ABSTRACT
Objective To explore whether inhibiting autophagy can enhance the sensitivity of photothermal treatment under mild photothermal conditions. Methods CQ@PLGA@PDA NPs were prepared by an improved double emulsification method and a PDA-based surface modification method. After basic characterization, CCK-8 method was used to detect the cytotoxicity of nanoparticles; the near-infrared laser irradiation nanoparticle solution was used to detect the heating effect; CCK-8 method and live-dead cell staining were used to detect the killing effect of tumor cells; Western blot was used to detect the expression of autophagy-related proteins. Results The CQ@PLGA@PDA NPs were successfully prepared, with a particle size of 253.10±2.39 nm, a zeta potential of -22.57±0.80 mV, uniform particle size and good dispersion. The temperature of nanoparticle solution increased to 45℃ after the near-infrared laser irradiation for 10 min. CQ@PLGA@PDA NPs had no obvious toxicity to cells. The survival rates of breast cancer cell MDA-MB-231 and mouse embryonic fibroblast NIH-3T3 cell were above 95%. The inhibition of autophagy under mild photothermal conditions could improve the sensitivity of photothermal therapy. Conclusion The prepared CQ@PLGA@PDA NPs have good photothermal performance and high biological safety; by inhibiting autophagy, they can effectively kill tumor cells under mild photothermal conditions(< 50℃).
ABSTRACT
Objective: To develop a gold nanoparticles complex conjugated with interferon-gamma (IFN-γ) and methionine along with application of hyperthermia using near-infrared laser beams for the treatment of cancer cells. Methods: Gold nanorods (10 nm) were conjugated with IFN-γ and methionine using carbodiimide family and characterized after purification by dialysis bags. Breast cancer cells were cultured and incubated with gold nanorods at different concentrations followed by irradiation with near-infrared laser beam. Samples were then evaluated for their viability in order to determine the effect of treatment and variables by MTT assy. Results: Zetasizer results confirmed the conjugation of gold nanorods with methionine and IFN-γ. The median percentage of cell viability in 0.30 μg/mL concentration of gold nanorods was 82%. The cell viability reached to 85% at the same concentration of gold nanorods, which existed in the assayed complex. The results of MTT assay showed that the 0.60 μg/mL concentration of gold nanoparticles complex was toxic on tumor cells (P < 0.05). After exposure to hyperthermia, the viability of cells at 6 min decreased to 77% in 0.30 μg/mL concentration of gold nanorods complex. Conclusions: The size and concentration of gold nanorods was not cytotoxic. However, their presence during irradiation near-infrared laser increased the number of dead cells during the treatment of cells.
ABSTRACT
The transitional near-infrared (NIR) laser was defined as ranging from 1.3μm to 1.4μm, within which the most sensitive tissue to laser damage changed from the retina to the cornea.The ocular damage effect has attracted much attention due to the increased varieties and output power of laser in this spectrum region in recent years.Compared with visible and mid-and-far infrared wavelengths, the ocular damage effect induced by transitional NIR wavelengths has many peculiarities and impact factors due to the bulk absorptionby ocular media.This paper reviews the existing ocular damage threshold data and analyzes the characteristics, impact factors and unresolved issues relating to ocular effects induced by laser radiation over the transition zone.