All-inorganic water-dispersible silicon quantum dots: highly efficient near-infrared luminescence in a wide pH range

Abstract

We report a novel method to prepare silicon quantum dots (Si-QDs) having excellent stability in water without organic-ligands by simultaneously doping phosphorus and boron. The codoped Si-QDs in water exhibit bright size-tunable luminescence in a biological window. The luminescence of codoped Si-QDs is very stable under continuous photoexcitation in water.

Cytotoxicity assessment of functionalized CdSe, CdTe and InP quantum dots in two human cancer cell models

“…For instance, our group has demonstrated the preparation of silicon (Si) QDs for bioimaging applications and these particles possess very low toxicity [30,31]. Such result suggests that this material will be a strong candidate in replacing heavy-metal based QDs for future clinical applications [32,33]. Applying surface coating on QDs is another useful strategy to prevent the breakdown of the nanocrystals.…”

Plasmon-Enhanced Emission Rate of Silicon Nanocrystals in Gold Nanorod Composites

“…Colloidal Si NCs prepared in this work are negatively charged (-25 mV in water at pH 7) 30 and Au nanorods are positively charged (+35 mV in water at pH 7). Therefore, by mixing 25 µL of Si NC solution (1×10 16 NCs/mL) with 1.5 mL of concentrated Au nanorod solution (1.7×10 10 nanorods/mL) for 2 days, NCs attach to the surface of the nanorods by electrostatic interaction.…”

DNA assembly of silicon quantum dots/gold nanoparticle nanocomposites

“…32 The codoped Si-QDs have negative surface potential and are dispersible in water almost perfectly without organic ligands. 33 They exhibit size tunable and stable PL in the NIR range in water. 33 First, we functionalize the surface by three types of silane coupling agents via the surface Si-OH bonds and study the influence on the solution dispersibility and the PL properties.…”

“…33 They exhibit size tunable and stable PL in the NIR range in water. 33 First, we functionalize the surface by three types of silane coupling agents via the surface Si-OH bonds and study the influence on the solution dispersibility and the PL properties. We then conjugate Si-QDs and singlestranded DNA (ssDNA) and demonstrate the formation of nanocomposites composed of Si-QDs and gold (Au) nanoparticles (NPs) by DNA hybridization.…”