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High per- and polyfluorinated alkyl substance (PFAS) concentrations have been detected in agricultural soils in Southwest Germany. Discharges of PFAS-contaminated paper sludge and compost are suspected to be the cause of the contamination. Perfluorinated carboxylic acids (PFCAs) have been detected also in groundwater, drinking water, and plants in this area. Recently, previously unknown compounds have been identified by high-resolution mass spectrometry (HRMS). Major contaminants were polyfluorinated dialkylated phosphate esters (diPAPs) and N-ethyl perfluorooctane sulfonamide ethanol–based phosphate diester (diSAmPAP). In this study, HRMS screening for PFAS was applied to 14 soil samples from the contaminated area and 14 impregnated paper samples which were from a similar period than the contamination. The paper samples were characterized by diPAPs (from 4:2/6:2 to 12:2/12:2), fluorotelomer mercapto alkyl phosphates (FTMAPs; 6:2/6:2 to 10:2/10:2), and diSAmPAP. In soil samples, diPAPs and their transformation products (TPs) were the major contaminants, but also FTMAPs, diSAmPAP, and their TPs occurred. The distribution patterns of the carbon chain lengths of the precursor PFAS in soil samples were shown to resemble those in paper samples. This supports the hypothesis that paper sludge is a major source of contamination. The presence of major degradation products like PFCAs, FTSAs, or PFOS and their distribution of carbon chain lengths indicate the activity of biotic or abiotic degradation processes and selective leaching processes from the upper soil horizons. [ABSTRACT FROM AUTHOR]

Urinary tract infections (UTIs) make up a significant proportion of the global burden of disease in vulnerable groups and tend to substantially impair the quality of life of those affected, making timely detection of UTIs a priority for public health. However, economic and societal barriers drastically reduce accessibility of traditional lab-based testing methods for critical patient groups in low-resource areas, negatively affecting their overall healthcare outcomes. As a result, cellulose-based materials such as paper and thread have garnered significant interest among researchers as substrates for so-called frugal analytical devices which leverage the material's portability and adaptability for facile and reproducible diagnoses of UTIs. Although the field may be only in its infancy, strategies aimed at commercial penetration can appreciably increase access to more healthcare options for at-risk people. In this review, we catalogue recent advances in devices that use cellulose-based materials as the primary housing or medium for UTI detection and chart out trends in the field. We also explore different modalities employed for detection, with particular emphasis on their ability to be ported onto discreet casings such as sanitary products. [ABSTRACT FROM AUTHOR]

A quantitative non-destructive express method of determining fillers —kaolin and chalk— in paper was created using attenuated total reflectance Fourier transform infrared (ATR-FT-IR) spectroscopy in the mid-IR and far-IR region (3800–245 cm−1) combined with partial least squares (PLS) data analysis. Altogether, 30 two-component (cellulose pulp + kaolin and cellulose pulp + chalk) reference paper samples with known different filler concentrations and one reference paper sample without any fillers were prepared for calibration and validation. The reference values of filler concentrations in the prepared papers were determined by gravimetric analysis via dry ashing (for establishing accurate concentrations of fillers in paper) and ATR-FT-IR microspectroscopy (for evaluating homogeneity of the papers). Two-component (cellulose pulp + kaolin or cellulose pulp + chalk) PLS models were created with papers of different cellulose types and containing different amounts of fillers. The best model had root mean square errors of prediction (RMSEP) for determining the kaolin or chalk content in the two-component papers of 2.0 and 2.1 g/100 g, respectively. The performance indices were 90.4% and 92.9%, respectively. As a demonstration of practical applicability of the method, different papers from books, journals, etc. were analysed. It was concluded that the developed quantitative method is suitable for non-destructive express analysis of kaolin or chalk in paper. [ABSTRACT FROM AUTHOR]

As an analytical support, paper, being low cost, highly abundant, of high porosity, disposable or biodegradable, and easy to use, store, transport, and print, has excellent chemical compatibility with many applications. Since the first microfluidic paper-based analytical device (μ-PAD or lab-on-paper) was proposed, the paper-based assay has never attracted as much attention as it does now. There has recently been rapidly increasing interest in using sensitive luminescence methods, for example chemiluminescence (CL) and electrogenerated chemiluminescence (ECL), as the detection strategy for lab-on-paper devices. Because of their intrinsic characteristics, CL and ECL provide outstanding performance while retaining the simplicity, low cost, multifunctionality, versatility, flexibility, and disposability of μ-PADs. The objective of this review is to cover the development of lab-on-paper-based devices using CL and ECL detection, including fabrication of paper devices, construction of sensing interfaces, signal amplification strategies, external instruments used, and applications. We believe that lab-on-paper devices with CL and ECL detection methods will meet the diverse requirements of point-of-care diagnosis. [ABSTRACT FROM AUTHOR]