Graphene Oxide-Gold Nanorods Nanocomposite-Porphyrin Conjugate as Promising Tool for Cancer Phototherapy Performance

Abstract

The cancer mortality rate has increased, and conventional cancer treatments are known for having many side effects. Therefore, it is imperative to find a new therapeutic agent or modify the existing therapeutic agents for better performance and efficiency. Herein, a synergetic phototherapeutic agent based on a combination of photothermal and photodynamic therapy is proposed. The phototherapeutic agent consists of water-soluble cationic porphyrin (5,10,15,20-tetrakis(N-methylpyridinium-3-yl)porphyrin, TMePyP), and gold nanorods (AuNRs) anchored on graphene-oxide (GO) sheet. The TMePyP was initially synthesized by Adler method, followed by methylation, while GO and AuNRs were synthesized using Hummer’s and seed-mediated methods, respectively. The structural and optical properties of TMePyP were confirmed using UV-Vis, zeta analyzer, PL, FTIR and NMR. The formation of both GO and AuNRs was confirmed by UV-Vis-NIR, FTIR, TEM and zeta analyzer. TMePyP and AuNRs were anchored on GO to form GO@AuNRs-TMePyP nanocomposite. The as-synthesized nanocomposite was stable in RPMI and PBS medium, and, on irradiation, produced high heat than the bare AuNRs, with high photothermal efficiency. In addition, the nanocomposite produced higher singlet oxygen than TMePyP with high biocompatibility in the absence of light. These results indicated that the as-synthesized nanocomposite is a promising dual photodynamic and photothermal agent for cancer therapy.

Carbonaceous Nanomaterials for Phototherapy of Cancer

“…Based on these findings, the synthesized nanostructure has tremendous potential as a dual photothermal and photodynamic agent for cancer treatment. 122 nGO is a graphene oxidative derivative with a 2D carbon layer as well as a large surface area, which is particularly gaining attraction due to its unique structure. 123 NIR absorption is a property of nGO due to its oxygen functional groups like epoxy, carboxyl, and hydroxyl.…”

Thermal and Medium Stability Study of Polyvidone-Modified Graphene Oxide-Coated Gold Nanorods with High Photothermal Efficiency

“…The FTIR spectrum of AuNRs shows characteristic peaks of CTAB with long C-H asymmetric and symmetric stretching vibrations at 2916 and 2849 cm −1 , respectively (Figure 2D). The corresponding C-H bending vibrations with the splitting is at 1473 and 1463 cm −1 , while the C-H (CH 3 −N + ) asymmetric and symmetric bending vibrations are at 1487 and 1431 cm −1 , respectively (Figure 2D) [20]. The GO spectrum shows O-H stretching at 3416 cm −1 , C=O vibration shoulder peak at 1761 cm −1 , aromatic C=C stretching at 1654 cm −1 , and epoxy and carboxyl vibrations between 1230 to 1320 cm −1 (Figure 2A) [36,41].…”

“…The thermocouple in Figure 5A shows that the mGO@AuNRs have the highest temperature change of 34.8 • C, followed by GO@AuNRs (28.4 • C), bare AuNRs (25.1 • C), PVP@AuNRs (22.6 • C), and lastly deionised water (DW, 12 • C). The highest temperatures of mGO@AuNRs and GO@AuNRs were due to the enriched photon absorption caused by GO sheets when irradiated with a laser [15,20,45]. The thermal camera images in Figure 5B show the actual temperature captured at 10 min irradiation for all the samples.…”

“…Currently, different coating materials, such as polymers (polyvinylpyrrolidone (PVP)) [6][7][8][9][10][11], biomolecules [12][13][14], and graphene-based materials (graphene oxide (GO)) [10,[15][16][17][18][19], have been employed to reduce the toxicity of AuNRs. Among these materials, graphene-based AuNRs has been shown to be more effective as they minimise toxicity and simultaneously increase photothermal efficiency, in particular, GO [10,[15][16][17][18]20].…”

“…GO is an exfoliated graphene sheet with carbon-bonded oxygen functional groups, such as epoxy, hydroxyl, carbonyl, and carboxylic [2,[19][20][21][22]. It is biocompatible and easy to…”