Time Dynamic Modes of Nano/Bioparticle Heating

Abstract

Nanoparticles are being researched as a noninvasive method for selectively killing cancer cells. With particular antibody coatings on nanoparticles, they attach to abnormal cells of interest (cancer or otherwise). Once attached, nanoparticles can be heated with UV/visible/IR, RF, or X-ray pulses, heating the surrounding area of the cell to the point of death. Researchers often use single-pulse or multipulse modes of laser heating when conducting nanoparticle ablation research. In this chapter, time-dependent simulations and detailed analyses are carried out for different nonstationary pulsed laser–nanoparticle interaction modes, and the advantages and disadvantages of single-pulse and multipulse (set of short pulses) heating of nanoparticles are shown. Simulations are performed for metal nanoparticles in a surrounding biological medium, as well as for healthy and cancerous cell organelles heated by optical, RF, and X-ray pulses. This chapter contains material adapted from our publications [1–3]. A detailed list of references and reviews on a given topic of this chapter can be found in those original papers.

Appendices

Appendix D: Maple Code for Bioparticle Heating in a Multipulse Mode

This appendix contains a Maple code designed for using OTM to find the heating kinetics of healthy and cancerous cell organelles heated in cytoplasm by multipulsed radiation (Slide 21.9). The comments within the Maple code should explain the variables, procedures, and functions that are used.

Note: This code comes directly from the Maple file and is therefore formatted to word-wrap according to Maple standard character-per-line limits.

Homework Exercises

7.2.1 Section 7.1: Modeling Photothermal Heating for Multipulsed Radiation

• 7.1. List the potential advantages of photothermal sensitizers delivered to the tumor.

• 7.2. What are three main categories of factors defining the heating of the nanoparticle?

• 7.3. True or false? Particle heating depends on the properties of the surrounding medium.

• 7.4. What factors stay relatively constant across many nanoparticle heating experiments?

• 7.5. What pulse durations are often used in nanoparticle heating experiments?

• 7.6. Why are gold nanoparticles often used in nanoparticle heating experiments?

• 7.7. Why is water employed as a surrounding medium?

• 7.8. How many radiation pulses are used in nanoparticle heating experiments?

• 7.9. What size range of gold nanoparticles is often used in nanoparticle heating experiments?

• 7.10. What frequency range of pulse generation is often used in nanoparticle heating experiments?

• 7.11. What is a key goal of the multipulse mode of heating nanoparticles?

• 7.12. What function is used to simulate multiple pulses?

• 7.13. What is a heat accumulation effect?

• 7.14. True or false? Multiple pulses produce an accumulative heating effect in metal nanoparticles.

• 7.15. Describe multipulse heating of metal nanoparticles.

• 7.16. True or false? High pulse-generation frequencies do not create an accumulative heating effect in metal nanoparticles.

• 7.17. Why do cell organelles undergo a heat accumulation effect?

• 7.18. True or false? The cell organelles have much lower values of the specific heat than the metal ones.

• 7.19. What are the advantages of multipulse heating of cell organelles?

• 7.20. True or false? A multipulse mode of heating allows us to reduce the energy density of the radiation per pulse but still able to cause biological damage.

• 7.21. How is a desired final temperature of the organelle reached in a multipulse mode of heating?

• 7.22. Is there any difference in the heating kinetics of the mitochondria and cell nuclei? Explain.

• 7.23. Compare multipulse heating kinetics of metal and biological particles.

• 7.24. True or false? The cooling rate has the same values as the heating rate in metal nanoparticles.

7.2.2 Section 7.2: Computer Practicum: Multipulse Mode of Heating Healthy and Cancerous Cell Organelles

• 7.25. How is a thermal model modified to compute multiple pulses?

• 7.26. What conclusions can be made from simulation results of multipulse heating of healthy and cancerous organelles?

• 7.27. True or false? The healthy lysosome reaches a higher temperature and has a longer cooling time than cancerous lysosome.

• 7.28. What are the energy density of radiation and minimum number of pulses that could cause damage to unhealthy lysosomes while keeping healthy lysosomes unharmed?

• 7.29. Perform multipulse heating simulations for a silver nanoparticle of optimal radius in cytoplasm, fat, and tumor surrounding media by using thermal data from Tables 6.1 to 6.4 and the Maple code in Appendix D. Find the optimal radius of the nanoparticle, optimal wavelength of the radiation, absorption efficiency, and energy density of the radiation required to achieve a maximum temperature of the nanoparticle in each surrounding medium. Write a report on your simulation results. Make conclusions about the heating and cooling kinetics of the nanoparticle in a multipulse heating mode.

