This work presents a new multilayered microfluidic platform, manufactured using a rapid and cost-effective xurography technique, for the detection of drug concentrations in sweat. Textile fabrics made of cotton and polyester were used as a component of the platform, and they were positioned in the middle of the microfluidic device. In order to obtain a highly conductive textile, the fabrics were in situ coated with different amounts of polyaniline and titanium dioxide nanocomposite. This portable microfluidic platform comprises at least three layers of optically transparent and flexible PVC foils which were stacked one on top of the other. Electrical contacts were provided from the edge of the textile material when a microfluidic variable resistor was actually created. The platform was tested in plain artificial sweat and in artificial sweat with a dissolved cytostatic test drug, cyclophosphamide, of different concentrations. The proposed microfluidic device decreased in resistance when the sweat was applied. In addition, it could successfully detect different concentrations of cytostatic medication in the sweat, which could make it a very useful tool for simple, reliable, and fast diagnostics.

Accurate and consistent measurement of plantar pressure and gait analysis holds significant importance in guiding gait training for neurologically injured patients and others undergoing gait rehabilitation at home. In this paper, the fabrication of cost-effective force sensing resistors (FSRs) using rattan as a substrate and aluminum foil for sensing purposes is shown. A total of six unique combinations were generated by combining two types of rattan surfaces and three dissimilar materials (Kapton, blue cotton fabric, and white cotton fabric) for printing the carbon layer to create FSRs to print the carbon layer by an unconventional subtractive xurographic technique using a conductive layer of aluminum (foil). The sensitivity of all types of sensors was determined and compared using a compression test. All produced sensors showed the same characteristic diagram of the FSRs dependence resistance as commercial sensors. Two FSRs were selected to measure the pressure applied at the first metatarsal heads and the heel during the gait test. The test involved five subjects of different ages taking a hundred steps and wearing a custom insole created using the 3D printing fused deposition modeling (FDM) technique. The sensors successfully detected the force during the subjects’ walking and were not damaged even after the tests.

Minimally invasive recording of intracellular action potentials in electrogenic cells is in high demand. Present tools and technology include invasive patch clamp technique, 3D nanostructures often combined with electro/opto poration methods and nanodevices such as nanowire field-effect transistors. However, these approaches mostly require complex manufacturing processes or are invasive. With the aim of enabling a cost-effective, non-invasive recording platform based on devices that can be easily fabricated and processed from solution with large-area printing techniques, we propose planar Electrolyte Gated Field-Effect Transistors (EGFETs) based on solution-processed carbon based material. Remarkably, despite the planar geometry of the device, we could demonstrate the spontaneous recording of intracellular action potentials of human induced pluripotent stem cells derived cardiomyocytes. The simplicity of the device combined with the high signal to noise ratio opens up new opportunities for low-cost, reliable, and flexible biosensors and arrays for high quality parallel recording of cellular action potentials.