Microfluidic Sensor Based on Composite Left-Right Handed Transmission Line

Abstract

In this paper, we propose a novel metamaterial-based microfluidic sensor that permits the monitoring of properties of the fluid flowing in the microfluidic reservoir embedded between the composite left–right handed (CLRH) microstrip line and the ground plane. The sensor’s working principle is based on the phase shift measurement of the two signals, the referent one that is guided through conventional microstrip line and measurement signal guided through the CLRH line. At the operating frequency of 1.275 GHz, the CLRH line supports electromagnetic waves with group and phase velocities that are antiparallel, and therefore the phase “advance” occurs in the case of CLRH line, while phase delay arises in the right-handed (RH) frequency band. The change of the fluid’s properties that flow in the microfluidic reservoir causes the change of effective permittivity of the microstrip substrate, and subsequently the phase velocity changes, as well as the phase shift. This effect was used in the design of the microfluidic sensor for the measurement of characteristics of the fluid that flows in the microfluidic reservoir placed under the CLRH line. The complete measurement system was developed including the Wilkinson power divider that splits the signal between conventional RH and CLRH section, transmission lines with the microfluidic reservoirs, and a detection circuit for phase shift measurement. Measurement results for different fluids confirm that the proposed sensor is characterized by relatively high sensitivity and good linearity (R2 = 0.94). In this study, the practical application of the proposed sensor is demonstrated for the biomass estimation inside the microfluidic bioreactors, which are used for the cultivation of MRC-5 fibroblasts.

Cultivating Multidisciplinarity: Manufacturing and Sensing Challenges in Cultured Meat Production

“…A particularly interesting application of the microfluidics is in scale-down analysis , where compact microfluidic platforms integrated with diverse sensing technologies have been used for the analysis of different bioprocessing to resolve scale-up problems, since the microfluidic devices enable a significant reduction in time and cost of bioprocess development, and allow a high degree of process parameters control, subsequent treatment and analysis [ 103 , 104 ]. Simply put, the evaluation of different sensor prototypes is more efficient in such a controlled system as µBRs [ 105 ].…”

Engineering Metamaterials: Present and Future

“…Based on this principle, an absorber panel has been experimentally realized and validated. In Reference [14], a microfluidic sensor based on a composite left-right handed transmission line has been proposed and investigated. A change in the properties of the fluid that fills the microfluidic reservoir causes a change in the effective substrate permittivity, which subsequently changes the phase velocity in the transmission line.…”

Fabrication of ITO microelectrodes and electrode arrays using low-cost CO2 laser plotter

“…Using laser cutting for quickly transferring a pattern drawn in a computer aided design (CAD) program to a plastic film or PDMS slab for microfluidics, sometimes known as xurography, has risen in popularity as CO2 laser cutters have become more affordable and easier to use [22]. Based on this technology a microfluidic sensor which was used to evaluate the biomass of the MRC-5 fibroblast cells grown in the microfluidic bioreactor was recently presented [23]. In addition to traditional PDMS channels, CO2 lasers have also been used for patterning paper-based microfluidic systems and modifying the surface properties of the paper [24,25].…”