Biology subjects

Stepula, E.

Publications and source records attributed to Stepula, E..

3 recordsLinked to original sources

bioRxiv2025

Open Raman Microscopy (ORM): A Modular Hardware and Software Framework for Accessible Raman Imaging

Raman microscopy is a label-free, non-destructive imaging tool for spatially resolved chemical fingerprinting. Its powerful ability to reveal molecular information has driven rapid growth in applications across fields as varied as materials science, environmental analysis, and biomedical research. Despite its versatility, the accessibility of Raman microscopy is limited by expensive commercial setups and the technical barriers faced by researchers attempting to build custom systems. Here, we introduce an Open Raman Microscopy (ORM) framework based on a readily accessible modular microscopy platform. The ORM platform provides configurations for both high-throughput imaging and confocal imaging. We developed a dedicated python-based control and acquisition software, the ORM-Integrated Raman and Imaging Software (ORM-IRIS) designed to accommodate modular integration and control of components, including the laser source, spectrometer, and translational stages. Implemented across three institutions we demonstrate the ORM platform for high-throughput imaging of articular cartilage tissue, confocal three-dimensional imaging of a zebrafish embryo, and imaging of gold colloid decorated surfaces for surface enhanced Raman spectroscopy. Together, this open-source hardware and software framework enhances the accessibility of Raman microscopy across an expanding range of scientific applications.

biophysics↗

bioRxiv2023

Label-free 3-D molecular imaging of living tissues using Raman Spectral Projection Tomography

The ability to image tissues in three-dimensions (3-D) with label-free molecular contrast at mesoscale would be a valuable capability in biology and biomedicine. Here, we introduce Raman spectral projection tomography (RSPT) for volumetric molecular imaging with sub-millimeter spatial resolution. We have developed a RSPT imaging instrument capable of providing 3-D molecular contrast in transparent and semi-transparent samples. A computational pipeline for multivariate reconstruction was established to extract label-free spatial molecular information from Raman projection data. We demonstrate imaging and visualization of phantoms of various complex shapes with label-free molecular contrast. Finally, we apply RSPT as a novel tool for imaging of molecular gradients and extracellular matrix heterogeneities in fixed and live tissue-engineered constructs and explanted native tissues. RSPT imaging opens new possibilities for label-free molecular monitoring of tissues.

bioengineering↗

bioRxiv2023

Opto-lipidomics of tissues

Lipid metabolism and signalling play pivotal functions in biology and disease development. Despite this, there is currently no optical technique available that can directly visualise the lipidome in tissues. In this study, we introduce opto-lipidomics, a new approach to optical molecular tissue imaging. We expand the capability of vibrational Raman spectroscopy to identify individual lipids in complex tissue matrices through correlation with desorption electrospray ionisation (DESI) - mass spectrometry imaging in an integrated instrument. A computational pipeline of inter-modality regression analysis is established to extract lipidomic information from optical vibrational spectra. Opto-lipidomic imaging of transient cerebral ischemia-reperfusion injury in a murine model of ischemic stroke demonstrates the visualisation and identification of lipids in disease with unprecedented molecular specificity using light. Furthermore, we deploy opto-lipidomics in a handheld fiber-optic Raman probe and demonstrate real-time classification of bulk brain tissues based on specific lipid abundances. Opto-lipidomics opens a host of opportunities to study lipid biomarkers for diagnostics, prognostics, and novel therapeutic targets.

bioengineering↗