In-orbit operation of an atomic clock based on laser-cooled Rb atoms.

Atomic clocks based on laser-cooled atoms are widely used as primary frequency standards. Deploying such cold atom clocks (CACs) in space is foreseen to have many applications. Here we present tests of a CAC operating in space.

Highly sensitive enumeration of circulating tumor cells in lung cancer patients using a size-based filtration microfluidic chip.

Circulating tumor cells (CTCs) in the peripheral blood could serve as a surrogate marker for the diagnosis of cancer metastasis and for therapeutic evaluation. However, the separation and characterization of CTCs is technically challenging owing to the extremely low number of CTCs present. Here we developed a size-based and high-throughput microfluidic chip, which exploits filtration microchannels to isolate the relatively larger CTCs from the rest of the blood constituents.

Enzymic colorimetry-based DNA chip: a rapid and accurate assay for detecting mutations for clarithromycin resistance in the 23S rRNA gene of Helicobacter pylori.

Macrolide drugs, such as clarithromycin (CAM), are a key component of many combination therapies used to eradicate Helicobacter pylori. However, resistance to CAM is increasing in H. pylori and is becoming a serious problem in H.

Nano-ELISA for highly sensitive protein detection.

Highly sensitive protein detection method based on nanoparticles and enzyme-linked immunosorbent assays (ELISAs), named Nano-ELISA, was introduced. In this method, the micro-magnetic beads were modified with monoclonal antibody of the target protein p53. Gold nanoparticles (AuNPs) were modified with another monoclonal detector antibody and Horseradish peroxidase (HRP, for signal amplification).

[The detection of plasmid pCAMBIA1301 in transgenic rice by arrayed primer extension].

Biochip technology which had emerged from the fusion of biotechnology and micro/nanofabrication technology at the end of 1980s has been widely used in life science, medicine, clinical diagnosis, drug development, agriculture, environmental protection and strategies. DNA microarray (also call gene chip, DNA chip), one kind of biochips, is small chip containing many oligonucleotide probes. It can hybridize with labelled sample, making it possible to detect large numbers of oligonucleotides at one time.

[Detection for single nucleotide polymorphisms].

As the third generation of genetic markers SNPs (single nucleotide polymorphisms) has been used extensively in gene mapping,disease-correlativity analysis ,population genetics and drug research. Here methods for detection are reviewed. Most SNP genotyping are a combination of method for interrogating SNPs and analysis technique.

[The use of gene chip in detecting Mycobacterium tuberculosis resistant to rifampin and isoniazid].

Objective: To study the application of gene chip in detecting Mycobacterium tuberculosis resistant to rifampin (RFP) and isoniazid (INH).

Methods: Probes were designed and the gene chip was fabricated according to the 30 single nucleotide polymorphisms of 11 mutations on 4 genes associated with RFP and INH resistance. The mutations in Mycobacterium tuberculosis were detected by gene chip to analyze the resistance to INH and RFP.

[Molecular genetic mechanism of sodium arsenite on growth and development].

Objective: To study the effects of sodium arsenite on gene expression related to growth and development and explored the molecular mechanism of arsenic effects using gene chips.

Methods: Normal human hepatic cells were dripped on chips and then hybrided with the first strand of cDNA from hepatic cell exposed to different concentration of sodium arsenite. Gene sequence of clone differently expressed was determined and then defined which gene it was and finally those genes which associated with growth and development were identified.

[Establishment of a method with micro-channel electrophoresis for detecting the mutations of isoniazid-resistant genes in Mycobacterium tuberculosis].

Objective: To establish a method for the detection of isoniazid resistance-associated mutations in katG gene and inhA gene in Mycobacterium tuberculosis with single-stranded conformation polymorphism (SSCP) analysis by the micro-channel electrophoresis chip system.

Methods: The polymer solutions of acrylamide and its derivatives were used for sieving matrices with small amount of acridine orange as the fluorescent tag. A novel pair of primers was designed to link an extra segment that could be base paired with the mutation region to the PCR products of wild type inhA gene, which made the single strands of wild type inhA fragments present a unique conformation.