Plasmonic Effect of Gold-Patchy Silica Nanoparticles on Green Light-Photopolymerizable Dental Resin

Abstract

A low ratio of polymerization is a major problem in resin-based composites. In this paper, the plasmonic effect of gold-covered silica nanoparticles on the physicochemical and mechanical properties of bisphenol A diglycidyl dimethacrylate (Bis-GMA), triethylene glycol dimethacrylate (TEGDMA) and urethane dimethacrylate (UDMA) green light-photopolymerizable dental resin was investigated at an intensity of 1.4 mW/cm2 for 40 s. Transmission electron microscopy (TEM) showed silica of about 350 nm covered with 12–15 nm gold nanoparticles (Au NPs) at 100% nominal coverage. Five different concentrations of bare and patchy silica particles were used; in the latter composite, the calculated Au wt% were 0.0052 wt%, 0.0104 wt%, 0.0208 wt%, 0.04160 wt%, and 0.0823 wt%. The plasmon peak of patchy silica-filled nanocomposite overlapped with the absorption of Irgacure 784 photoinitiator and green LED light emission peak. The effect of plasmon-enhanced polymerization achieved with green light illumination was analyzed using diametral tensile strength (DTS), differential scanning calorimetry (DSC), surface plasmon resonance imaging (SPRi), and degree of conversion (DC) based on Raman spectroscopy. The values of the Au NP with 0.0208 wt% was found to be maximum in all the measured data. Based on our result, it can be concluded that the application of patchy silica particles in dental resin can improve the polymerization ratio and the mechanical parameters of the composite.

Nanochemistry of gold: from surface engineering to dental healthcare applications

“…For GNSs to maintain a stable dispersion in water or saline buffers when utilized in living systems, they necessitate a biocompatible and hydrophilic surface. 95 Hydrophilic surface-reactive molecules, including thiolates and amine groups, 96 polymeric materials (such as chitosan and poly(ethylene glycol)), 97 as well as inorganic materials like silica and organically modified silica, 98 are commonly used for GNSs functionalization. These ligands, whether inherently part of the molecules or incorporated without altering their inherent properties, form essential bonds with GNS surfaces, specifically Au–S or Au–N bonds, ensuring the required biocompatibility and hydrophilicity necessary for GNS stability in aqueous or saline environments within living systems.…”

Review of Gold Nanoparticles in Surface Plasmon-Coupled Emission Technology: Effect of Shape, Hollow Nanostructures, Nano-Assembly, Metal–Dielectric and Heterometallic Nanohybrids

“…Although different types of plasmonic materials have been explored globally, AuNPs are considerably distinct and stand out on account of several advantages such as (i) overarching chemical and physical stability, (ii) feasibility for bio-functionalization, (iii) copious electron density (≈5.90 × 10 16 m −3 ), (iv) excellent photo-plasmonic response in the visible and NIR region and (v) biocompatibility, to name a few [ 55 , 56 , 57 , 58 , 59 , 60 ]. The SPR characteristics of AuNPs are widely used in research fields encompassing plasmon-enhanced fluorescence (PEF), heat generation, photocatalysis, energy research, non-linear optics and Raman spectroscopy to name a few [ 61 , 62 , 63 , 64 , 65 , 66 ]. Moreover, the surface-enhanced spectroscopic and imaging technologies have utilized AuNPs extensively in fields including but not limited to surface-enhanced Raman spectroscopy (SERS), surface-enhanced fluorescence (SEF), surface-enhanced infrared absorption (SEIRA) spectroscopy and surface plasmon-coupled emission (SPCE), to name a few [ 55 , 67 , 68 , 69 , 70 , 71 ].…”