title: Numerical investigation of thermal response of laser-irradiated biological tissue phantoms embedded with gold nanoshells.
abstract: The work presented in this paper focuses on numerically investigating the thermal response of gold nanoshells-embedded biological tissue phantoms with potential applications into photo-thermal therapy wherein the interest is in destroying the cancerous cells with minimum damage to the surrounding healthy cells. The tissue phantom has been irradiated with a pico-second laser. Radiative transfer equation (RTE) has been employed to model the light-tissue interaction using discrete ordinate method (DOM). For determining the temperature distribution inside the tissue phantom, the RTE has been solved in combination with a generalized non-Fourier heat conduction model namely the dual phase lag bio-heat transfer model. The numerical code comprising the coupled RTE-bio-heat transfer equation, developed as a part of the current work, has been benchmarked against the experimental as well as the numerical results available in the literature. It has been demonstrated that the temperature of the optical inhomogeneity inside the biological tissue phantom embedded with gold nanoshells is relatively higher than that of the baseline case (no nanoshells) for the same laser power and operation time. The study clearly underlines the impact of nanoshell concentration and its size on the thermal response of the biological tissue sample. The comparative study concerned with the size and concentration of nanoshells showed that 60nm nanoshells with concentration of 5×1015mm-3result into the temperature levels that are optimum for the irreversible destruction of cancer infected cells in the context of photo-thermal therapy. To the best of the knowledge of the authors, the present study is one of the first attempts to quantify the influence of gold nanoshells on the temperature distributions inside the biological tissue phantoms upon laser irradiation using the dual phase lag heat conduction model.
authors.affiliation: Department of Mechanical Engineering, Indian Institute of Technology Bombay, Mumbai 400076, India.
authors.forename: Akshay
authors.initials: A
authors.lastname: Phadnis
authors.affiliation: Department of Mechanical Engineering, Indian Institute of Technology Bombay, Mumbai 400076, India.
authors.forename: Sumit
authors.initials: S
authors.lastname: Kumar
authors.affiliation: Department of Mechanical Engineering, Indian Institute of Technology Bombay, Mumbai 400076, India. Electronic address: atulsr@iitb.ac.in.
authors.forename: Atul
authors.initials: A
authors.lastname: Srivastava
mesh_terms: D000465:Algorithms; D003198:Computer Simulation; D003287:Contrast Media / Q000737:chemistry* / Q000627:therapeutic use; D006046:Gold / Q000737:chemistry* / Q000627:therapeutic use; D006358:Hot Temperature; D006801:Humans; D006979:Hyperthermia, Induced / Q000379:methods; D053685:Laser Therapy / Q000379:methods; D007834:Lasers; D008954:Models, Biological; D057145:Nanoshells / Q000737:chemistry* / Q000627:therapeutic use; D009369:Neoplasms / Q000628:therapy; D010789:Phototherapy / Q000379:methods; D013814:Thermal Conductivity
chemical_list: D003287:Contrast Media; D006046:Gold
keywords: Bio-heat transfer; Gold nanoshells; Non-Fourier heat conduction; Optical inhomogeneity; Photo-thermal therapy; Radiative transfer equation