technologies as anti-microbial agents but each active ingredient has its own limitations and benefits. Most of them are reported to produce harmful effects on the human immune system. However, Silver is known to be a very broad spectrum anti-microbial and found to be the safest among all other alternatives.
Metal ions have been used for their anti-microbial properties for years in various applications. Among the different metal ions, Silver-based antimicrobials are expected to be the largest market for anti-microbial applications. The dominant market position of the Silver segment can be attributed due to its high efficacy, long lasting effect & durability.
Nichem’s Silver based/powered Antimicrobials Technology
At NICHEM we have successfully developed and commercialized Silver based anti-microbials under our brand – MICROFIGHT. The development started with converting elemental Silver into the best suited form for various applications viz. Plastics, Coatings, Textiles etc. Our research on Silver as anti-microbial is based on various combinations of Silver on inorganic molecules likes Calcium Carbonate, Silica, Titanium Dioxide etc. We have also explored Silver combinations with other anti-microbial actives like Copper, Zinc etc. to create niche products that give enhanced biostatic & biocidal activity at very low concentrations. These combinations impart excellent microbe controlling properties against virus, bacteria, fungi & algae.
Mechanism of Action of Silver
The antimicrobial properties of Silver have been known for centuries. Owing to electrostatic attraction and affinity to Sulphur proteins, Silver ions adhere to cell wall & cytoplasmic membrane. The adhered ions enhance the permeability of cytoplasmic membrane & lead to disruption of the bacterial envelope. After the uptake of Silver ions into the cell, the respiratory enzymes are deactivated, The interaction of Silver ions with Sulphur & phosphorous of DNA cause problems in DNA replication, cell production or even result in termination of microorganisms5.
Figure 1. Silver Mechanism of Action
Apart from being a broad spectrum anti-microbial, one of the most unique property of Silver is to offer residual protection of minimum 12 hours to 90 days depending on the application. This is not given by any other active and hence is a value proposition of NICHEM products.
Nichem’s Research on Silver
1. Ganga Research Summary
Figure 2. Dissolved Silver Conc.in Ganga River
We know since ages that the water of our holy River Ganga is considered as very pure. It is preserved in Indian households for 25-30 years without any bacteria or algal growth. This has been a great puzzle to the scientists & various theories have been proposed. Nichem conducted a preliminary research of the Ganga water to note some interesting findings about the water, sand & sludge of the river. The factor ‘X’ of Ganga water is Silver ions at a concentration of 55 to 60 ppb.
This makes the water pure & disease resistant. Ganga water is not bacteria free, but it is free of pathogenic (disease causing) bacteria. Silver is indestructible since it is an element. Thus, it is available to treat any fresh contamination after the host has expired. We have found that the sludge of Ganga River contains 250 ppm of Silver which is very high. The sand consists of about 0.46-8 mg per kg of Silver. The water consists of about 60 ppb of Silver (Fig.3).
2. MicroFight Research Summary
Figure 3 MicroFight Performance on Plastic
At NICHEM, we have developed various grades of MicroFight to offer antibacterial, antiviral, antifungal & antialgal activity depending on the application requirement.
Fig 4 depicts the performance of various MicroFight grades offered by NICHEM for imparting anti-microbial protection on the surface of polymers. Today, we export a sizable quantity of this product worldwide.
During the pandemic we explored the combination of Silver with Titanium Dioxide (Silver Titanate) for drinking water purification, textile & paper application. It works on the concept of destroying the virus & bacteria by redox potential action.
Major application of this combination is in the coating of the water tank to protect them from bacterial & algal attack. This unique technology of active Silver of Titanium Dioxide keeps the water fresh, clean & free from harmful microbes at all times. This technology provides round the clock protection as the surface does not allow any bio-film to develop. Thus, the water remains free from all types of harmful biological contamination.
In textiles, we created & distributed innumerable masks based on this technology to Mumbai Police, Health care workers. These masks are tested for antiviral, antibacterial activity for up to 75 washes & are very comfortable to reuse. This property can be extended to any cotton or synthetic fabrics like hospital linen, hotel linen, railway linen, innerwear, sportswear, sanitary wear & regular clothing.
We were also successful in imparting antiviral antibacterial activity on paper for stationery use.
Fig 5 & 6 Depicts the Efficacy of MicroFight for Textiles & Paper Applications.
Figure 4. MicroFight Efficacy on Paper
Figure 5. MicroFight Efficacy on Mask
One of our victorious combination is Silver with Hydrogen Peroxide. This synergistic combination of Silver with Hydrogen Peroxide provides high efficacy in against microorganisms in all possible media like air, surface, soil, water etc. It enhances the performance of plain Hydrogen Peroxide by almost 20 times making it more powerful to give instant destruction of the microbiological species.
Silver synergized Hydrogen Peroxide is widely used in hospitals for sanitation. This synergistic combination is tested for its efficacy from external laboratories. It was tested against TB bacteria by BARC, Mumbai and also tested by Haffkine Institute of Training, Research & Testing, Mumbai for its H1N1 activity against virus. This combination shows excellent efficacy in surface and air disinfection, especially in the operation theaters.
Applications based on Silver Antimicrobials
Silver promises to offer a good potential for the future anti-microbial. Our MicroFight range with various Silver Technologies can be widely used in various applications namely Plastics, Textiles, Surfaces, Air, Paints, Coatings, Water Purification Media, Agriculture, Cosmetics & Pharmaceuticals to treat wounds, burns, acne, dandruff thereby healing multiple infections.
At NICHEM, we will continue with our research to explore more & more applications using Silver for the benefit of mankind.