Cancer cell death pathways caused by photothermal and photodynamic effects through gold nanoring induced surface plasmon resonance

Abstract

The different death pathways of cancer cells under the conditions of the photothermal (PT), effect, photodynamic (PD) effect, and their combination are evaluated. By incubating cells with Au nanoring (NRI) either linked with the photosensitizer, AlPcS, or not, the illumination of a visible continuous laser for exciting the photosensitizer or an infrared femtosecond laser for exciting the localized surface plasmon resonance of Au NRI, leads to various PT and PD conditions for study. Three different staining dyes are used for identifying the cell areas of different damage conditions at different temporal points of observation. The cell death pathways and apoptotic evolution speeds under different cell treatment conditions are evaluated based on the calibration of the threshold laser fluences for causing early-apoptosis (EA) and necrosis (NE) or late-apoptosis (LA). It is found that with the PT effect only, strong cell NE is generated and the transition from EA into LA is faster than that caused by the PD effect when the EA stage is reached within 0.5 h after laser illumination. By combining the PT and PD effects, in the first few hours, the transition speed becomes lower, compared to the case of the PT effect only, when both Au NRIs internalized into cells and adsorbed on cell membrane exist. When the Au NRIs on cell membrane is removed, in the first few hours, the transition speed becomes higher, compared to the case of the PD effect only.

Photosensitiser-gold nanoparticle conjugates for photodynamic therapy of cancer

“…55 The The human epidermal growth factor receptor 1, also known as EGFR, has also been widely targeted via antibodies. [57][58][59][60] Kuo and co-workers synthesised CTAB-stabilised AuNRs (35 nm × 9.3 nm in size) conjugated to poly(styrene-altmaleic acid) (PSMA), to which the photosensitiser ICG was electrostatically attached. 57 Additionally, the negatively charged ICG the absence of light but killed up to 98 % cells upon irradiation.…”

“…58 The Kiang group has also reported the use of anti-EGFR antibodies for targeted PDT. 59,60 This research group focuses on the synthesis of gold nanorings functionalised with a thiolated PEG, a sulfonated aluminium phthalocyanine (AlPcS) and a 16-mercaptohexadecanoic acid, acting as the linker to anti-EGFR antibodies. The group was able to perform PDT in combination with PTT using an irradiation wavelength of 1,064 nm for PTT but also as a two-photon excitation of the AlPcS photosensitiser for PDT, in conjunction with the more conventionally used 660 nm wavelength for the irradiation of phthalocyanines for PDT.…”

“…The group was able to perform PDT in combination with PTT using an irradiation wavelength of 1,064 nm for PTT but also as a two-photon excitation of the AlPcS photosensitiser for PDT, in conjunction with the more conventionally used 660 nm wavelength for the irradiation of phthalocyanines for PDT. 59,60 Lectins and carbohydrates…”

<p>Pathological Mechanism of Photodynamic Therapy and Photothermal Therapy Based on Nanoparticles</p>

“…The PTT effect is due to the LSP resonance of gold nanoparticles. 64 The way to cause rapid necrosis or rapid development of late apoptosis is to incubate the cells with only AuNRs and irradiate them with a 1064-nmde laser close to the LAP formant of Au to achieve a separate PTT strategy 65 (Figure 1).…”

Enhancements of Cancer Cell Damage Efficiencies in Photothermal and Photodynamic Processes through Cell Perforation and Preheating with Surface Plasmon Resonance of Gold Nanoring

“…In this spectral range, light can penetrate into tissue the deepest [22,23,24,25]. When Au NRIs taken up by cells are excited by a light source with the wavelength close to its LSP resonance peak, the enhanced absorption can produce a strong PT effect for causing cancer cell damage [22,23,24,25]. By linking a photosensitizer to Au NRIs for cell uptake, i.e., using Au NRIs as the photosensitizer carrier, an illumination to excite the photosensitizer can result in the PD effect.…”