A novel microwave microfluidic sensor for purity detection of Medicines’ raw materials

• Published in: International journal of electronics and communications 2024-12, Vol.187, p.155541, Article 155541
• Main Authors: Jafari, Fahimeh, Rad Malekshahi, Mazdak
• Format: Article
• Language: English
• Subjects: Complex permittivity; Microwave sensor; PDMS microfluidic holder; Resonance frequency
• ISSN: 1434-8411
• DOI: 10.1016/j.aeue.2024.155541

•A microwave microfluidic sensor with novel design can detect the purity of liquids.•Liquids with different permittivity shift the resonance frequency of the resonator.•Microwave microfluidic sensors can detect the purity of medicines’ raw materials. A novel microwave microfluidic sensor is offered for purity detection of medicine’s raw materials which is composed of two radial components and a PDMS microfluidic holder to apply the test samples. The basis of the sensing method is the shift in the resonance frequency and quality factor of the resonator in the presence of liquids with different complex permittivity. To investigate the performance of the proposed sensor, various solvents, binary mixtures of ethanol–water, and raw materials of 3 different medicines have been checked and a 980 MHz variation of resonance frequency, which provided a very high sensitivity equal to 0.53, was achieved for a complex permittivity range of 1–78.4. The proposed sensor has a small size, simple design, easy fabrication process, and very high sensitivity while it is fabricated on an FR4 substrate which decreases the total cost significantly.