Synthesis of Ultrastable Gold Nanoparticles as a New Drug Delivery System

Abstract

Nanotechnologies are increasingly being developed for medical purposes. However, these nanomaterials require ultrastability for better control of their pharmacokinetics. The present study describes three types of ultrastable gold nanoparticles stabilized by thiolated polyethylene glycol groups remaining intact when subjected to some of the harshest conditions described thus far in the literature, such as autoclave sterilization, heat and freeze-drying cycles, salts exposure, and ultracentrifugation. Their stability is characterized by transmission electron microscopy, UV-visible spectroscopy, and dynamic light scattering. For comparison purposes, two conventional nanoparticle types were used to assess their colloidal stability under all conditions. The ability of ultrastable gold nanoparticles to encapsulate bimatoprost, a drug for glaucoma treatment, is demonstrated. MTS assays on human corneal epithelial cells is assessed without changing cell viability. The impact of ultrastable gold nanoparticles on wound healing dynamics is assessed on tissue engineered corneas. These results highlight the potential of ultrastable gold nanoparticles as a drug delivery system in ocular therapy.

Epigallocatechin-3-Gallate-Loaded Gold Nanoparticles: Preparation and Evaluation of Anticancer Efficacy in Ehrlich Tumor-Bearing Mice

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Fabrication and Characterization of Chitosan/Poly(Lactic-Co-glycolic Acid) Core-Shell Nanoparticles by Coaxial Electrospray Technology for Dual Delivery of Natamycin and Clotrimazole

“…Following the rapid development of nanomaterials, many researches have focused on the use of nanomaterials-based drug delivery systems in order to increase the bioavailability, prolong residence time, and reduce the side effects of various drugs ( Yamada, 2014 ). According to the existing literature, more and more materials have been extensively studied and successfully designed for topical ocular delivery, such as poly(glycerol sebacate) ( Chegini et al, 2019 ), eudragit ( Rathod et al, 2017 ), and gold ( Masse et al, 2019 ). However, a major challenge with these nanomaterial-based drug delivery systems is that the materials have unknown or objectionable toxicity profiles and are not approved by the regulatory authorities.…”

Methods for Reducing the Toxicity of Metal and Metal Oxide NPs as Biomedicine

“…After several tests, such as freeze drying, heating, ultracentrifugation, and autoclaving, the high stability of nanoparticles was confirmed. In addition, ultra-stable nanoparticles did not show any signs of cytotoxicity [57].…”