A nanotechnology research product as high potential Antiviral research candidate against COVID-19

SILNAN-50 is a nanotechnology-based research product which can be an antiviral drug research candidate as a potential treatment against COVID-19 virus. It is developed by Achal Agrawal who is a researcher and CEO of, a pharma company specializing in cGMP production of rare and atypical active pharmaceutical ingredients.

Mr. Agrawal has been researching on Silver Nanoparticles since last 2 years and has been doing extensive self-experimentation by using his prepared Silver Nanosuspension on his viral and other infections.

SILNAN-50 is basically a Citrate stabilized suspension of Silver Nanoparticles of average size between 10 to 15 nanometres. The strength of Silver in the suspension is only 0.005% (50 ppm). The product contains microbe free Purified / Distilled water, Suspended Silver Nanoparticles and Trisodium Citrate as a stabilizer and reducing agent. The product is stable for few months when stored in a refrigerator.


Silver Nanoparticles are very well established as broad spectrum antimicrobial and are used now days in many products and medical devices like wound dressings, implants, etc for its antimicrobial properties. There is ample evidence of broad-spectrum antiviral activity of Silver Nanoparticles in form of authentic published research papers. The antiviral activity of Silver Nanoparticles has been found against over 24 different viruses including HIV-1, HSV-1, Respiratory syncytial virus, Monkeypox virus, Influenza virus, Hepatitis B Virus, etc. No other antiviral agent exhibits such broad-spectrum antiviral activity. Broad Spectrum and non-specific antiviral are the need of the hour when there is no or little information and knowledge about the COVID-19 virus.

The broad spectrum and non-specific mode of action of Silver Nanoparticles is because of its nano size much smaller than the size of microbes, due to which it can easily penetrate the cell walls and is presumed that it inhibits the growth by suppressing respiratory enzymes and electron transport components and through interference with DNA functions.

It is known that Silver Nanoparticles bind with viral envelope glycoprotein and inhibit the virus by binding to the disulfide bond regions of the CD4 binding domain within the HIV-1 viral envelope glycoprotein gp120, as suggested by Elechiguerra [4]. This fusion inhibition was also demonstrated by Lara and colleagues [2]

The antiviral activity of AgNPs has been reported on the hepatitis B virus (HBV) using a HepAD38 human hepatoma cell line. There is evidence of high binding affinity of nanoparticles for HBV DNA and extracellular virions with different sizes (10 and 50 nm). It has been demonstrated that AgNPs could also inhibit the production of HBV RNA and extracellular virions in vitro.

The presumed mode of action is such that viruses cannot develop resistance against Silver as compared to antibiotics as Silver attacks a broad range of targets in the microbes. Viruses possess no system of defence against AgNPs and their endlessly evolving cycle of viral protein mutations cannot shield their recurrent vulnerability to the denaturing action of Silver.

In fact, one research [5] has proven that the microbes killed due to the action of silver, start killing other living microbes like "Zombie" and act as reservoir of silver, which is re-targeted to the living microbes.

Modes of Antiviral Action of Silver Nanoparticles.

Images obtained from: Stefania G, Annarita F, & ors, 2011, PMC 6264685 ; Naik & Kaushik, Journal of applied microbiology, 2017; Rout George Kerry Et al, Nanomedicine: Nanotechnology, Biology and Medicine.


SILNAN-50, which is a 50 ppm Silver Nanosuspension is suggested to be delivered in best effective way through Nebulization. Nebulization will deliver the it very effectively in the whole respiratory system, which is the main area of activity of COVID-19. The it can also be administered Sublingually & Buccally by keeping the suspension under the tongue, between gums and cheek. Gargling with the SILNAN-50 can also be effective in initial stages and as prevention. The researcher, his family members and close friends have used the Silver Nanosuspension for over 2 years against viral infections, without any observed side effect (used as a self-research and self-experimentation).


The established it of Silver for Argyria (only known mild & benign side effect) is 10 grams for total lifetime intake. For COVID-19 treatment we can consider 1% dose out of total lifetime it of 10 grams which comes to 100 milligrams. If we consider a 14 days treatment period, then the daily dose comes to approx 7 milligrams. 7 milligrams / day of Silver is equivalent to 140 ml of SILNAN-50. A daily dose of 50-100 ml SILNAN-50 in all forms of administration [Nebulization, Sublingual & Buccal] can prove to be sufficient.


