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Wearable sensors enable continuous and non-invasive monitoring of biomarkers, facilitating home-based healthcare and reducing the reliance on costly laboratory tests. Here, we present a wearable electrochemical sensor based on laser-induced graphene (LIG) fabricated using polyimide and transferred onto a commercial adhesive bandage for the simultaneous detection of uric acid (UA) and ascorbic acid (AA) in sweat. The electrodes displayed a carbon-rich, homogeneous morphology with a hydrophilic surface, enhancing analyte interaction. The repeatability and reproducibility studies showed satisfactory relative standard deviations (RSD) values equal to 2.7 and 8.2%, respectively. Analytical performance for AA and UA was evaluated by differential pulse voltammetry (DPV) measurements in phosphate-buffered saline (PBS). In simultaneous detection, the sensor exhibited a linear response from 20 to 200 μmol l⁻¹(R²= 0.99) for AA and UA. The limit of detection (LOD) was 6.6 μmol l⁻¹and 6 μmol l⁻¹for AA and UA, respectively. The device was further applied in artificial sweat, exhibiting minimal interference (<10%) and recoveries of 96%–100% for AA and 90%–115% for UA (n = 3). These results demonstrate the potential of this low-cost (∼US$0.5/unit) flexible sensor as a practical platform for biofluid analysis. 

Combining electrochemistry with microfluidics is attractive for a wide array of applications including multiplexing, automation, and high-throughput screening. Electrochemical instrumentation also has the advantage of being low-cost and can enable high analyte sensitivity. For many electrochemical microfluidic applications, carbon electrodes are more desirable than noble metals because they are resistant to fouling, have high activity, and large electrochemical solvent windows. At present, fabrication of electrochemical microfluidic devices bearing integrated carbon electrodes remains a challenge. Here, a new system for integrating polycaprolactone (PCL) and carbon composite electrodes into microfluidics is presented. The PCL : carbon composites have excellent electrochemical activity towards a wide range of analytes as well as high electrical conductivity (∼1000 S m −1 ). The new system utilizes a laser cutter for fast, simple fabrication of microfluidics using PCL as a bonding layer. As a proof-of-concept application, oil-in-water and water-in-oil droplets are electrochemically analysed. Small-scale electrochemical organic synthesis for TEMPO mediated alcohol oxidation is also demonstrated. 

An inexpensive, transparent, catalytic, and highly stable material is the holy grail for a dye sensitized solar cell (DSSC) cathode. Despite a near exponential increase in research effort on DSSC cathodes, materials approaching this ideal have yet to be found. Transparent cathodes allow for front and back illumination of the solar cell, enable alternative anode materials and cell designs, and are important both for fundamental research and commercialization of DSSCs. In this work, thin polymeric films of nickel tetraminophthalocyanine (NiTAPc) were tested as a catalytic cathode material in Co(Bipy)-mediated DSSCs. The thin films are highly transparent with a transmittance at 550 nm (T550) of over 95% while maintaining an R ct value below 1.3 Ω cm 2 . The NiTAPc films are inexpensive, fast and easy to generate, and stable to 2000 cyclic voltammetry cycles. Long-term film stability was not realized, and a rise in the R ct over time (days) occurred. However, poly-NiTAPc still represents one of the most transparent and catalytic materials reported to date. While historically phthalocyanines (Pc) have been studied as a dye/sensitizer, this first report of phthalocyanine use as a cathode material demonstrates they have utility on both sides of the DSSC.