Gongalsky Maxim, Gvindzhiliia Georgii, Tamarov Konstantin, Shalygina Olga, Pavlikov Alexander, Solovyev Valery, Kudryavtsev Andrey, Sivakov Vladimir, Osminkina Liubov A
Department of Physics, Lomonosov Moscow State University, Leninskie Gory 1, 119991 Moscow, Russia.
University of Eastern Finland - Kuopio Campus, Yliopistonranta 1, 70210 Kuopio, Finland.
ACS Omega. 2019 Jun 19;4(6):10662-10669. doi: 10.1021/acsomega.9b01030. eCollection 2019 Jun 30.
The radiofrequency (RF) mild hyperthermia effect sensitized by biodegradable nanoparticles is a promising approach for therapy and diagnostics of numerous human diseases including cancer. Herein, we report the significant enhancement of local destruction of cancer cells induced by RF hyperthermia in the presence of degraded low-toxic porous silicon (PSi) nanowires (NWs). Proper selection of RF irradiation time (10 min), intensity, concentration of PSi NWs, and incubation time (24 h) decreased cell viability to 10%, which can be potentially used for cancer treatment. The incubation for 24 h is critical for degradation of PSi NWs and the formation of silicic acid ions H and HSiO in abundance. The ions drastically change the solution conductivity in the vicinity of PSi NWs, which enhances the absorption of RF radiation and increases the hyperthermia effect. The high biodegradability and efficient photoluminescence of PSi NWs were governed by their mesoporous structure. The average size of pores was 10 nm, and the sizes of silicon nanocrystals (quantum dots) were 3-5 nm. Degradation of PSi NWs was observed as a significant decrease of optical absorbance, photoluminescence, and Raman signals of PSi NW suspensions after 24 h of incubation. Localization of PSi NWs at cell membranes revealed by confocal microscopy suggested that thermal poration of membranes could cause cell death. Thus, efficient photoluminescence in combination with RF-induced cell membrane breakdown indicates promising opportunities for theranostic applications of PSi NWs.
可生物降解纳米颗粒敏化的射频（RF）温和热疗效应是治疗和诊断包括癌症在内的多种人类疾病的一种有前景的方法。在此，我们报道了在降解的低毒多孔硅（PSi）纳米线（NWs）存在下，RF热疗诱导的癌细胞局部破坏显著增强。适当选择RF照射时间（10分钟）、强度、PSi NWs的浓度和孵育时间（24小时）可将细胞活力降低至10%，这有可能用于癌症治疗。24小时的孵育对于PSi NWs的降解和大量硅酸离子H和HSiO的形成至关重要。这些离子极大地改变了PSi NWs附近的溶液电导率，从而增强了RF辐射的吸收并增加了热疗效果。PSi NWs的高生物降解性和高效光致发光由其介孔结构决定。平均孔径为10纳米，硅纳米晶体（量子点）的尺寸为3 - 5纳米。孵育24小时后，观察到PSi NW悬浮液的光吸收、光致发光和拉曼信号显著降低，这表明PSi NWs发生了降解。共聚焦显微镜显示PSi NWs定位于细胞膜，这表明膜的热穿孔可能导致细胞死亡。因此，高效光致发光与RF诱导的细胞膜破裂相结合，为PSi NWs的治疗诊断应用提供了有前景的机会。
