title: Green Microwave-Assisted Combustion Synthesis of Zinc Oxide Nanoparticles with Citrullus colocynthis (L.) Schrad: Characterization and Biomedical Applications.
abstract: In this paper, a green microwave-assisted combustion approach to synthesize ZnO-NPs using zinc nitrate andCitrullus colocynthis(L.) Schrad (fruit, seed and pulp) extracts as bio-fuels is reported. The structure, optical, and colloidal properties of the synthesized ZnO-NP samples were studied. Results illustrate that the morphology and particle size of the ZnO samples are different and depend on the bio-fuel. The XRD results revealed that hexagonal wurtzite ZnO-NPs with mean particle size of 27-85 nm were produced by different bio-fuels. The optical band gap was increased from 3.25 to 3.40 eV with the decreasing of particle size. FTIR results showed some differences in the surface structures of the as-synthesized ZnO-NP samples. This led to differences in the zeta potential, hydrodynamic size, and more significantly, antioxidant activity through scavenging of 1, 1-Diphenyl-2-picrylhydrazyl (DPPH) free radicals. In in vitro cytotoxicity studies on 3T3 cells, a dose dependent toxicity with non-toxic effect of concentration below 0.26 mg/mL was shown for ZnO-NP samples. Furthermore, the as-synthesized ZnO-NPs inhibited the growth of medically significant pathogenic gram-positive (Bacillus subtilisand Methicillin-resistantStaphylococcus aurous) and gram-negative (Peseudomonas aeruginosaandEscherichia coli) bacteria. This study provides a simple, green and efficient approach to produce ZnO nanoparticles for various applications.
authors.affiliation: Department of Bioprocess Technology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, UPM Serdang, Selangor 43400, Malaysia. azisusan@gmail.com.
authors.forename: Susan
authors.initials: S
authors.lastname: Azizi
authors.affiliation: Department of Bioprocess Technology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, UPM Serdang, Selangor 43400, Malaysia. farizan@upm.edu.my.|Laboratory of Biopolymer and Derivatives, Institute of Tropical Forestry and Forest Products, Universiti Putra Malaysia, UPM Serdang, Selangor 43400, Malaysia. farizan@upm.edu.my.
authors.forename: Rosfarizan
authors.initials: R
authors.lastname: Mohamad
authors.affiliation: Department of Chemistry, Shiraz Branch, Islamic Azad University, Shiraz 74731-71987, Iran. mahnaz.chem@gmail.com.
authors.forename: Mahnaz
authors.initials: M
authors.lastname: Mahdavi Shahri
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000494:pharmacology; D000975:Antioxidants / Q000737:chemistry / Q000494:pharmacology; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D065986:Citrullus colocynthis / Q000737:chemistry*; D003102:Colloids; D055772:Green Chemistry Technology; D051379:Mice; D008826:Microbial Sensitivity Tests; D008872:Microwaves; D015394:Molecular Structure; D053758:Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D010936:Plant Extracts / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared; D014961:X-Ray Diffraction; D015034:Zinc Oxide / Q000737:chemistry*
chemical_list: D000900:Anti-Bacterial Agents; D000975:Antioxidants; D003102:Colloids; D010936:Plant Extracts; D015034:Zinc Oxide
keywords: Citrullus colocynthis; Combustion method; ZnO nanoparticles; antimicrobial; antioxidant; green synthesis