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arXiv · 2511.04507

Portable, cost_effective UV_vis_NIR microspectrophotometer for absorption and fluorescence microscopy and spectroscopy

Negar Karpourazar·Keyvan Khosh Abady·Peter M. Rentzepis
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Abstract

This article describes the design and construction of a portable, compact, and cost-effective microspectrophotometer (MSP) that operates in the range of (200_800 nm). This microscope spectrophotometer records highresolution absorption and emission spectra in situ. The dual head design of this MSP enables simultaneous real time imaging and spectral recording of heterogeneous samples with high selectivity and micrometer spatial resolution. Our compact, portable MSP design reduces construction costs by more than 20 times compared to commercial benchtop alternatives, primarily due to its innovative illumination system and microscope objective design. The performance of the UV_vis_NIR MSP was confirmed by comparing the absorption and fluorescence spectra of an aqueous solution of Ru(bpy) obtained with our system to those measured by commercial spectroscopic systems. The high accuracy and reliability of our system in measuring absorbance and fluorescence were confirmed by R squared values of 0.998 and 0.990, respectively, from colorimetric and fluorometric tests. The MSP was further used to record absorption and fluorescence spectra from a variety of samples, including dyes and protein crystals, in both the solution and solid state, as well as individual living cells. This compact instrument is ideal for rapid, in situ spectroscopic measurements and is expected to find on site applications across various fields, such as environmental monitoring, biological research, forensic analysis, and materials characterization.

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Negar Karpourazar, Keyvan Khosh Abady, Peter M. Rentzepis. 2025-11-06. Portable, cost_effective UV_vis_NIR microspectrophotometer for absorption and fluorescence microscopy and spectroscopy. https://doi.org/10.1016/j.measurement.2025.118224

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