This work describes a novel sequential injection chromatography (SIC) method combined with linear gradient elution for the separation and determination of three main methylxanthines (theobromine, theophylline and caffeine) using a short C18 monolithic column. The method utilizes a hybrid manifold which exploits zone fluidics for solution manipulation and programmable fluidics for the implementation of a two-solvent linear gradient elution protocol. This approach offers a high degree of automation and enables faster separation of the three target methylxanthines with respect to isocratic elution as well as better chromatographic efficiency. The limits of detection of the three methylxanthines ranged from 0.18 to 0.45 μmol L, the instrumental repeatability (at the 10 μmol L level of the target compounds, n = 6) was ≤2% and the separation time was 3.3 min. The SIC method was validated and applied to the analysis of coffee, chocolate and tea samples.
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http://dx.doi.org/10.1016/j.talanta.2019.04.046 | DOI Listing |
PLoS One
January 2025
Division of Cardiology, Department of Internal Medicine, Kaohsiung Medical University Gangshan Hospital, Kaohsiung, Taiwan.
Background/purpose: Dyslipidemia, a hallmark of metabolic syndrome (MetS), contributes to atherosclerotic and cardiometabolic disorders. Due to days-long analysis, current clinical procedures for cardiotoxic blood lipid monitoring are unmet. This study used AI-assisted attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy to identify MetS and precisely quantify multiple blood lipid levels with a blood sample of 0.
View Article and Find Full Text PDFPLoS One
January 2025
School of Architecture and Urban Planning, Lanzhou Jiaotong University, Gansu, Lanzhou, China.
The built environment is an important determinant of travel demand and mode choice. Studying the relationship between the built environment and transportation usage can support and assist traffic policy interventions. Previous studies often assumed that this relationship is linear; however, the impact of the built environment on non-motorized travel efficiency may be more complex than the typically modeled linear relationships.
View Article and Find Full Text PDFEur J Prev Cardiol
January 2025
Department of Epidemiology, School of Public Health, Harbin Medical University, 157 Baojian Road, Harbin 150081, China.
Aims: Dietary inflammatory potential and genetic factors are reported as being linked to coronary heart disease (CHD). We aimed to investigate their joint association with CHD incidence.
Methods And Results: We included 51 889 British participants from the UK Biobank who completed the 24-h dietary assessment at baseline.
J Racial Ethn Health Disparities
January 2025
Department of Biomedical Informatics, College of Medicine, University of Arkansas for Medical Sciences, Little Rock, AR, USA.
Context: To evaluate algorithmic fairness in low birthweight predictive models.
Study Design: This study analyzed insurance claims (n = 9,990,990; 2013-2021) linked with birth certificates (n = 173,035; 2014-2021) from the Arkansas All Payers Claims Database (APCD).
Methods: Low birthweight (< 2500 g) predictive models included four approaches (logistic, elastic net, linear discriminate analysis, and gradient boosting machines [GMB]) with and without racial/ethnic information.
Comput Biol Med
January 2025
Department of Mathematics and Statistics, The University of Lahore, Lahore Campus, Pakistan. Electronic address:
Glaucoma is an irreversible, progressive, degenerative eye disorder arising because of increased intraocular pressure, resulting in eventual vision loss if untreated. The QSPR relates, mathematically, by employing various algorithms, a specified property of a molecule that arises either from physical, chemical, or biological phenomena using various aspects of its structure. Here in, a similar application based on topological indices and inferences derived from the structure for the calculation of different drug properties like molar refractivity, refractive index, enthalpy, boiling points, molecular weight, and polarizability is presented.
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