Agilent Technologies

About: Agilent Technologies is a company organization based out in Santa Clara, California, United States. It is known for research contribution in the topics: Signal & Mass spectrometry. The organization has 7398 authors who have published 11518 publications receiving 262410 citations. The organization is also known as: Agilent Technologies, Inc..

Preventive doping control analysis: liquid and gas chromatography time-of-flight mass spectrometry for detection of designer steroids.

Abstract: A new combined doping control screening method for the analysis of anabolic steroids in human urine using liquid chromatography/electrospray ionization orthogonal acceleration time-of-flight mass spectrometry (LCoaTOFMS) and gas chromatography/electron ionization orthogonal acceleration time-of-flight mass spectrometry (GCoaTOFMS) has been developed in order to acquire accurate full scan MS data to be used to detect designer steroids. The developed method allowed the detection of representative prohibited substances, in addition to steroids, at concentrations of 10 ng/mL for anabolic agents and metabolites, 30 ng/mL for corticosteroids, 500 ng/mL for stimulants and fl-blockers, 250ng/mL for diuretics, and 200ng/mL for narcotics. Sample preparation was based on liquid-liquid extraction of hydrolyzed human urine, and the final extract was analyzed as trimethylsilylated derivatives in GCoaTOFMS and underivatized in LCoaTOFMS in positive ion mode. The sensitivity, mass accuracy, advantages and limitations of the developed method are presented. Copyright (C) 2007 John Wiley & Sons, Ltd.

Quantitative tissue proteomics of esophageal squamous cell carcinoma for novel biomarker discovery

Abstract: Esophageal squamous cell carcinoma (ESCC) is among the top ten most frequent malignancies worldwide. In this study, our objective was to identify potential biomarkers for ESCC through a quantitative proteomic approach using the isobaric tags for relative and absolute quantitation (iTRAQ) approach. We compared the protein expression profiles of ESCC tumor tissues with the corresponding adjacent normal tissue from ten patients. LC-MS/MS analysis of strong cation exchange chromatography fractions was carried out on an Accurate Mass QTOF mass spectrometer, which led to the identification of 687 proteins. In all, 257 proteins were identified as differentially expressed in ESCC as compared to normal. We found several previously known protein biomarkers to be upregulated in ESCC including thrombospondin 1 (THBS1), periostin 1 (POSTN) and heat shock 70 kDa protein 9 (HSPA9) confirming the validity of our approach. In addition, several novel proteins that had not been reported previously were identified in our scr...

Recent applications in capillary electrochromatography

Abstract: The most recent and important applications in capillary electrochromatography (CEC) are summarized, covering literature published since May 2001. A selection of new developments in stationary phases for CEC is highlighted, and enantiomeric separations and chiral stationary phases are discussed. Also, CEC applications of biological molecules, pharmaceuticals, and applications in the field of industrial and environmental analysis are summarized. For this review three modes of CEC were taken into account, i.e., packed-column CEC, CEC using monolith technology, and open-tubular CEC.

Apparatus, systems and method for locating nucleic acids bound to surfaces

Abstract: An apparatus, systems and method for locating nucleic acids in an array on a substrate have self-locating nucleic acid features. The nucleic acid features produce nucleotide-dependent location signals or optically detectable contrast between nucleotide-bound regions and non-nucleotide-bound regions of the substrate when scanned by an optical scanner. When used as analytical tools for monitoring gene expression and mutations in gene sequences, the nucleotide features are hybridized with nucleic acids of known or unknown sequences. The apparatus, systems and method locate both weakly and strongly hybridized nucleotide features on the substrate for identification of target nucleic acid sequences. The nucleotide feature signals or contrast are independent of the optical signals conventionally produced by the hybridized nucleotides. Therefore, the apparatus, systems and method locate all of the nucleotide features, hybridized or not, independently of the extent of hybridization. The present invention advantageously self-locates both bright and dim hybridized features on an array substrate and is therefore, independent of the random and systematic errors associated with the manufacturing equipment and processes. Moreover, the present invention provides a powerful quality control tool to the in situ synthesis process. The present invention provides information about what part or percentage of each feature contains full-length probes. The present optical scanning system detects optical signals from the nucleotide features independently of the signals from the hybridized nucleotides using essentially conventional scanning technology. The independently detected signals are processed such that all features are located and the hybridized features are accurately detected and analyzed.

Mounting film bulk acoustic resonators in microwave packages using flip chip bonding technology

Abstract: A device includes a die that contains a filter circuit. The filter is implemented using film bulk acoustic resonators. A package contains the die. The package includes a base portion. Signal paths are incorporated in the base portion. Solder joints attach the die to the base portion. The solder joints electrically connect pads on the die to the signal paths in the base portion. The solder joints do not include, and are used instead of, wire bonds.