• 7.30. Perform multipulse heating simulations for a fullerene nanoparticle of optimal radius in cytoplasm, fat, and tumor surrounding media by using thermal data from Tables 6.1 to 6.4 and the Maple code in Appendix D. Find the optimal radius of the nanoparticle, optimal wavelength of the radiation, absorption efficiency, and energy density of the radiation required to achieve a maximum temperature of the nanoparticle in each surrounding medium. Write a report on your simulation results. Make conclusions about the heating and cooling kinetics of the nanoparticle in a multipulse heating mode.

• 7.31. Perform multipulse heating simulations for a polystyrene nanoparticle of optimal radius in cytoplasm, fat, and tumor surrounding media by using thermal data from Tables 6.1 to 6.4 and the Maple code in Appendix D. Find the optimal radius of the nanoparticle, optimal wavelength of the radiation, absorption efficiency, and energy density of the radiation required to achieve a maximum temperature of the nanoparticle in each surrounding medium. Write a report on your simulation results. Make conclusions about the heating and cooling kinetics of the nanoparticle in a multipulse heating mode.

• 7.32. Perform multipulse heating simulations for a glass nanoparticle of optimal radius in cytoplasm, fat, and tumor surrounding media by using thermal data from Tables 6.1 to 6.4 and the Maple code in Appendix D. Find the optimal radius of the nanoparticle, optimal wavelength of the radiation, absorption efficiency, and energy density of the radiation required to achieve a maximum temperature of the nanoparticle in each surrounding medium. Write a report on your simulation results. Make conclusions about the heating and cooling kinetics of the nanoparticle in a multipulse heating mode.

• 7.33. Perform multipulse heating simulations for a carbon nanoparticle of optimal radius in cytoplasm, fat, and tumor surrounding media by using thermal data from Tables 6.1 to 6.4 and the Maple code in Appendix D. Find the optimal radius of the nanoparticle, optimal wavelength of the radiation, absorption efficiency, and energy density of the radiation required to achieve a maximum temperature of the nanoparticle in each surrounding medium. Write a report on your simulation results. Make conclusions about the heating and cooling kinetics of the nanoparticle in a multipulse heating mode.

• 7.34. Perform multipulse heating simulations for an aluminum oxide nanoparticle of optimal radius in cytoplasm, fat, and tumor surrounding media by using thermal data from Tables 6.1 to 6.4 and the Maple code in Appendix D. Find the optimal radius of the nanoparticle, optimal wavelength of the radiation, absorption efficiency, and energy density of the radiation required to achieve a maximum temperature of the nanoparticle in each surrounding medium. Write a report on your simulation results. Make conclusions about the heating and cooling kinetics of the nanoparticle in a multipulse heating mode.

• 7.35. Perform multipulse heating simulations for a magnesium oxide nanoparticle of optimal radius in cytoplasm, fat and tumor surrounding media by using thermal data from Tables 6.1 to 6.4 and the Maple code in Appendix D. Find the optimal radius of the nanoparticle, optimal wavelength of the radiation, absorption efficiency, and energy density of the radiation required to achieve a maximum temperature of the nanoparticle in each surrounding medium. Write a report on your simulation results. Make conclusions about the heating and cooling kinetics of the nanoparticle in a multipulse heating mode.

• 7.36. Perform multipulse heating simulations for a nickel oxidefullerene nanoparticle of optimal radius in cytoplasm, fat, and tumor surrounding media by using thermal data from Tables 6.1 to 6.4 and the Maple code in Appendix D. Find the optimal radius of the nanoparticle, optimal wavelength of the radiation, absorption efficiency, and energy density of the radiation required to achieve a maximum temperature of the nanoparticle in each surrounding medium. Write a report on your simulation results. Make conclusions about the heating and cooling kinetics of the nanoparticle in a multipulse heating mode.

• 7.37. Perform multipulse heating simulations for normal and cancerous cell nuclei in cytoplasm by using thermal data from Tables 6.1 to 6.5 and the Maple code in Appendix D. Write a report on your simulation results according to the Practice Example 6. Make conclusions about how multipulse laser heating would affect cancerous organelles in comparison to healthy organelles.

• 7.38. Perform multipulse heating simulations for normal and cancerous cell mitochondria in cytoplasm by using thermal data from Tables 6.1 to 6.5 and the Maple code in Appendix D. Write a report on your simulation results according to the Practice Example 6. Make conclusions about how multipulse laser heating would affect cancerous organelles in comparison to healthy organelles.

• 7.39. Perform multipulse heating simulations for normal and cancerous cell microtubules in cytoplasm by using thermal data from Tables 6.1 to 6.5 and the Maple code in Appendix D. Write a report on your simulation results according to the Practice Example 6. Make conclusions about how multipulse laser heating would affect cancerous organelles in comparison to healthy organelles.

