Abstract
Exposure of cells or biological tissues to high-power pulses of terahertz (THz) radiation leads to changes in a variety of intracellular processes. However, the role of heating effects due to strong absorption of THz radiation by water molecules still stays unclear. In this study, we performed numerical modelling in order to estimate the thermal impact on water of a single THz pulse as well as a series of THz pulses. A finite-element (FE) model that provides numerical solutions for the heat conduction equation is employed to compute the temperature increase. A simple expression for temperature estimation in the center of the spot of THz radiation is presented for given frequency and fluence of the THz pulse. It has been demonstrated that thermal effect is determined by either the average power of radiation or by the fluence of a single THz pulse depending on pulse repetition rate. Human dermal fibroblasts have been exposed to THz pulses (with an energy of 15,upmu hbox {J} and repetition rate of 100 Hz) to estimate the thermal effect. Analysis of heat shock proteins expression has demonstrated no statistically significant difference (p < 0.05) between control and experimental groups after 3 h of irradiation.
Highlights
Exposure of cells or biological tissues to high-power pulses of terahertz (THz) radiation leads to changes in a variety of intracellular processes
Temperature increase related to absorption of continuous wave (CW) THz radiation of given power and frequency was initially estimated for w ater[18,19]; more complicated models were presented for the brain and the breast[20]
Our theoretical estimations of temperature rise have been verified through evaluation of expression levels of heat shock proteins (HSP) in human fibroblasts exposed to THz radiation
Summary
Exposure of cells or biological tissues to high-power pulses of terahertz (THz) radiation leads to changes in a variety of intracellular processes. It has been demonstrated that thermal effect is determined by either the average power of radiation or by the fluence of a single THz pulse depending on pulse repetition rate. Water heating effect by the electric field of electromagnetic radiation has been studied theoretically and experimentally through temperature jumps (T-jump) employing both infrared laser and terahertz (THz) pulsed radiation (see, e.g.2,3). In addition to the direct diagnostic techniques used in life sciences to assess thermal impact of THz radiation (e.g., expression of heat shock p roteins[13,16] and infrared c ameras13,17), numerical modeling is actively applied. The present article is devoted to estimation of temperature increase of water due to the absorption of a single THz pulse and a series of pulses in the course of cell irradiation. Our theoretical estimations of temperature rise have been verified through evaluation of expression levels of heat shock proteins (HSP) in human fibroblasts exposed to THz radiation
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
