Optical detection of microplastics in pharmaceutical samples using Visible-Region spectroscopy

Document Type : Research

Authors
Setayesh Yarahmadi
Salman Mohajer
Kharazmi
10.22034/jmrph.2026.122917.0
Abstract
In this study, healthy and artificially contaminated pharmaceutical samples prepared under laboratory conditions were investigated using two optical configurations, namely reflective and transmissive arrangements, to distinguish between healthy and contaminated samples after illumination with a light source. In the optical configurations, parameters such as peak size, peak width, peak position, and spectral images were obtained following illumination of the samples. In the transmission configuration, after fitting an appropriate curve and analyzing the peak width, peak size, and peak position, approximately 11 pharmaceutical samples, including ophthalmic and topical ointments with two different expiration dates, were evaluated. The results showed that, on average, the peak width of the healthy samples was greater than that of the contaminated samples. Regarding the peak positions, the position of the first peak remained unchanged between the healthy and contaminated samples, whereas the position of the second peak shifted toward lower values in the contaminated samples. The different expiration dates of the ophthalmic and topical ointments did not have a significant effect on the results. These findings indicate that the proposed approach may serve as a novel visible-region spectroscopic method for detecting microplastics in pharmaceutical samples.
Keywords
Spectroscopy
Microplastics
Pharmaceutical samples
Spectral width
Optical configuration
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Journal Of Modern Research Physics
Volume 11, Issue 1 - Serial Number 20
September 2026
Pages 67-75