Table 2.
Summary of reduction of toxicity strategies employed in metal nanoparticles and the techniques used to assed their characterization and therapeutic efficacy (ND: no data available).
| Stragey Employed | Type of Metal NP | Functionalitzation Stragey | Physicochemical Characteritzation | In Vitro Studies | In Vivo Studies | References |
|---|---|---|---|---|---|---|
| Surface functionalization | Gold nanoparticles | PEG-SH and PG-NH2 groups | TEM/HRTEM, UV-Vis spectroscopy | Citotoxicity assay in SAOS-2 cell line cultivated in McCoy’s 5A medium with 15% heat-inactivated FBS, penicillin and streptomycin | ND | [134] |
| Surface functionalization | Zinc nanoparticles | PEG | FTIR | Citotoxicity assay in THP-1 immune cells | ND | [135] |
| Surface functionalization | Gold nanoparticles | Anionic ligands | ND | ND | ND | [137] |
| Antibody funtionalization | Gold coated magnetite | Antibody raanibizumab | SEM, DLS, XRD, TGA | Citotoxicity test by MTT assay | ND | [138] |
| Coating modification | Zinc nanoparticles | Silica coating | TEM, XPS, EDX, FTIR | Citotoxicity assessment in both colorectal epithelial cell lines (SW480 and DLD-1) | ND | [142] |
| Coating modification | Iron oxide nanoparticles | Silica coating | TEM, DLS and potential measurements | Citotoxicity assay in HeLa and A549 cells | ND | [143] |
| Coating modification | Silver nanoparticles | Silica coating | TEM and SEM images, optical absortion | Toxicity evaluation with E. coli bacteria | ND | [26] |
| Coating modification | Copper nanoparticles | Chitosan coating | XPS, XRD, TEM, DLS | Citotoxicity with human alveolar epithelial cell (A549) using standard MTS assay | In vivo study using mice by nasal administration to investigate inflammatory responses | [146] |
| Size modification | Silver Nanoparticles | ND | TEM, DLS, Z-potential | Citotoxicity study with murine peritoneal macrophage cell line (RAW 264.7) and L929 fibroblasts | ND | [149] |
| Size modification | Gold nanoparticles | ND | TEM, ICP-MS | In vitro study with HeLa cells by MTT assay | Mice intraperitoneal injection into BALB/C at a dose of 8 mg/kg/week | [151] |
| Shape modification | Gold nanoparticles | chitosan | HR Tem images | In vitro study into four cancer cell lines: AGS, HepG2, HT29, HeLa by MTT assay | ND | [156] |