NIST recently has released a SiNP reference material RM8027 that consists of five hermetically sealed pre-scored glass ampoules, each containing nominally 1 ml of cyclohexane-stabilized SiNPs suspended in toluene. The suspension contains particles (monomers) and a small percentage of clusters of primary particles. Biomolecular studies typically necessitate the water-dispersable NPs. This document describes a procedure of Reference Material 8027 reconstitution into aqueous solvents using UV- assisted hydrosilylation and phase-transfer with triblock copolymer Pluronic F127. Hydrosilylation method allows to exchange of the hydrophobic surface coating with positively (amine) or negatively (carboxyl) charged moieties, rendering SiNPs water soluble. The triblock copolymer phase transfer results in incorporation of the hydrophobic core into the hydrophobic NP shell, exposing the hydrophilic polyethylene oxide chain resulting in water solubility. Appendix contains reconstituted particle size measurements using dynamic light scattering, surface charge using zeta potential measurements and optical properties (UV-VIS absorbance and photoluminescence).
Special Publication (NIST SP) - 1200-12
Silicon nanoparticle, aqueous solvent, hydrosilylation, allylamine, pluronic, acrylic acid