Cost of 1 litre of SILNAN-50 is approx Rs. 50 (< 1$). Cost of proposed maximum daily dose of 100 ml is just Rs. 5.


Silver has been used since ages as a medicine. Ayurveda recognizes Silver “Rajata” as medicine. Silver has existed in allopathic medicine as Argyrol, Electrargol, Protargol, Collargol, Colloidal Silver, etc since more than 100 years and is officially listed in many international pharmacopoeias [6]. There is no known toxicity of Silver except a mild and benign toxicity called as Argyria which is developed by administering very high doses of ionic silver. Argyria was reported in order times but now is very less reported due to betterment in the technology of Silver based products. Silver Nanoparticles may exhibit cytotoxicity but at higher dosage levels and is also one of the reasons for its potential use as an anticancer and it has been proven effective in cancer treatment as well. The Silver Nanoparticles are non-ionic reduced form of Silver and have not exhibited any acute toxicity or carcinogenicity. The silver nanoparticles being nano sized are very well distributed in the body and are also easily excreted out as it can pass through any bio-membrane and biological barriers. WHO has reported an oral NOEL for Argyria in humans for a total lifetime intake of 10 g of Silver. EPA has documented the toxicity assessment of Silver (CASRN 7440-22-4) and reports no evidence of human carcinogenicity or mutagenicity. EPA and WHO also consider Silver as safe disinfectant for drinking water.


Silver Nanoparticles and the developed research product SILNAN-50 can be a high potential research candidate against COVID-19 due to already exhibited broad spectrum and non-specific antiviral activity of Silver Nanoparticles. A very important aspect is that if the it shows success then it can be easily made on large scales in very short timeframe with the resources already available in the country. The cost of the research product is negligible.

The researcher has no commercial interest in this product and would like to dedicate their research to the country and humanity.

This product is still a research subject and presently there are no approvals to manufacture it as a "drug", "new drug" or "new drug for clinical trial".

The company is trying to approach the government to use this research product for conducting trials on the COVID-19 infected patients and conduct an advance stage clinical trial directly, looking at the current situation of the declared pandemic.


  • Silver Nanoparticles as Potential Antiviral Agents. Stefania Galdiero, Annarita Falanga, Mariaterasa Vitiello and Ors, Department of Experimental Medicine, University of Naples,Published in Molecules Oct 2011.
  • Mode of antiviral action of silver nanoparticles against HIV-1. Humberto H Lara, Nilda V Ayala-Nunez. Journal of Nanobiotechnology 2010.
  • Use of Silver Nanoparticles in HIV treatment protocols. Ricardo A. Frazer. Journal of Nanomedicine & Nanotechnology 2012.
  • Interaction of silver nanoparticles with HIV-1. Jose Luis Elechiguerra, Justin L Burt. Journal of Nanobiotechnlogy 2005.
  • Antibacterial activity of silver-killed bacteria: the “zombies” effect. Racheli Ben-Knaz Wakshlak, Rami Pedahzur. Scientific Reports 2015.
  • Colloidal Silver European Pharmacopoeia monograph 2281.
  • Promising Cure for URTI Pandemics, Including H5N1 and SARS, by Eric Gordon, MD and Kent Holtorf, MD, 2006.
  • Silver nanoparticles are broad-spectrum bactericidal and virucidal compounds. Humberto H Lara, Journal of Nanobiotechnology, 2011.
  • The silver lining: towards the responsible and limited usage of silver. Naik & Kaushik, Journal of applied microbiology, 2017.
  • Exposure of silver-nanoparticles and silver-ions to lung cells in vitro at air-liquid interface. Fabian Herzog, Particle and Fibre Technology.
  • A novel in vitro metric predicts in vivo efficacy of inhaled silver-based antimicrobials in a murine Pseudomonas aeruginosa pneumonia model. Parth N. Shah, Scientific Reports April 2018.
  • In Vitro and Murine Efficacy and Toxicity Studies of Nebulized SCC1, a Methylated Caffeine-Silver(I) Complex, for Treatment of Pulmonary Infections. Carolyn L. Cannon. Antimicrobial Agents and Chemotherapy, American Society for Microbiology.
  • Nano-based approach to combat emerging viral (NIPAH virus) infection, Rout George Kerry Et al, Nanomedicine: Nanotechnology, Biology and Medicine, Vol 18, 2019.
  • Researcher Information

    Mr. Achal Agrawal (CEO)
    Cell No: +91 93525 12033

    Project Website: