Purpose: Antimicrobial resistance to antibiotics (AMR) and cancer and two of the main concerns that the healthcare system should face nowadays. Current drugs and antibiotic treatments are becoming ineffective or have plenty of drawbacks. Therefore, new alternatives are needed, and nanotechnology can offer a suitable solution. Despite the increase in the use of nanostructures in the biomedical field, traditional synthesis of such materials is subjected to several disadvantages, such as the production of toxic-by-products and harsh conditions. Therefore, green nanotechnology is presented as a suitable answer, allowing the generation of nanostructures in a quick, cost-effective and environmentally-friendly approach.
Methods: Pathogenic bacteria and human cells -both cancer and healthy ones- were used for the synthesis of metallic nanoparticles similarly. Briefly, different concentrations of metallic salts were added to the cultures once they are clean from additional reducing agents -media in the case of human cells-. Bacteria and cells are cultured in the presence of metallic salts under standard conditions until the generation of nanoparticles, that is followed using microscopy and spectrophotometric techniques. After purification, nanoparticles are used as antimicrobial and anticancer agents using colony counting unit assays and MTS assays, respectively. Characterization of the nanoparticles is used regarding morphology, size, and composition using TEM, SEM, and EDX measurements.
Results: Pathogenic bacteria –such as Escherichia coli or Methicillin-resistant Staphylococcus aureus- are used for the synthesis of bacteriogenic metallic selenium nanoparticles that were characterized in term of size, morphology, and composition. These agents were employed as suitable agents with antimicrobial activity against the same bacteria that synthesized them, showing low cytotoxicity for human dermal fibroblasts (HDF) cells over a range of concentrations up to 250 µg/mL.
The synthesis of metallic nanomaterials using cancer cells –both Melanoma and Glioblastoma human cells- and healthy cells -HDF and HFOB- is reported. Pure metal nanoparticles –palladium or platinum- and bimetallic structures –such as gold-platinum- are readily synthesized using cancerous cells, and after purification, they are used as anticancer agents, showing low cytotoxicity for human cells over a range of concentration between 5 and 75 µg/mL.
Conclusion: Microbiological agents -human cells and pathogenic bacteria- are successfully used as a synthetic machine for the generation of metallic nanoparticles of different compositions with biomedical properties, such as antibacterial and anticancer activity, showing a low cytotoxic effect for healthy human cells. Therefore, they are presented as a suitable approach for the synthesis of nanomaterials in a green fashion, overcoming the main limitations of traditional nanotechnology.