Thermo-Responsive Hydrogel-Coated Gold Nanoshells for In Vivo Drug Delivery
نویسنده
چکیده
This paper describes the preparation and characterization of a new type of composite nanoparticle, where the structure consists of a nontoxic hydrogel polymer network that encapsulates a gold shell/silica core. These composite nanoparticles are being developed as photothermally responsive drug-delivery vehicles that undergo structural changes slightly above physiological temperature. A unique property of these nanoparticles is that the hydrogel coatings can be collapsed by exposure to light via excitation of the strong plasmon resonance of the gold shell/silica core; this excitation provides a ready source of heat to the system. Furthermore, the gold nanoshell (GNS) cores were designed to absorb light at near-infrared wavelengths (800–1200 nm), which can pass readily through tissue and water. The thermo-responsive hydrogel coatings were prepared by free radical polymerization of a selected mixture of N-isoproprylacrylamide (NIPAM) and acrylic acid (AAc) in the presence of the GNS core particles. The resultant composite particles were characterized structurally and compositionally by FE-SEM, TEM, and EDX, respectively. UV-vis spectroscopy was used to characterize the optical properties, and DLS was used to determine the average diameter as a function of temperature. As a whole, the results presented here demonstrate that these composite nanoparticles can be reliably prepared and characterized; moreover, their systematic responses to variations in temperature are consistent with their intended use as discrete nanoscale drug-delivery vehicles.
منابع مشابه
Hydrogel-Coated Near Infrared Absorbing Nanoshells as Light-Responsive Drug Delivery Vehicles
Nanoparticle drug delivery carriers that can modulate drug release based on an exogenous signal, such as light, are of great interest, especially for improving cancer therapy. A light-activated delivery vehicle was fabricated by synthesizing a thin, thermally responsive poly(N-isopropylacrylamide-co-acrylamide) hydrogel coating directly onto the surfaces of individual near-infrared (NIR) absorb...
متن کاملDiscrete thermally responsive hydrogel-coated gold nanoparticles for use as drug-delivery vehicles
This report describes the development of optically responsive gold nanoparticles ( 60 nm in diameter) coated with a thermally responsive biocompatible hydrogel overlayer (20–90 nm thick). The hydrogel consists of a mixture of N-isoproprylacrylamide and acrylic acid; this copolymer can be tailored to exhibit a lower critical solution temperature (LCST) slightly above physiological temperature. W...
متن کاملThermo- and pH-responsive hydrogel-coated gold nanoparticles prepared from rationally designed surface-confined initiators
Gold nanoparticles (*40 nm in diameter) were encapsulated by a hydrogel overlayer generated by the free radical polymerization of N-isopropylacrylamide-co-acrylic acid (NIPAM-co-AA), which was promoted by a specifically designed radical initiator covalently anchored to the surface of the gold core. The size and morphology of the shell/core nanoparticles were characterized by scanning electron m...
متن کاملGold nanorods coated with a thermo-responsive poly(ethylene glycol)-b-poly(N-vinylcaprolactam) corona as drug delivery systems for remotely near infrared-triggered release
متن کامل
Loratadine- Loaded Thermoresponsive Hydogel : Characterization and Ex-vivo Rabbit Cornea Permeability Studies
Poor bioavailability of ophthalmic drops is mainly due to drainage through the nasal-lacrimal duct and a very low permeability through corneal epithelium. The aim of our study was to prepare and characterize an ocular hydrogel of loratadine, as an example of a lipophilic drug, to increase drug concentration and residence time at the site of action in the eye. In this study,a 23full factorial de...
متن کامل