Polakova, K. | Search bioRxiv

bioRxiv2025

Surface-Enhanced Raman Spectroscopy-Assisted Lateral Flow Test for Adenine and IgG Analysis

The development of analytical methods allowing a fast and easy to perform chemical analysis of complex samples under non-laboratory conditions presents a considerable scientific challenge that requires attention. Many analytical tasks are performed using commercially available immunochemistry based lateral flow tests, where the results are detected via a direct observation of the color change of the test strip. However, these tests in many cases do not have the desired levels of selectivity and/or sensitivity or even in some cases introduce an unwanted degree of subjectivity and thus uncertainty. Here, we developed a novel lateral flow analysis test designed for easy-to-run and easily to-interpret detection implementing surface enhanced Raman scattering. The strip utilizes modular polymeric sections specifically engineered to simplify the separation of target analytes from complex biological samples. This separation relies on a series of carefully designed physicochemical interactions between the sample components and the polymeric materials embedded in the strip. A key feature of this detection method is an analytical area on the strip that incorporates plasmonic silver nanostructures with a possibility of further surface functionalization using various selectors. We evaluated this test on the selective detection of IgG through its antibody and Adenine, as representatives of proteins and low molecular compounds. This innovative test format combines modular design with advanced detection, offering significant potential for applications in biomedical research, diagnostic testing, and monitoring of immune function. HighlightsO_LIReliable and fast detection of low-molecular-weight substances and proteins. C_LIO_LICombination of modular polymer lateral flow tests and SERS analysis. C_LIO_LIDetection of complex samples, pre-separation, and pre-concentration of analytes prior to the detection. C_LI Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=99 SRC="FIGDIR/small/659022v1_ufig1.gif" ALT="Figure 1"> View larger version (23K): org.highwire.dtl.DTLVardef@e12e13org.highwire.dtl.DTLVardef@197ef2eorg.highwire.dtl.DTLVardef@1d7d07forg.highwire.dtl.DTLVardef@1b946e5_HPS_FORMAT_FIGEXP M_FIG C_FIG

immunology↗

bioRxiv2024

Divergent marine anaerobic ciliates harbor closely related Methanocorpusculum endosymbionts

Ciliates are a diverse group of protists known for their ability to establish various partnerships and thrive in a wide variety of oxygen-depleted environments. Most anaerobic ciliates harbor methanogens, one of the few known archaea living intracellularly. These methanogens increase the metabolic efficiency of host fermentation via syntrophic use of host end-product in methanogenesis. Despite the ubiquity of these symbioses in anoxic habitats, patterns of symbiont specificity and fidelity are not well known. We surveyed two unrelated, commonly found groups of anaerobic ciliates, the Plagiopylea and Metopida, isolated from anoxic marine sediments. We sequenced host 18S rRNA and symbiont 16S rRNA marker genes as well as the symbiont ITS region from our cultured ciliates to identify hosts and their associated methanogenic symbionts. We found that marine ciliates from both of these co-occurring, divergent groups harbor closely related yet distinct intracellular archaea within the Methanocorpusculum genus. The symbionts appear to be stable at the host species level, but at higher taxonomic levels, there is evidence that symbiont replacements have occurred. Gaining insight into this unique association will deepen our understanding of the complex transmission modes of marine microbial symbionts, and the mutualistic microbial interactions occurring across domains of life.

microbiology↗