Microwave-Assisted Synthesis of Biofunctional and Fluorescent Silicon Nanoparticles Using Proteins as Hydrophilic Ligands

Institute of Functional Nano & Soft Materials, FUNSOM and Jiangsu Key Laboratory for Carbon-based Functional Materials & Devices, Soochow University, Suzhou 215123, China.
Angewandte Chemie International Edition (Impact Factor: 11.26). 08/2012; 51(34):8485-9. DOI: 10.1002/anie.201202085
Source: PubMed


Protective shell: A microwave-assisted method allows rapid production of biofunctional and fluorescent silicon nanoparticles (SiNPs), which can be used for cell labeling. Such SiNPs feature excellent aqueous dispersibility, are strongly fluorescent, storable, photostable, stable at different pH values, and biocompatible. The method opens new avenues for designing multifunctional SiNPs and related silicon nanostructures.

101 Reads
  • [Show abstract] [Hide abstract]
    ABSTRACT: Quantum confined silicon nanocrystals (Si-ncs) exhibit intriguing properties due to silicon's indirect bandgap and their highly reactive surfaces. In particular the interplay of quantum confinement with surface effects reveals a complex scenario, which can complicate the interpretation of Si-nc properties and prediction of their corresponding behaviour. At the same time, the complexity and interplay of the different mechanisms in Si-ncs offer great opportunities with characteristics that may not be achievable with other nano-systems. In this context, a variety of carefully surface-engineered Si-ncs are highly desirable both for improving our understanding of Si-nc photo-physics and for their successful integration in application devices. Here we firstly highlight a selection of theoretical efforts and experimental surface engineering approaches and secondly we focus on recent surface engineering results that have utilized novel plasma-liquid interactions.
    No preview · Article · Jan 2013 · Nanoscale
  • [Show abstract] [Hide abstract]
    ABSTRACT: In this paper, we report on the preparation of decyl-modified silicon nanoparticles (decyl-SiNPs) and their encapsulation into silica nanoparticles (NPs). The decyl-SiNPs were obtained by the photoinduced hydrosilylation of hydride-terminated SiNPs (H-SiNPs), liberated from porous silicon (pSi), followed by encapsulation into silica NPs (SiNPs@SiO2) via the Stöber process. Two different sized SiNPs@SiO2 were synthesized, 15 and 25 nm in diameter. Their composition, size, shape, luminescence properties, colloidal and spectral stability in different environments and under ultraviolet (UV) light irradiation were studied by various techniques, including Fourier transform infrared spectroscopy (FT-IR), transmission electron microscopy (TEM), UV-vis absorption, dynamic light scattering (DLS) and photoluminescence (PL) spectroscopy. The results indicate that the SiO2 coating renders the hydrophobic alkylated SiNPs dispersible in water, but leads to some loss of their PL intensity. The SiNPs@SiO2 NPs exhibit a wide pH stability, but show a pronounced PL degradation due to a blinking behavior. The photobleaching process could be partially suppressed by increasing the SiO2 outer shell thickness. Some investigations were made on the luminescence quenching, spectral shift and photobleaching. For potential bioapplications, the SiNPs@SiO2 NPs were modified with aminopropyl groups under acidic conditions without obvious luminescence loss and further conjugated with folic acid (FA). Considering the features of red-emission, versatile SiO2 surface chemistry and controlled size, the present SiNPs@SiO2 nanocomposites may find wide applications in cellular fluorescence labeling and the preparation of light-emitting devices.
    No preview · Article · Aug 2013
  • [Show abstract] [Hide abstract]
    ABSTRACT: Stem-loop oligonucleotides tagged with organic dyes are employed as capture and reporter probes in a molecular beacon-based signal-off surface- enhanced Raman scattering (SERS) strategy. DNA strands are immobilized on a gold nanoparticle-decorated silicon nanowire array (AuNPs@SiNWAr). DNA with a concentration down to ≈10 fM is detected under irradiation from a low-power laser, which is better than or comparable to that detected by signal-on SERS methods. The signal-off strategy allows identification of single-base mismatches and detection of multiplexed DNA.
    No preview · Article · Aug 2013 · Small
Show more