Single-step turn-on homogeneous fluorescent immunosensor for rapid, sensitive, and selective detection of proteins

Current methods for stress marker detection in saliva

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Introduction of relevant biomarkers in stress conditions.

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Reference ranges of biomarkers in normal conditions.

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Saliva as easy-accessible specimen.

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Review of analytical methods for biomarker determination in saliva.

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Possibilities for design of point-of-care devices.

Stress and stress-related diseases are leading to drastic consequences in private and professional life. Therefore, the need for stress prevention strategies is of personal and economic interest. Especially during the recent period related to covid-19 outbreak and lock-down, an ongoing discussion of increasing stress etiology is reported. Biomarker analysis may help to assist diagnosis and classification of stress-related diseases and therefore support therapeutical decisions. Due to its non-invasive sampling, the analysis of saliva has become highly attractive compared to the detection methods in other specimen. This review article summarizes the status of research, innovative approaches, and trends. Scientific literature published since 2011 was excerpted with concentration on the detection of up to seven promising marker substances. Most often reported cortisol represents the currently best evaluated stress marker, while norepinephrine (noradrenaline) or its metabolite 3-methoxy-4-hydroxyphenylglycol is also a quite commonly considered stress marker. Other complementary stress marker candidates are testosterone, dehydroepiandrosterone (DHEA) and its sulfonated analogue DHEA-S, alpha-amylase, secretory immunoglobulin A, and chromogranin A. Several working groups are researching in the field of stress marker detection to develop reliable, fast, and affordable methods. Analytical methods reported mainly focused on immunological and electrochemical as well as chromatographic methods hyphenated to mass spectrometric detection to yield the required detection limits.

A novel dinuclear iridium(III) complex as a G-quadruplex-selective probe for the luminescent switch-on detection of transcription factor HIF-1α

A novel dinuclear Ir(III) complex 5 was discovered to be specific to G-quadruplex DNA, and was utilized in a label-free G-quadruplex-based detection platform for transcription factor activity. The principle of this assay was demonstrated by using HIF-1α as a model protein. Moreover, this HIF-1α detection assay exhibited potential use for biological sample analysis.