Electromagnetic Resonance Spectroscopy in Multifunctional Sensor Technology

This article investigates an experimental technology for the non-contact measurement of the acidity level of liquid biological media intended for application within the infrastructure of a smart pharmacist's office, intelligent pharmaceutical storage systems, and smart manufacturing environments of pharmaceutical production facilities. Particular attention is devoted to the development of an innovative measurement system based on various electromagnetic sensor configurations designed to improve the accuracy, speed, and technological efficiency of acidity monitoring while reducing dependence on conventional contact-based measurement methods.

The study demonstrates that existing standard techniques for acidity determination require mandatory preliminary calibration of measuring equipment using reference buffer solutions, which substantially increases the duration of the measurement procedure and limits the implementation of real-time automated monitoring in intelligent pharmaceutical manufacturing systems. The necessity of developing alternative engineering solutions capable of minimizing calibration-related constraints while improving the operational efficiency of measurement technologies is therefore substantiated.

Particular attention is given to a comprehensive series of experimental investigations performed using distilled water, tap water, and model samples of synthetic gastric fluid with controlled physicochemical properties. Concentrated hydrochloric acid prepared under laboratory conditions was used to modify the acidity of the test samples. Experimental measurements were carried out employing several electromagnetic sensor configurations, including a planar sensor design that demonstrated the highest levels of sensitivity, measurement accuracy, and technological potential.

The analysis of the experimental results, together with an extensive international patent survey, indicates that the application of a planar electromagnetic sensor for the non-contact determination of the acidity of liquid biological media represents a novel engineering solution that has not previously been reported for this class of measurement systems. The obtained results demonstrate the significant potential of the proposed technology for the development of intelligent autonomous devices for continuous acidity monitoring, including miniaturized capsule-based systems intended for monitoring gastric fluid acidity.

Special emphasis is placed on the comprehensive evaluation of the metrological characteristics of the proposed measurement system. The experimental program included investigations of sensor sensitivity to variations in acidity, electrical conductivity, temperature, chemical composition of the test media, and the presence of organic inclusions. In addition, the repeatability of measurement results was evaluated, the obtained data were compared with the readings of conventionally calibrated reference instruments, and the maximum permissible measurement deviations for the monitored parameters were determined.

The obtained results confirm the feasibility and technological potential of employing planar electromagnetic sensors as the foundation of a new generation of intelligent measurement systems intended for digital pharmaceutical technologies, automated quality control of biological fluids, and integration into smart pharmaceutical manufacturing infrastructures. The proposed technology provides a promising basis for the further development of highly accurate non-contact monitoring methods and advanced intelligent medical and pharmaceutical measurement systems.