• 7.40. Perform multipulse heating simulations for normal and cancerous cell ribosomes in cytoplasm by using thermal data from Tables 6.1 to 6.5 and the Maple code in Appendix D. Write a report on your simulation results according to the Practice Example 6. Make conclusions about how multipulse laser heating would affect cancerous organelles in comparison to healthy organelles.

• 7.41. Perform multipulse heating simulations for normal and cancerous cell cytoskeleton in cytoplasm by using thermal data from Tables 6.1 to 6.5 and the Maple code in Appendix D. Write a report on your simulation results according to the Practice Example 6. Make conclusions about how multipulse laser heating would affect cancerous organelles in comparison to healthy organelles.

7.2.3 Section 7.3: X-Ray and RF Heating of Nanoparticles

• 7.42. What are the properties of ideal radiation for nanophotodynamic therapy?

• 7.43. What parts of the electromagnetic spectrum satisfy the requirements of ideal radiation for nanophotodynamic therapy?

• 7.44. True or false? Short X-rays and long RF waves are universal tools for nanoparticle activation.

• 7.45. True or false? A surface plasmon resonance is observed in the visible and infrared range of spectrum.

• 7.46. True or false? Visible light has deep penetration into soft biological tissue.

• 7.47. List three main advantages of using X-rays to power photothermal therapies.

• 7.48. True or false? X-rays have low energy of individual photons.

• 7.49. What are therapeutic effects of X-ray-activated nanoparticles?

• 7.50. Select one or more. Therapeutic effects of the localized activation of nanoparticles by X-ray radiation can be achieved by:

  • (a) Surface plasmon resonance

  • (b) Heat generation

  • (c) Photoelectric effect

  • (d) Compton effect

  • (e) Thermionic emission

  • (f) Shock-wave generation

  • (g) Sound production

  • (h) All of the above

  • (i) None of the above

• 7.51 What improvements can nanoparticles bring to traditional X-ray radiation therapy?

• 7.52 True or false? Gold nanoparticles can dramatically reduce the therapeutic doses and exposure of X-ray radiation in cancer treatments.

• 7.53 True or false? The one-temperature model is designed for a monochromatic light source.

• 7.54 Select one or more. The output from most medical diagnostic X-ray devices has a:

  • (a) Narrow spectrum of photon energies

  • (b) Monochromatic radiation

  • (c) Wide spectrum of photon energies

  • (d) Polyenergetic beam

  • (e) Monoenergetic beam

  • (f) All of the above

  • (g) None of the above

• 7.55 What is an effective intensity-absorption efficiency?

• 7.56 What is the X-ray exposure range for heating a 50-nm gold nanoparticle?

• 7.57 What is the X-ray exposure range for a typical chest X-ray?

• 7.58 Select one or more. The exposure range for standard X-ray computed tomography scans is:

  • (a) 1.33–16. 81 mR/mA

  • (b) 6–25 mrem

  • (c) 300–2700 mrem

  • (d) All of the above

  • (e) None of the above

• 7.59 Select one or more. Incorporation of nanoparticles into cancer cells leads to synergistic effects like:

  • (a) Localized heating

  • (b) Photoelectron emission

  • (c) Thermionic emission

  • (d) Producing free radicals

  • (e) All of the above

  • (f) None of the above

• 7.60 True or false? Charged particles as well as free radicals are capable of repairing the DNA of cancer cells through direct or indirect actions.

• 7.61 What is the frequency range of RF waves?

• 7.62 True or false? The human body has a negligible absorption of RF waves.

• 7.63 Describe a major concept of the heating kinetics of nanoparticles.

• 7.64 True or false? All of the metals have the same heating kinetics and almost identical time–temperature profiles for the same conditions of RF heating.

• 7.65 True or false? A heating of different dielectric nanoparticles has similar time–temperature curves for the same conditions of RF heating.

• 7.66 Describe the single-pulse temperature graphs for carbon nanoparticles of various sizes.

• 7.67 True or false? The cooling rate of carbon nanoparticles doesn’t depend on the nanoparticle size.

• 7.68 Explain why dielectric materials show the heat accumulation effect when using a multipulse mode of heating.

• 7.69 True or false? Dielectric nanoparticles have much higher values of specific heat than metal ones.

• 7.70 True or false? The maximum temperature of the nanoparticle is reached after degradation of the heating radiation pulse.

• 7.71 True or false? During the pulse lifetime, the transfer of heat from the nanoparticles into the surrounding medium is slight, and the particles rapidly reach the maximum temperature.