Fast magnetic isolation of simple sequence repeat markers in microfluidic channels.

Simple sequence repeat (SSR) markers are widely used for genome mapping, genetic diversity characterization and medical diagnosis. The fast isolation by AFLP of sequence containing repeats (FIASCO) is a powerful method for SSR marker isolation, but it is laborious, costly, and time consuming and requires multiple rounds of washing. Here, we report a superparamagnetic bead (SPMB)-based FIASCO method in a magnetic field controllable microfluidic chip (MFCM-Chip).

Surface labeling of enveloped viruses assisted by host cells.

Labeling of virus opens new pathways for the understanding of viruses themselves and facilitates the utilization of viruses in modern biology, medicine, and materials. Based on the characteristic that viruses hijack their host cellular machineries to survive and reproduce themselves, a host-cell-assisted strategy is proposed to label enveloped viruses. By simply feeding Vero cells with commercial 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine-N-(cap biotinyl) (sodium salt) (Biotin-Cap-PE), we obtained biotinylated Vero cells whose membrane systems were modified with biotin.

One-to-one quantum dot-labeled single long DNA probes.

Quantum dots (QDs) have been received most attention due to their unique properties. Constructing QDs conjugated with certain number of biomolecules is considered as one of the most important research goals in nanobiotechnology. In this study, we report polymerase chain reaction (PCR) amplification of primer oligonucleotides bound to QDs, termed as QD-based PCR.

Direct fluorescence in situ hybridization (FISH) in Escherichia coli with a target-specific quantum dot-based molecular beacon.

Quantum dots (QDs) are inorganic fluorescent nanocrystals with excellent properties such as tunable emission spectra and photo-bleaching resistance compared with organic dyes, which make them appropriate for applications in molecular beacons. In this work, quantum dot-based molecular beacons (QD-based MBs) were fabricated to specifically detect β-lactamase genes located in pUC18 which were responsible for antibiotic resistance in bacteria Escherichia coli (E. coli) DH5α.

PEG-interspersed nitrilotriacetic acid-functionalized quantum dots for site-specific labeling of prion proteins expressed on cell surfaces.

A strategy has been put forward to fabricate PEG-interspersed nitrilotriacetic acid (NTA)-functionalized QDs by one-step self-assembly using a mixture of self-synthesized NTA-terminated amphiphilic polymer and 1,2-Distearoyl-sn-Glycero-3-Phosphoethanolamine-N-[Carboxy(Polyethylene Glycol)2000] (DSPE-PEG-COOH). The process was highly reproducible for facile functionalization of QDs via simultaneous self-assembly of biocompatible PEG molecules onto their surface. An optimized molar ratio of NTA-terminated amphiphilic polymer to DSPE-PEG-COOH was used to obtain NTA-functionalized QDs for site-specific labeling of prion proteins (PrP(C)) expressed on cell surfaces.

Clickable gold nanoparticles as the building block of nanobioprobes.

A new method of fabricating "clickable" gold nanoparticles that could be used as the building block of nanobioprobes was described. On the basis of a well-developed strategy of encapsulating hydrophobic nanoparticles with a layer of amphiphilic polymers, cheap, easily prepared graft polymer was used as a modifier to prepare monodisperse azide-functionalized gold nanoparticles (AuNPs), which showed good stability in physiological solution. By conjugation with alkyne functional horseradish peroxidase (HRP) via click chemistry under mild conditions, the azide-AuNPs have demonstrated their potential in the fabrication of stable, bioactive nanobioprobes.

Color-tunable fluorescent-magnetic core/shell multifunctional nanocrystals.

We have developed a convenient strategy for preparing color-tunable fluorescent-magnetic core/shell multifunctional nanocrystals, which exhibit excellent photoluminescence (PL) properties (fluorescing tunably from 550 nm to 630 nm by modifying the shell thickness) and ferromagnetic material properties (a magnetization of 4.4 emu g(-1) and a coercivity of 95 Oe).

Facile preparation of low cytotoxicity fluorescent carbon nanocrystals by electrooxidation of graphite.

A simple and facile method was developed to prepare fluorescent carbon nanocrystals (CNCs) with low cytotoxicity and no photobleaching, by electrooxidation of graphite in aqueous solution.