Stable Encapsulation of Quantum Dot Barcodes with Silica Shells

Quantum dot‐doped mesoporous microbeads (QDMMs) are encapsulated with silica shells for enhanced chemical stability. The results show that a microemulsion procedure is highly efficient in coating QDMMs with polyvinyl alcohol (PVA), which is important in the subsequent deposition of a silica shell. Incorporation of fluorescent silane precursors allows direct observation of silica shells by fluorescence microscopy. The resulting silica‐coated QDMMs (QDMM@SiO2) exhibit remarkable stability against solvent‐induced QD leaching and chemical‐induced fluorescence quenching compared with the uncoated QDMMs. Further development of this technology such as optimization of silica shell thickness, surface modification with non‐fouling polymers, and conjugation with biomolecular probes will enable clinical translation of the optical barcoding technology for highly multiplexed detection and screening of genes and proteins.

[1]  Xiaohu Gao,et al.  Multifunctional Quantum Dots for Personalized Medicine. , 2009, Nano today.

[2]  D. Brühwiler,et al.  Accessibility of Amino Groups in Postsynthetically Modified Mesoporous Silica , 2009 .

[3]  Dean-Mo Liu,et al.  Surfactant‐Free, Self‐Assembled PVA‐Iron Oxide/Silica Core–Shell Nanocarriers for Highly Sensitive, Magnetically Controlled Drug Release and Ultrahigh Cancer Cell Uptake Efficiency , 2008 .

[4]  A. Meijerink,et al.  On the Incorporation Mechanism of Hydrophobic Quantum Dots in Silica Spheres by a Reverse Microemulsion Method , 2008 .

[5]  R. Westervelt,et al.  Incorporation of iron oxide nanoparticles and quantum dots into silica microspheres. , 2008, ACS nano.

[6]  M. Gundersen,et al.  pH-sensitive Photoluminescence of CdSe/ZnSe/ZnS Quantum Dots in Human Ovarian Cancer Cells. , 2007, The journal of physical chemistry. C, Nanomaterials and interfaces.

[7]  D. Brühwiler,et al.  Distribution of amino groups on a mesoporous silica surface after submonolayer deposition of aminopropylsilanes from an anhydrous liquid phase , 2007 .

[8]  Andreas Hofmann,et al.  A general method for the controlled embedding of nanoparticles in silica colloids. , 2006, Langmuir : the ACS journal of surfaces and colloids.

[9]  Shuming Nie,et al.  Multicolor quantum dots for molecular diagnostics of cancer , 2006, Expert review of molecular diagnostics.

[10]  Nikolai Gaponik,et al.  Comparative examination of the stability of semiconductor quantum dots in various biochemical buffers. , 2006, The journal of physical chemistry. B.

[11]  R. Jain,et al.  Incorporation of Luminescent Nanocrystals into Monodisperse Core–Shell Silica Microspheres , 2004 .

[12]  Shuming Nie,et al.  Quantum dot-encoded mesoporous beads with high brightness and uniformity: rapid readout using flow cytometry. , 2004, Analytical chemistry.

[13]  Shuming Nie,et al.  Doping Mesoporous Materials with Multicolor Quantum Dots , 2003 .

[14]  Christina Graf,et al.  A General Method To Coat Colloidal Particles with Silica , 2003 .

[15]  Shuming Nie,et al.  Quantum-dot nanocrystals for ultrasensitive biological labeling and multicolor optical encoding. , 2002, Journal of biomedical optics.

[16]  Matt Trau,et al.  Optical barcoding of colloidal suspensions: applications in genomics, proteomics and drug discovery. , 2002, Chemical communications.

[17]  Kevin Braeckmans,et al.  Encoding microcarriers: present and future technologies , 2002, Nature Reviews Drug Discovery.

[18]  S. Nie,et al.  Quantum-dot-tagged microbeads for multiplexed optical coding of biomolecules , 2001, Nature Biotechnology.

[19]  K. Suh,et al.  Monodisperse micron-sized macroporous poly(styrene-co-divinylbenzene) particles by seeded polymerization , 2001 .

[20]  Darryn Bryant,et al.  Toward larger chemical libraries: Encoding with fluorescent colloids in combinatorial chemistry , 2000 .

[21]  F. Steemers,et al.  Screening unlabeled DNA targets with randomly ordered fiber-optic gene arrays , 2000, Nature Biotechnology.

[22]  K. Unger,et al.  Tailored syntheses of nanostructured silicas: Control of particle morphology, particle size and pore size , 1998 .

[23]  D. Walt,et al.  A fiber-optic DNA biosensor microarray for the analysis of gene expression , 1996, Nature Biotechnology.

[24]  F. Švec,et al.  Fine control of the porous structure and chromatographic properties of monodisperse macroporous poly(styrene-co-divinylbenzene) beads prepared using polymer porogens , 1994 .

[25]  J. Vanderhoff,et al.  Synthesis and characterization of monodisperse porous polymer particles , 1992 .

[26]  Horst Weller,et al.  Photochemistry of colloidal semiconductors. 20. Surface modification and stability of strong luminescing CdS particles , 1987 .