SNaP-C: Validation of a novel, selective silver nanoparticle antioxidant capacity assay for Vitamin C content in beverages.

A validated silver nanoparticle assay (SNaP-C) for quantitation of Vitamin C, as ascorbic acid (AA) and total AA (TAA), was applied to 31 beverages. SNaP-C assay results (LOD of 2.2 mg/L AA) were compared to AA and TAA determined by high-performance liquid chromatography with UV/Vis (LOD = 0.

Micro-extraction method for the analysis of flame retardants in dust collected from air filters from HVAC systems.

Dust is a sink for many semi-volatile compounds including flame retardants of the organophosphate ester (OPE) and brominated flame-retardant (BFR) classes. Given the large amount of time that we spend indoors, our exposure to these compounds via dust is of significant interest. Here, we present a novel microextraction approach to determine quantitative levels of selected OPEs and BFRs sampled from residential air filters from HVAC systems using a small volume of solvent.

Exploring the residential exposome: Determination of hazardous flame retardants in air filter dust from HVAC systems.

Dust is a sink for flame retardants, which are added to a myriad of consumer products in residential spaces. Organophosphate esters (OPEs) and brominated flame retardants (BFRs) are two classes of flame retardants that are frequently used in consumer products and consequently found in dust. In this present work, a novel solvent-limited microextraction technique, which we detailed in a companion study, was applied for the determination of four OPEs and two BFRs with limits of quantitation at the ng/g level by gas chromatography-mass spectrometry and liquid chromatography-mass spectrometry from n = 47 air filter dust samples collected from forced air HVAC systems.

Headspace versus direct injection for the quantitation of methanol, ethyl acetate, and fusel oils in distilled spirits by gas chromatography - Flame ionization detection.

Distilled spirits can be very complex in their sensory or organoleptic compounds. Of significant interest is determination of the concentration of methanol, ethyl acetate, and fusel oils, which include n-propanol, isobutanol, n-butanol, active amyl (2-methyl-1-butanol) and isoamyl (3-methyl-1-butanol) alcohols. Here, we describe a validated method for the analysis of these analytes using a headspace (HS) sampling unit coupled with a gas chromatograph fitted with a flame ionization detector (GC/FID) for profiling these analytes in distilled spirits ( = 26) obtained from local retailers.

Dataset of surveyed PFAS in water, sediment, and soil of Fountain Creek Watershed, Colorado, USA.

Per- and polyfluoroalkyl substances (PFAS) are widespread and highly persistent organic chemicals with adverse health effects. The US Environmental Protection Agency has issued health advisory limits of 70 ng/L for aqueous concentrations of PFOA + PFOS. In the Colorado Springs, Colorado (USA), metro area, the Widefield Aquifer (groundwater) and Fountain Creek Watershed (surface water) have been contaminated by PFAS from aqueous film-forming foams.

Analysis of sugars and amino acids in aphid honeydew by hydrophilic interaction liquid chromatography - Mass spectrometry.

Past analyses of sugar and amino acid composition of aphid honeydews have been completed using diverse instrumentation. Here we report the use of hydrophilic interaction liquid chromatography (HILIC) coupled with a triple quadrupole mass spectrometric (MS/MS) detector for the analysis of seven saccharides (xylose, fructose, glucose, sucrose, trehalose, melezitose and raffinose) and five amino acids (glutamic acid, glutamine, aspartic acid, serine, and asparagine). Limits of quantitation ranged from 0.

Development of a low-density-solvent dispersive liquid-liquid microextraction with gas chromatography and mass spectrometry method for the quantitation of tetrabromobisphenol-A from dust.

The development of an alternative dispersive liquid-liquid microextraction protocol utilizing a low-density extraction solvent, toluene, is described here for the extraction of the brominated flame retardant, tetrabromobisphenol-A, from dust prior to selected ion monitoring analysis by gas chromatography with mass spectrometry. Method parameters of dispersive solvent type and extraction solvent type were optimized. Excellent recovery (88.

Measles outbreak associated with an international youth sporting event in the United States, 2007.

Background: Despite elimination of endemic measles in the United States (US), outbreaks associated with imported measles continue to occur. In 2007, the initiation of a multistate measles outbreak was associated with an imported case occurring in a participant at an international youth sporting event held in Pennsylvania.

Methods: Case finding and contact tracing were conducted.

Genotyping of measles virus in clinical specimens on the basis of oligonucleotide microarray hybridization patterns.

An oligonucleotide microarray hybridization method for identification of most known measles virus (MV) genotypes was developed. Like the conventional genotyping method, the microarray relied on detecting sequence differences in the 450-nucleotide region coding for the COOH-terminal 150 amino acids of the nucleoprotein (N). This region was amplified using PCR primers binding to all known MV genotypes.

Subacute sclerosing panencephalitis: more cases of this fatal disease are prevented by measles immunization than was previously recognized.

Background: The most severe sequela of measles virus infection is subacute sclerosing panencephalitis (SSPE), a fatal disease of the central nervous system that generally develops 7-10 years after infection. From 1989 through 1991, a resurgence of measles occurred in the United States, with 55,622 cases of measles reported. The purpose of the present study was to identify cases of SSPE that were associated with the resurgence of measles and to calculate the risk of developing SSPE.

Real-time reverse transcription-polymerase chain reaction assay for SARS-associated coronavirus.

A real-time reverse transcription-polymerase chain reaction (RT-PCR) assay was developed to rapidly detect the severe acute respiratory syndrome-associated coronavirus (SARS-CoV). The assay, based on multiple primer and probe sets located in different regions of the SARS-CoV genome, could discriminate SARS-CoV from other human and animal coronaviruses with a potential detection limit of <10 genomic copies per reaction. The real-time RT-PCR assay was more sensitive than a conventional RT-PCR assay or culture isolation and proved suitable to detect SARS-CoV in clinical specimens.