Demonstration of a mid-infrared cavity enhanced absorption spectrometer for breath acetone detection.

Anal Chem

Department of Chemistry, Physical and Theoretical Chemistry Laboratory, University of Oxford, South Parks Road, Oxford, OX1 3QZ, United Kingdom.

Published: January 2013

A high-resolution absorption spectrum of gaseous acetone near 8.2 μm has been taken using both Fourier transform and quantum cascade laser (QCL)-based infrared spectrometers. Absolute absorption cross sections within the 1215-1222 cm(-1) range have been determined, and the spectral window around 1216.5 cm(-1) (σ = 3.4 × 10(-19) cm(2) molecule(-1)) has been chosen for monitoring trace acetone in exhaled breath. Acetone at sub parts-per-million (ppm) levels has been measured in a breath sample with a precision of 0.17 ppm (1σ) by utilizing a cavity enhanced absorption spectrometer constructed from the QCL source and a linear, low-volume, optical cavity. The use of a water vapor trap ensured the accuracy of the results, which have been corroborated by mass spectrometric measurements.

Download full-text PDF

Source
http://dx.doi.org/10.1021/ac3031465DOI Listing

Publication Analysis

Top Keywords

cavity enhanced
8
enhanced absorption
8
absorption spectrometer
8
breath acetone
8
demonstration mid-infrared
4
mid-infrared cavity
4
absorption
4
spectrometer breath
4
acetone
4
acetone detection
4

Similar Publications

With the advancement of genetic code expansion, the field is progressing towards incorporating multiple non-canonical amino acids (ncAAs). The specificity of aminoacyl-tRNA synthetases (aaRSs) towards ncAAs is a critical factor, as engineered aaRSs frequently show polyspecificity, complicating the precise incorporation of multiple ncAAs. To address this challenge, predicting binding affinity can be beneficial.

View Article and Find Full Text PDF

Rationale: Peritoneal mucinous cystadenoma is rare in the clinic, lacks specific clinical manifestations, tumor markers, and imaging features, and is easily misdiagnosed and missed. Clinical practitioners should maintain a high level of vigilance. Here, we report a case of laparoscopic peritoneal mucinous cystadenoma stripping to improve our understanding of the disease.

View Article and Find Full Text PDF

Protein self-assembly allows for the formation of diverse supramolecular materials from relatively simple building blocks. In this study, a single-component self-assembling hydrogel is developed using the recombinant protein CsgA, and its successful application for spinal cord injury repair is demonstrated. Gelation is achieved by the physical entanglement of CsgA nanofibrils, resulting in a self-supporting hydrogel at low concentrations (≥5 mg mL).

View Article and Find Full Text PDF

Background: Several epidemiological studies and intervention trials have demonstrated that grapes and blueberries, which are rich in flavanols, can lower the risk of cardiovascular disease. However, the mechanisms of action of these compounds remain unclear due to their low bioavailability.

Objective: This study aimed to characterize the sensory properties, blood flow velocity, and oxidative stress of a polyphenol rich grape and blueberry extract (PEGB) containing approximately 16% flavanols (11% monomers and 4% dimers).

View Article and Find Full Text PDF

Anatomical and Embryological Development of the Chick Cerebrum in Different Embryonic Periods.

Vet Med Sci

January 2025

Faculty of Health Sciences, Department of Nutrition and Dietetics, Karamanoglu Mehmetbey University, Karaman, Turkey.

The objective of this study is to assess the embryological and morphometric development of the chick cerebrum during specific incubation periods. The cerebrums of 24 Babcock White Leghorn chicks, six each from the 10th, 13th, 16th and 21st days of the incubation period, were used in the study. After removing the heads of fixed embryos from the upper edge of the atlas, the brains were taken out of the cranial cavity.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!