Gold nanoparticles as radiosensitizer for radiotherapy and diagnosis of COVID-19: A review

ABSTRACT

Radiotherapy is an established therapy in cancer treatments that uses energy deposition directly into tumor tissue. With the introduction of radiosensitizers, invasive surgical and chemotherapy techniques can be avoided. Radiosensitizers with a high-Z base such as gold nanoparticles (AuNPs) are promising candidates for catalyzing tumor injury and simultaneously enabling tracking to be done inside the organ via a computed tomography scan or other diagnostic imaging. It has been documented that AuNP possess biocompatibility characteristics as well as nontoxic properties depending on the size of the application and the applied coating. Radiosensitizers can increase tumor targeting, thus providing more specific destruction than conventional techniques while minimizing damage to surrounding healthy tissues. This review focuses on the special properties of AuNP in assisting radiotherapy as a radiosensitizing agent. Important parameters for AuNP’s optimization are listed to offer general guidelines for which the specifications of AuNP should be directed. In addition, the mechanism of AuNP radiosensitization in physical, chemical, and biological phases is discussed. A list of in vitro and in vivo testing and current clinical trials of AuNP are presented in sequence. Finally, the utilization of AuNP for diagnosing and combating the COVID-19 pandemic is discussed for future outbreak surveillance and intervention.

KEYWORDS:

• Cancer
• gold
• nanoparticles
• radiotherapy
• radiosensitizer

Acknowledgments

The authors acknowledge the FRGS/1/2019/STG02/UKM/02/6 from the Malaysia Ministry of Higher Education for the granted fund, and extend appreciation to the Nuclear Technology Research Centre, Faculty of Science and Technology, Universiti Kebangsaan Malaysia (UKM).

Disclosure statement

No potential conflict of interest was reported by the author(s).

Author contributions

Abdul Khaliq Mokhtar – conceptualization, investigation, creating research design, writing original draft, and visualization; Norsyahidah Mohd Hidzir – supervision, conceptualization, creating research design, writing-review and editing, and funding acquisition; Faizal Mohamed – supervision, conceptualization, editing and revision; Irman Abdul Rahman – supervision, conceptualization, and revision; Syazwani Mohd Fadzil – writing-review and revision; Afifah Mardhiah Mohamed Radzi – revision and redesign Figure 1 and Nur Ain Mohd Radzali – writing-review and revision.

Additional information

Funding

This work was supported by the Malaysia Ministry of Higher Education under Grant [FRGS/1/2019/STG02/UKM/02/6].