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With the explosion of digital world, the dramatically increasing data volume is expected to reach 175 ZB (1 ZB = 1012 GB) in 2025. Storing such huge global data would consume tons of resources. Fortunately, it has been found that the deoxyribonucleic acid (DNA) molecule is the most compact and durable information storage medium in the world so far. Its high coding density and long-term preservation properties make itself one of the best data storage carriers for the future. High-throughput DNA synthesis is a key technology for "DNA data storage", which encodes binary data stream (0/1) into quaternary long DNA sequences consisting of four bases (A/G/C/T). In this review, the workflow of DNA data storage and the basic methods of artificial DNA synthesis technology are outlined first. Then, the technical characteristics of different synthesis methods and the state-of-the-art of representative commercial companies, with a primary focus on silicon chip microarray-based synthesis and novel enzymatic DNA synthesis are presented. Finally, the recent status of DNA storage and new opportunities for future development in the field of high-throughput, large-scale DNA synthesis technology are summarized. [ABSTRACT FROM AUTHOR]

Early screening and diagnosis are the most effective ways to prevent the occurrence and progression of cancers, thus many biosensing strategies have been developed to achieve economic, rapid, and effective detection of various cancer biomarkers. Recently, functional peptides have been gaining increasing attention in cancer-related biosensing due to their advantageous features of a simple structure, ease of synthesis and modification, high stability, and good biorecognition, self-assembly and antifouling capabilities. Functional peptides can not only act as recognition ligands or enzyme substrates for the selective identification of different cancer biomarkers but also function as interfacial materials or self-assembly units to improve the biosensing performances. In this review, we summarize the recent advances in functional peptide-based biosensing of cancer biomarkers according to the used techniques and the roles of peptides. Particular attention is focused on the use of electrochemical and optical techniques, both of which are the most commonly used techniques in the field of biosensing. The challenges and promising prospects of functional peptide-based biosensors in clinical diagnosis are also discussed. [ABSTRACT FROM AUTHOR]

Enzyme clustering is widely used in many organisms to increase the catalytic efficiency of cascade reactions. Inspired by nature, organizing enzymes within a cascade reaction also draws much attention in both basic research and industrial processes. An important step for organizing enzymes precisely in vitro is enzyme modification. However, modifying enzymes without sacrificing their activity remains challenging until now. For example, labeling enzymes with DNA, one of the well-established enzyme modification methods, has been shown to significantly reduce the enzymatic activity. Herein we report an enzyme conjugation method that can rescue the reduction of enzymatic activity caused by DNA labeling. We demonstrate that immobilizing DNA-modified enzymes on the vertex of TDNs (tetrahedral DNA nanostructures) enhances the enzymatic activity compared with their unmodified counterparts. Using this strategy, we have further developed an ultra-sensitive and high-throughput electrochemical biosensor for sarcosine detection, which holds great promise for prostate cancer screening. [ABSTRACT FROM AUTHOR]

A DNA origami nanocaliper is employed as a shape-resolved nanomechanical device, with pH-responsive triplex DNA integrated into the two arms. The shape transition of the nanocaliper results in a subtle difference depending on the local pH that is visible via TEM imaging, demonstrating the potential of these nanocalipers to act as a universal platform for pH sensing at the nanoscale. [ABSTRACT FROM AUTHOR]

Advances in bioimaging technologies have led to unprecedented findings of novel biological processes at the nanoscale. However, there remains an ever-lasting demand for the improvement of spatiotemporal resolution, multiplexity, and smart responsiveness of bioimaging in living systems. In recent decades, self-assembled DNA nanostructures with highly programmable shape, nanometer addressability, and structural responsiveness have shown great promise in developing nanoscale probes and labels for high-performance bioimaging. Here, we briefly review the recent progress in structural DNA nanotechnology and the development of DNA frameworks, and summarize the bioimaging strategies empowered by DNA nanotechnology. We highlight the advantages of DNA nanostructures in overcoming the bottlenecks in bioimaging and discuss the challenges and opportunities in this field. [ABSTRACT FROM AUTHOR]

The response sensitivity of a molecular sensor is determined by the folding cooperativity of its responsive module. Using an H+-responsive dimeric DNA i-motif as a model, we demonstrate the enhancement of its folding cooperativity through preorganization by a DNA framework, and with it we fabricate robust intracellular pH sensors with high response sensitivity. [ABSTRACT FROM AUTHOR]

Fast, portable and sensitive analysis of E. coli is becoming an important challenge in many critical fields (e.g., food safety, environmental monitoring and clinical diagnosis). Thus, electrochemical biosensing of PCR amplicons from the bacterial genome has attracted reasonable research attention. In this work, we utilized a 3D DNA tetrahedral probe to establish a “sandwich-type” electrochemical DNA biosensor for sensitive and specific analysis of a 250 bp unpurified PCR amplicon from the uidA gene of the E. coli genome. Asymmetric PCR was used to produce single-stranded PCR products. Streptavidin–polyHRP80 was employed to improve the signal gain during electrochemical detection. We optimized important experimental conditions for DNA sensing, including the streptavidin–polyHRP, the signal probe and the ion strength. Finally, we achieved a remarkable sensitivity of 10 fM synthetic DNA target, and successfully performed the analysis of PCR amplicons from as low as 0.2 pg μL−1 of E. coli genome. Compared with traditional single stranded DNA (ssDNA) probe based detection, our present work demonstrated 3 orders of magnitude improvement in sensitivity. In addition, our electrochemical DNA biosensor was 4 orders of magnitude more sensitive than normal electrophoretic analysis of PCR products. Our work made important progress in DNA nanostructured probe-based biosensors toward application in real applications. [ABSTRACT FROM AUTHOR]

There has been urgent demand for rapid, sensitive and cost-effective pesticide assay technologies due to the global attention of environmental and food-safety problems. Acetycholinesterase (AChE)-based electrochemical sensors have attracted significant interest toward this goal. In this contribution, we introduced multiwalled carbon nanotubes (MWNTs) into our sensor design, where they played dual enhancement roles; first is that MWNTs loaded on glassy carbon (GC) electrodes significantly increase surface areas, facilitating the electrochemical polymerization of prussian blue (PB), a redox mediator for the electrochemical oxidation of the enzymatic product, thiocholine (TCh). Second, MWNTs enhance the enzymatic activity of AChE, as manifested by the decreased Michaelis-Menten constant (K(m)). As a result of these two important enhancement factors offered by MWNTs, our electrochemical pesticide sensor exhibited rapid response and high sensitivity toward the detection of a series of pesticides. Moreover, we demonstrated that this sensor was stable, reproducible and selective enough for detection in real samples.