Citrate-stabilized Gold Nanorods: Optimal Production, Physicochemical Properties And Cytotoxicity Investigation

Objective: The CTAB-stabilized AuNRs were exchanged with the surfactant PSS to prepare sodium citrate-stabilized gold nanorods(citrate)Stabilized AuNRs)and compared the physicochemical properties of CTAB-stabilized AuNRs and citratestabilized AuNRs,including refractive index sensitivity and surface-enhanced Raman scattering(SERS)effects.On this basis,the cytotoxicity of two different surfacemodified gold nanorods was investigated.Methodology: The prepared CTAB-stabilized AuNRs were replaced by two substitutions of polystyrene sulfonate(PSS),and then replaced with sodium citrate to replace the PSS,thereby The prepared CTAB-stabilized AuNRs were subjected to two PSS displacements and replaced by sodium citrate instead of PSS,thereby obtaining citrate-stabilized AuNRs;and CTAB-stabilized AuNRs and citrate-stabilized AuNRs in different concentrations of water/glycerol mixture.Comparison of refractive index sensitivity(RIS)test results;comparison of the physicochemical characteristics of SERS spectroscopy of CTAB-stabilized Au NRs and citrate-stabilized AuNRs;further cell experiments to culture human umbilical vein endothelial cells(HUVECs),adding two Different concentrations of gold nanorod solutions were tested by CCK-8 kit for cell proliferation/toxicity and flow cytometry for cell apoptosis.Results:(1)The simple prepared citrate-stabilized AuNRs UV-visible-near-infrared spectrograms showed no blue shifts of 30 nm in the case of significant changes in the peak morphology.The CTAB-stabilized AuNRs had a wavelength ? of 803 nm,and the final citrate-stabilized AuNRs had a wavelength ? of 773 nm.UV-vis and near-infrared spectroscopy(UV-vis),transmission electron microscopy(TEM),Zeta potentials,and computer simulations were used to confirm that the citrate-stabilized AuNRs were finally obtained.(2)The refractive index sensitivity of longitudinal localized surface plasmon resonance(LSPR)of citrate-stabilized AuNRs is 356 nm / RIU(refractive index unit),and that of CTAB stabilized AuNRs is 204 nm / RIU.Therefore,the refractive index sensitivity of the former is better than the latter.(3)SERS intensity of citrate-stabilized AuNPs is 36 times stronger than that of spherical AuNPs.In contrast,CTAB-stabilized AuNRs have no detected Raman signal.(4)HUVECs cells were subjected to cytotoxicity and apoptosis assay respectively.Different concentrations of CTAB-stabilized Au NRs and citrate-stabilized AuNRs were added,and the apoptosis rate of endothelial cells in citrate-stabilized AuNRs group was not significantly different from the normal group.CTAB-stabilized In the AuNRs group,the proportion of apoptotic cells increased significantly with the increase of the concentration,and the cell activity decreased.Conclusion: 1)This study obtained a strategy for the preparation of citrate-stabilized AuNRs in an operable,repeatable,and scalable manner.2)The citrate-stabilized AuNRs are more dominant than the optical and spectroscopic properties of CTABstabilized AuNRs;3)citrate-stabilized AuNRs significantly reduce cytotoxicity and increase biocompatibility;4)expand AuNRs in biomedical and clinical medicine The basic and applied value of the field.