Updates on metallic nanoparticles applications in bioremediation, biomedicine and biosensing 

Simona Cavalu, Luminita Fritea, Florina Groza

1 Faculty of Medicine and Pharmacy, University of Oradea, P-ta 1 Decembrie 10, 410087, Oradea, Romania

Introduction 

Bio-synthesized Ag, Au and ZnO NPs have received great attention in recent years for their potential to combat infectious diseases by closing the gaps in current antimicrobial formulation techniques, eradicating drugs resistant microorganisms. Recently, we reported the remediation of methylene blue dye from wastewater by using ZnO NPs loaded on nanoclay, the efficiency of removal varied from 90 to 97%. We have also developed FeO NPs as an efficient nanocatalyst for heavy metal adsorption and water treatment, via the chemical route, offering better potential in comparison to other strategies for environmental applications.

Size-dependent antibacterial and antidiabetic AgNPs were also synthesized using solvent extraction of Rosa indica L. Petals. On the other hand, the antibacterial and antifungal properties of AgNPs were demonstrated to provide a synergic effect towards E. faecalis when loaded in CNTs with CHX 2%. This approach clearly suggest that our results are supportive of the near future potential of nanoparticles in clinical endodontics. 

Biological and “eco-friendly” production of selenium nanoparticles was also performed and nanostructured surface based on selenium nanoparticles was demonstrated to improve performances of titanium mesh for cranioplasty.

In terms of diagnostic procedure, the modification of graphene surfaces with metal nanoparticles can significantly increase the electrochemical performance of (bio)sensors, especially by enhancing the signal transduction.

Experimental

Different strategies were applied in order to synthesize AgNPs, AuNPs, ZnPNs and FeNPs. Metallic NPs produced from plant extracts are stable and monodispersible when the pH, incubation time, mixing ratio, and temperature are all accurately regulated. Although biological synthesis of MNPs has numerous advantages, a polydispersity of the nanoparticles remains a disadvantage. Optimization of the growth medium composition and parameters such as temperature, pH, salt concentration, incubation period, mixing ratio, redox conditions, irradiation, and aeration are the necessary steps in almost every type of biological process

Results and conclusions. Different routes of synthesis to create metallic nanoparticles of different characteristics and possible applications were employed. Both the functions and roles of MNPs as a drug delivery system, diagnostic agent and other potential theranosticpurposes against metabolic disorders, photocatalysis applications, as well as wastewater treatments, are discussed. The advantages and challenges of MNPs owing to their superior surface catalytic activities were highlighted. However, for engineered MNPs to reach their true potential, there are still a number of unanswered questions.

References. [1] Rajendran, S.; Wanale, S.G.; Gacem, A.; Yadav, V.K. et al. Nanostructured Iron Oxides: Structural, Optical, Magnetic, and Adsorption Characteristics for Cleaning Industrial Effluents.

Crystals 2023, 13, 472. 

[2] Marica, A.; Fritea, L.;Banica, F.; Sinescu, C.; Iovan, C.;Hulka, I.; Rusu, G.; Cavalu, S. Carbon

Nanotubes for Improved Performances of Endodontic Sealer. Materials 2021, 14, 4248. 

[3] Fritea, L.; Bănică, F.; et al. S. A gold nanoparticles - graphene based electrochemical sensor forsensitive determination of nitrazepam, Journal of Electroanalytical Chemistry, 2018;830-831:63.

[4] Balu, S.K.; Andra, S. et al. et al. Size-Dependent Antibacterial, Antidiabetic, and Toxicity of Silver Nanoparticles Synthesized Using Solvent Extraction of Rosa indica L. Petals. Pharmaceuticals 2022, 15, 689.