Here we report a rapid, low cost, and disposable dipstick-type DNA biosensor that enables multiplex detection in a single assay. The fluorescent probes labeled with different fluorophores were introduced into the lateral flow nucleic acid testing system. In combination with multiple immobilized probes arranged in an array formant on the membrane, a dual-color fluorescent lateral flow DNA biosensor was developed using a portable fluorescence reader. Up to 13 human papillomavirus types could be detected simultaneously by a single-step operation in less than 30 min after linear-after-the-exponential (LATE)-PCR. The sensitivity was determined to be 10-10(2) copies plasmid DNA/μL. The specificity study showed no cross-reactivity among the 31 different common HPV types. In the clinical validation, 95.3% overall agreement showed very good potential for this method in the clinical application when compared to a commercial kit.

As chemical sensors are in great demand for portable and wearable analytical applications, it is highly desirable to develop an all-solid-state ion-selective electrode (ISE) and reference electrode (RE) platform with simplicity and stability. Here we propose a wearable sensor platform with a new type of all-solid-state ISE based on a gold nanodendrite (AuND) array electrode as the solid contact and a poly(vinyl acetate)/inorganic salt (PVA/KCl) membrane-coated all-solid-state RE. A simple and controllable method was developed to fabricate the AuNDs on a microwell array patterned chip by one-step electrodeposition without additional processing. For the first time, the AuND electrodes with different real surface area and double layer capacitance were developed as solid contact of the Na-ISE to investigate the relationship between performance of the ISE and surface area. As-prepared AuND-ISE with larger surface area (∼7.23 cm) exhibited enhanced potential stability compared to those with smaller surface area (∼1.85 cm) and to bare Au ISE. Important as the ISE, the PVA/KCl membrane-coated Ag/AgCl RE exhibited highly stable potential even after 3 months' storage. Finally, a wearable sweatband sensor platform was developed for efficient sweat collection and real-time analysis of sweat sodium during indoor exercise. This all-solid-state ISE and RE integrated sensor platform provided a very simple and reliable way to construct diverse portable and wearable devices for healthcare, sports, clinical diagnosis, and environmental analysis applications.

The SELEX method and oligonucleotide combinatorial chemistry discovery process yields highaffinity͞high-specificity ligands for virtually any molecular target. Typically, the enormous starting libraries used in the SELEX process contain 10 14 -10 15 sequences. We now ask if the smaller sequences, complexity of extant organisms, and evolutionary history provide useful interactions between oligonucleotides and at least some unexpected targets. That is, do organisms contain a robust "linkage map" between their oligonucleotides and proteins and͞or small molecules that enriches life?We have accepted the challenge of writing an inaugural article, hoping to stimulate and provoke other scientists to wonder with us about a chance to discover surprising molecular interactions in biology between nucleic acids and other intracellular components. We will chart the conceptual triangle surrounding in vitro evolution [the SELEX (for systematic evolution of ligands by exponential enrichment) methodology]: insights into the prebiotic earth, applied medical research, and novel regulatory elements and circuits in cells (identified through the genomic SELEX process). We came to this set of ideas through the study of bacteriophage T4 development, with a focus on translational regulation. It was that work and the extraordinary environment for RNA studies that exists at the University of Colorado in Boulder that led us to our present interests. Translational Regulation in Bacteriophage T4-Infected Escherichia coliAmong the first experiments on coupled transcription and translation in vitro were those done in Lipmann's laboratory by one of us (1). For the first time, the synthesis of active, full-length enzymes from a DNA template was achieved. The templates used for most of those experiments were from T-even bacteriophage, which ultimately led to our interest in T4 translation and its regulation.What a time to study a simple developing system-Peter Geiduschek's and Dick Epstein's laboratories (40, 41) had made clear the phage transcriptional pattern, while the invention of high-resolution SDS gels by Uli Laemmli (42) made it possible to detect a corresponding translational pattern. We thought that the development of this organism could be understood, given the power of T4 genetics (2) and the availability of mutations in most of the essential genes.The early work we did at the University of Colorado was so simple. We received T4 mutant strains from people (who for the most part still shared things) and ran gels to see what happened to phage gene expression after infections of nonpermissive E. coli with those T4

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