Multi-Purpose Microwave Biosensor Based on Signal Encoding Technique and Microfluidics for Improved Sensitivity

Autor(es)

Souza, Mateus I. O. ^[1] ; Mota, Achiles Fontana Da ^[2] ; Pepino, Vinicius Marrara ^[1] ; Carmo, Joao Paulo ^[1] ; Borges, Ben-Hur Viana ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Dept Elect & Comp Engn, Sao Carlos Sch Engn, BR-13566590 Sao Paulo - Brazil

^[2] Univ Brasilia, Dept Elect Engn, BR-70910900 Brasilia, DF - Brazil

• Tipo de documento: Artigo Científico
• Fonte: IEEE SENSORS JOURNAL; v. 21, n. 4, p. 4571-4581, FEB 15 2021.
• Citações Web of Science: 0

Resumo

In this paper, a microwave biosensor with unprecedented sensitivity based on encoded pulse propagation and microfluidics is theoretically investigated and experimentally demonstrated. The structure consists of a double-spiral transmission line on FR4 substrate electromagnetically coupled to a copper coiled capillary tube above it. The working principle for improved sensitivity consists of propagating an encoded sequence of short pulses (Walsh-Hadamard spreading code with variable temporal length) in a recirculating manner so that the pulses are deformed both due to dispersive and time-delay effects. Once the recirculation is finished, the energy of the code at the sensor output is calculated, providing an indicator directly related with the analyte concentration. The experimental results demonstrate the improved sensitivity of this sensor approach for the case of glucose with 2.9 mg/ml resolution. Furthermore, we demonstrate the potential of this technology as a sensor platform by investigating other chemical compounds such as isopropyl alcohol (IPA) and acetone with a sensitivity of 20% of the volume. Finally, the outstanding performance, both in terms of accuracy and sensitivity, situates the present multi-purpose approach within the state-of-the-art of microwave (bio)chemical sensors. (AU)

• Processo FAPESP: 19/05248-7 - Microdispositivo CMOS para novas terapias de estimulação cerebral profunda
• Beneficiário: João Paulo Pereira Do Carmo
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 13/07276-1 - CEPOF - Centro de Pesquisa em Óptica e Fotônica
• Beneficiário: Vanderlei Salvador Bagnato
• Modalidade de apoio: Auxílio à Pesquisa - Centros de Pesquisa, Inovação e Difusão - CEPIDs