Metal Nanostructures with Magnetic and Biodegradable Properties for Medical Applications

Abstract

Gold nanoparticles (AuNPs) were synthesized by reduction of HAuCl4 with NaBH4 or l-ascorbic acid and they were stabilized with cysteine, cysteamine and a thiol-capped PEG. A nanocomposite was prepared by the addition of polylactic acid (PLA) acetone solutions to aqueous AuNP dispersions, resulting in PLAs enclosing AuNPs. Superparamagnetic iron oxide nanoparticles (SPION) modified with Au on the surface (SPION@Au NP) were synthesized. SPIONs were prepared by using iron-oleate as a precursor or by co-precipitation of ferrous and ferric chlorides in alkaline solution and, then used for seed-mediated growth of gold layers on their surfaces. The various nanoparticles were characterized by using UV-Vis spectroscopy, electron spectroscopy imaging/transmission electron microscopy (ESI/TEM) and by thermogravimetric analysis (TGA). The magnetic products were tested in a magnetic resonance imaging (MRI) scanner of high clinical field with results that indicate their promising utilization as contrast agents for MRI analysis

Sensor for Prednisolone Detection in Sports Doping

“…The precursor was ultrasonically added to 1 ml of L-cysteine hydrochloride monohydrate and 1 ml of cysteamine aqueous solution for the production of Au NPs. 13 1 ml of 10 mM NaBH 4 aqueous solution was gradually added to the solution after 20 minutes of ultrasonication. The resulting mixture was then allowed to react for 120 minutes.…”

Insulin administration: present strategies and future directions for a noninvasive (possibly more physiological) delivery

“…To use the AuNPs in vivo for a long retention time avoiding the action of the reticular endothelial system, their surface can be modified with antibiofouling agents, such as polyethylene glycol, and more stable bonds can be created by self-assembling molecules with thiol groups onto gold surfaces. 71 …”

Polymethylolacrylamide/AuNPs Nanocomposites: Electrochemical Synthesis and Functional Characteristics

“…Nanoparticles of Cu [13][14][15], Ni, Co, and Fe [5] and metal oxides (SnO 2 , Fe 3 O 4 ) [16,17] are used as fillers of a polymer matrix. However, the most interesting materials here are nanocomposite materials with the inclusion of noble metal particles: Ag [18][19][20], Au [6,[21][22][23][24][25][26][27][28][29][30], Pt [30][31][32], and Pd [19]. Most published studies on this subject are devoted to the production and application of hybrid materials containing AuNPs.…”

“…To create polymer/metal nanoparticle hybrid materials, the following methods are traditionally used: (1) separate synthesis of a polymer and metal nanoparticles, followed by their inclusion into the polymer matrix; (2) synthesis of a polymer, its impregnation with metal salts with subsequent reduction to metal by chemical [3,14,15,[25][26][27][28][29], physical [22], or electrochemical [4,13,23,30,31] methods; (3) synthesis of metal nanoparticles and their addition to a monomer composition for polymerization; (4) synthesis of a polymer with subsequent deposition of a metal on its surface. All of these technologies are complex, multi-stage (≥3 stages), and time-consuming.…”