Development of porous silicon‐coated gold nanoparticles as potential theragnostic material

Abstract

Gold nanoparticles (AuNPs) have been used widely as multifunctional materials for several biomedical applications due to their attractive characteristics. However, toxicity and aggregation of AuNPs are critical issues, and methods of effective surface modification are required to overcome these problems. In this study, porous silicon-coated gold nanoparticles (AuNP@pSi) were fabricated as a hybrid nanocomposite capable of surface-enhanced Raman scattering (SERS)sensing and drug carrier. First, size-controlled AuNPs were coated with a silica nano-shell, and the resulting silica layers were converted to porous silicon through magnesiothermic reduction. Overall results suggest that AuNP@pSi can be exploited as a SERS probe with efficient Raman signal improvement of benzenethiol as well as a drug carrier based on its high surface area (113.7 m 2 g À1 ) and porosity (13.38 nm, 0.3805 cm 3 g À1 ). Since the porous silicon possibly can serve as magnetic resonance imaging probes with DNP technology, this hybrid platform potentially can be utilized as powerful material capable of theragnosis system.

Background free in vivo29Si MR imaging with hyperpolarized PEGylated silicon nanoparticles

“…Furthermore, PEGylated silicon nanoparticles will find useful applications, such as imparting porosity and partnering with other nanoparticles for dual imaging and constructing theragnostic systems. 37…”

Development of porous calcite structure from industrial waste for efficient adsorbent for protein

“…Preparation of calcite particles in nanometer scale through either top-down or bottom-up methods is a possible approach enhance specific surface area; however, thus prepared nanoparticles often forms strong aggregates to reduce surface area. [16][17][18][19] Introduction of porosity in calcite would be an alternative solution to increase protein affinity. Li et al prepared porous calcite utilizing gelatin template.…”

“…To overcome the limitation of calcite in protein adsorption capacity, the best way is to increase the specific surface area dramatically or to develop porous structure in calcite materials. Preparation of calcite particles in nanometer scale through either top‐down or bottom‐up methods is a possible approach enhance specific surface area; however, thus prepared nanoparticles often forms strong aggregates to reduce surface area 16–19 . Introduction of porosity in calcite would be an alternative solution to increase protein affinity.…”

Synthesis of ultra‐small gold nanorods: Effect of reducing agent on reaction rate control

“…This is used in bioimaging, biosensing, and surface-enhanced Raman scattering (SERS) because of strong LSPR properties in the near-IR region. 6,[8][9][10][11][12][13][14][15] Gold nanorods are also attracting attention in nanomedical fields such as photothermal therapy, 16,17 photoacoustic imaging, [18][19][20] and drug delivery. 21,22 This attention results from their favorable characteristics of strongly absorbing and scattering light in the NIR region as well as stability, 23 biocompatibility, 24 and ease of surface modification.…”