A drug-mediated organic electrochemical transistor for robustly reusable biosensors.

Reusable point-of-care biosensors offer a cost-effective solution for serial biomarker monitoring, addressing the critical demand for tumour treatments and recurrence diagnosis. However, their realization has been limited by the contradictory requirements of robust reusability and high sensing capability to multiple interactions among transducer surface, sensing probes and target analytes. Here we propose a drug-mediated organic electrochemical transistor as a robust, reusable epidermal growth factor receptor sensor with striking sensitivity and selectivity. By electrostatically adsorbing protonated gefitinib onto poly(3,4-ethylenedioxythiophene):polystyrene sulfonate and leveraging its strong binding to the epidermal growth factor receptor target, the device operates with a unique refresh-in-sensing mechanism. It not only yields an ultralow limit-of-detection concentration down to 5.74 fg ml-1 for epidermal growth factor receptor but, more importantly, also produces an unprecedented regeneration cycle exceeding 200. We further validate the potential of our devices for easy-to-use biomedical applications by creating an 8 × 12 diagnostic drug-mediated organic electrochemical transistor array with excellent uniformity to clinical blood samples.

Organic topological insulators (OTI): a dream coming true?

Experimental discovery of organic topological insulators (OTI) is a dream for both topological matters and organic materials. Despite great challenges, we anticipate that the dream will become a reality by engineered studies on materials chemistry, characterization techniques and device physics of conjugated molecules.

Reactive silica nanoparticles turn epoxy coating from hydrophilic to super-robust superhydrophobic.

Superhydrophobic organic-inorganic hybrid nanocomposite coatings have received much attention because they possess the advantages of both inorganic and organic materials. Nevertheless, it is difficult to achieve strong bonding of inorganic nanoparticles to the polymer matrix while maintaining a sufficiently rough structure to impart superhydrophobicity. In this study, we fabricated silica nanoparticles with surface reactive groups that can further react with the epoxy resin. Thus, the hydrophobic silica nanoparticles were stably anchored and stabilized in the cured resin matrix while forming nanometer-scale roughness structures. The obtained silica-decorated epoxy resin coating shows great durability and water-repellency after mechanical abrasions and has superior adhesion to the substrate.