Cancer Treatment Using Different Shapes of Gold-Based Nanomaterials in Combination with Conventional Physical Techniques

Abstract

The conventional methods of cancer treatment and diagnosis, such as radiotherapy, chemotherapy, and computed tomography, have developed a great deal. However, the effectiveness of such methods is limited to the possible failure or collateral effects on the patients. In recent years, nanoscale materials have been studied in the field of medical physics to develop increasingly efficient methods to treat diseases. Gold nanoparticles (AuNPs), thanks to their unique physicochemical and optical properties, were introduced to medicine to promote highly effective treatments. Several studies have confirmed the advantages of AuNPs such as their biocompatibility and the possibility to tune their shapes and sizes or modify their surfaces using different chemical compounds. In this review, the main properties of AuNPs are analyzed, with particular focus on star-shaped AuNPs. In addition, the main methods of tumor treatment and diagnosis involving AuNPs are reviewed.

Keywords: cancer; diagnostics; gold nanoparticles; medical physics; nanomedicine; nanostars; therapy.

Figure 1

AuNPs atoms number as a function of surface area and size [17].

Figure 2

LSPR effect: plasmon oscillation for a AuNP [20].

Figure 3

Different sizes of spherical AuNPs correspond to different color solutions. Reprinted (adapted) with permission from [24]. Copyright 2007, American Chemical Society.

Figure 4

Cartesian graph of the different values of the melting point vs. AuNPs’ dimensions [17].

Figure 5

Different AuNP shapes [28].

Figure 6

AuNSs images acquired by Transmission Electron Microscopy (TEM) at different magnifications: 50 nm scale bar (a) and 500 nm scale bar (b) [30].

Figure 7

Three possible radiotherapy approaches: (1) External beam radiation therapy; (2) brachytherapy; (3) AuNPs-enhanced radiation therapy. Reprinted (adapted) with permission from [58], John Wiley and Sons.

Figure 8

Surface plasmon absorption spectra for different nanorods’ aspect ratios. Reprinted (adapted) with permission from [97], Copyright 2006 American Chemical Society.

Figure 9

Reaction mechanism of PDT [113].

Figure 10

PA images of EGFR+ A431 cells labeled with 5 nm MAPS for different periods of time. PA images of 40 nm MAPS for comparison [142].

Figure 11

PA images of the two groups of mice after injection of (A) AuNSs and (B) RBCm-AuNSs. The images cover different periods of time from 0 h until 48 h [143].

Figure 12

SPECT/CT images of mice injected with ^99mTc-Au-Ac-PENPs at (a) 0.5 h, (b) 1 h and (c) 2 h; SPECT/CT images of mice injected with ^99mTc-Au-Gly-PENPs at (d) 0.5 h, (e) 1 h and (f) 2 h [152].

Figure 13

SPECT images of mice treated with (A) BmK CT-Au PENPs-¹³¹I and (B) Au PENPs, respectively, at different time points post-injection. The tumor site is highlighted by white circle [154].

Figure 14

(a) CT images for different GNS-FA concentration; (b) Hounsfield values dependent on the AuNSs concentrations. Reprinted (adapted) with permission from [167], Copyright 2021 American Chemical Society.

Figure 15

(A) PA images with Au nanorods@PDA as exogenous contrast; (B) PA images with Au nanorods as exogenous contrast. Reprinted (adapted) with permission from [168]. Copyright 2021 American Chemical Society.