Photothermal therapy (PTT) is emerging as an effective treatment modality for
cancer due to its noninvasive nature. However, the pro-inflammatory necrotic cell death during PTT limits its successful clinical application. Here, we have developed
quercetin (QE)-loaded biodegradable plasmonic nanoparticles that can specifically induce apoptosis in
cancer cells after PTT. We have synthesized
gold-coated
liposome (LiposAu) and QE-loaded
gold-coated
liposome (QE-LiposAu) nanoparticles by in situ reduction of
chloroauric acid with
ascorbic acid in the presence of bare
liposomes (Lipos) or QE-loaded
liposomes (QE-Lipos), respectively. The
gold coating was confirmed by transmission electron microscopic analysis, dynamic light scattering, and ΞΆ potential measurements. LiposAu and QE-LiposAu nanoparticles showed a similar level of temperature rise upon 750 nm near-infrared (NIR)
laser (650 mW, 3 W cm-2) irradiation. The photothermal conversion efficiency of QE-LiposAu nanoparticles was determined to be ∼75%. The efficacy of PTT was found to be dependent on the internalization efficiency of LiposAu nanoparticles in
cancer cells. Importantly, QE-LiposAu nanoparticles showed increased PTT efficacy over LiposAu nanoparticles in
hepatocellular carcinoma cells (Huh-7). Moreover, QE-LiposAu nanoparticles induced apoptosis-mediated cell death after the PTT, and the extent of apoptosis was significantly higher than the LiposAu nanoparticles in Huh-7 cells. Further, QE-LiposAu nanoparticles-mediated PTT depolymerized microtubules network, suppressed Hsp70 expression, and caused DNA damage. QE-LiposAu nanoparticles were also found to be hemocompatible. The results together suggested that biodegradable QE-LiposAu nanoparticles are promising photothermal agents for
cancer therapy.