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Microfluidic Paper‐based Analytical Devices (µPADs) have emerged as a new class of microfluidic systems, offering numerous advantages over traditional microfluidic chips. These advantages include simplicity, cost‐effectiveness, stability, storability, disposability, and portability. As a result, various designs for different types of assays are developed and investigated. In recent years, µPADs are combined with conventional detection methods to enable rapid on‐site detection, providing results comparable to expensive and sophisticated large‐scale testing methods that require more time and skilled personnel. The application of µPAD techniques is extensive in environmental quality control/analysis, clinical diagnosis, and food safety testing, paving the way for on‐site real‐time diagnosis as a promising future development. This review focuses on the recent research advancements in the design, fabrication, material selection, and detection methods of µPADs. It provides a comprehensive understanding of their principles of operation, applications, and future development prospects. [ABSTRACT FROM AUTHOR]

Employing responsive nanoplatforms as carriers for photosensitizers represents an effective strategy to overcome the challenges associated with photodynamic therapy (PDT), including poor solubility, low bioavailability, and high systemic toxicity. Drawing inspiration from the morphology transitions in biological systems, a general approach to enhance PDT that utilizes enzyme‐responsive nanoplatforms is developed. The transformation of phosphopeptide/photosensitizer co‐assembled nanoparticles is first demonstrated into nanofibers when exposed to cytoplasmic enzyme alkaline phosphatase. This transition is primarily driven by alkaline phosphatase‐induced changes of the nanoparticles in the hydrophilic and hydrophobic balance, and intermolecular electrostatic interactions within the nanoparticles. The resulting nanofibers exhibit improved ability of generating reactive oxygen species (ROS), intracellular accumulation, and retention in cancer cells. Furthermore, the enzyme‐responsive nanoplatform is expanded to selectively target mitochondria by mitochondria‐specific enzyme sirtuin 5 (SIRT5). Under the catalysis of SIRT5, the succinylated peptide/photosensitizer co‐assembled nanoparticles can be transformed into nanofibers specifically within the mitochondria. The resulting nanofibers exhibit excellent capability of modulating mitochondrial activity, enhanced ROS formation, and significant anticancer efficacy via PDT. Consequently, the enzyme‐instructed in situ fibrillar transformation of peptide/photosensitizers co‐assembled nanoparticles provides an efficient pathway to address the challenges associated with photosensitizers. It is envisaged that this approach will further expand the toolbox for enzyme‐responsive biomaterials for cancer therapy. [ABSTRACT FROM AUTHOR]

The development of conductive coatings has significant implications for microelectronics and electrochemistry. However, conductive coatings may exhibit different electrochemical properties when prepared on different substrate materials. This research explores the comparative performance of graphene, graphene oxide (GO), and silver nanoparticle (Ag NP) composites as conductive coatings on diverse substrate materials, including polydimethylsiloxane (PDMS), polymethyl methacrylate (PMMA), and glass. The study employed various preparation methods, such as mixing conductive materials with substrate materials and preparing copolymer composite materials. The conductive coating approach was found to be the most straightforward and convenient, with broader development prospects and fewer restrictive conditions. The results indicate that the distinct surface characteristics of the substrate materials influence the conductive properties of coating materials. Consequently, results show that graphene exhibits the highest conductivity on all three substrates, while GO is more conductive than Ag NPs on PMMA and PDMS but less conductive than Ag NPs on glass. That offers valuable insights into the selection of substrate materials and coating materials for the preparation of conductive materials. [ABSTRACT FROM AUTHOR]