Date Published: March 18, 2018
Publisher: Tabriz University of Medical Sciences
Author(s): Mohammad Ali Behnam, Farzin Emami, Zahra Sobhani, Omid Koohi-Hosseinabadi, Amir Reza Dehghanian, Seyed Mojtaba Zebarjad, Mohammad Hadi Moghim, Ahmad Oryan.
Purpose: Plasmonic photo thermal therapy (PPTT) is a therapeutic method in which the photon energy is rapidly transformed into heat via a series of radiative and non-radiative phenomena to ablate cancer. Plasmonic NPs, such as silver NPs (Ag NPs), have considerable properties in optical absorbance. Furthermore, good thermal conductivity and cell penetration ability of carbon nanotubes (CNTs) could improve the efficacy of Ag NPs for PPTT. Decoration of the multi-walled carbon nanotubes (MWCNTs) with silver has been developed to enhance thermal conductivity of the MWCNT particles.
Cancer is a disease defined by invasive and uncontrolled growth of abnormal cells. Current primary treatments for cancer are surgery, radiation, and chemotherapy. Surgical extirpation is efficacious in primary tumors, but limited to surgical detectable and accessible tumors. Chemotherapy is the other method but limited to the drug dosage forms and their side effects.1 Radiation, a complementary method, is used to exterminate the remaining cancer cells after surgery, but it could be harmful to the healthy tissues in the vicinity of the tumor region or in the path of the radiation ray.1,2 Recently, genesis of a novel class of photo thermally sensitized agents, nano-scale particles, called plasmonic photo thermal therapy (PPTT), made a revolution in photo thermal therapy (PTT). After entrance of nanoparticles (NPs) into the tumor sites, near infrared (NIR) or visible light excitation of NPs could induce a moderate temperature increment in vicinity of the NPs,3 termed as hyperthermia, to destroy the cancer cells clinically.4,5 Hyperthermia is generally determined as heating tissues to a temperature in the range of 41-47°C for several minutes.6 Tumors are selectively damaged due to their reduced heat tolerance in comparison to normal tissues. One of the specific characteristics of this method is to treat recurrent tumors conveniently while NPs are available in the tumor site. Hyperthermia makes irreversible cell damage by rupturing cell membranes, denaturing proteins, and cell cavitation and degeneration leading to cellular necrosis and apoptosis.1,7 Thermal tumor therapies, based on hyperthermia phenomenon,8 has been expanded by different kinds of nanomaterials, including gold NPs,9,10 silver NPs,11,12 and carbon nanotubes (CNTs).13
Integration of CNTs with silver increased the optical absorption of CNTs significantly. CNT/Ag NPs induced heat generation and resulted in considerable damage to melanoma cancer in vivo. Animal studies demonstrated high efficiency of this novel NPs in PPTT method with the specific parameters of excitation.
This work was financially supported by Shiraz University of Medical Sciences (grant No. 15986). We would like to thank Dr. Ali Mashreghi, a faculty member of Materials Science and Engineering Department, Shiraz University of Technology, Shiraz, Iran, for his helpful comments.
The protocol of the study was approved by Ethical Committee of Shiraz University of Medical Sciences (aproval number 15986).
The authors declare that they have no conflict of interests. Authors disclose all relationships or interests that could have direct or potential influence or impart bias on the work.