Extremely sensitive and wide-range silver ion detection via assessing the integrated surface potential of a DNA-capped gold nanoparticle

Biomimetically Engineered Amyloid-Shelled Gold Nanocomplexes for Discovering α-Synuclein Oligomer-Degrading Drugs

The assembly of α-synuclein (αS) oligomers is recognized as the main pathological driver of synucleinopathies. While the elimination of toxic αS oligomers shows promise for the treatment of Parkinson's disease (PD), the discovery of αS oligomer degradation drugs has been hindered by the lack of proper drug screening tools. Here, we report a drug screening platform for monitoring the efficacy of αS-oligomer-degrading drugs using amyloid-shelled gold nanocomplexes (ASGNs). We fabricate ASGNs in the presence of dopamine, mimicking the in vivo generation process of pathological αS oligomers. To test our platform, the first of its kind for PD drugs, we use αS-degrading proteases and various small molecular substances that have shown efficacy in PD treatment. We demonstrate that the ASGN-based in vitro platform has strong potential to discover effective αS-oligomer-targeting drugs, and thus it may reduce the attrition problem in drug discovery for PD treatment.

Melanoma Detection by AFM Indentation of Histological Specimens

Melanoma is visible unlike other types of cancer, but it is still challenging to diagnose correctly because of the difficulty in distinguishing between benign nevus and melanoma. We conducted a robust investigation of melanoma, identifying considerable differences in local elastic properties between nevus and melanoma tissues by using atomic force microscopy (AFM) indentation of histological specimens. Specifically, the histograms of the elastic modulus of melanoma displayed multimodal Gaussian distributions, exhibiting heterogeneous mechanical properties, in contrast with the unimodal distributions of elastic modulus in the benign nevus. We identified this notable signature was consistent regardless of blotch incidence by sex, age, anatomical site (e.g., thigh, calf, arm, eyelid, and cheek), or cancer stage (I, IV, and V). In addition, we found that the non-linearity of the force-distance curves for melanoma is increased compared to benign nevus. We believe that AFM indentation of histological specimens may technically complement conventional histopathological analysis for earlier and more precise melanoma detection.

A review on silver-mediated DNA base pairs: methodology and application

The investigation of the interaction between metal ions and DNA has always attracted much attention in the fields of bioinorganic chemistry, supramolecular coordination chemistry, and DNA nanotechnology. Its mode of action can be simply divided into two aspects. On the one hand, it is non-specific electrostatic adsorption, mainly including Na⁺, K⁺, Mg²⁺, Ca²⁺ and other physiologically regulating ions; on the other hand, it is specific covalent binding, such as Pt²⁺, Hg²⁺, Ag⁺ and other heavy metal ions. This article focuses on the mechanism of action between Ag⁺ and DNA mismatch pair C-C, and summarizes its main characterization methods and various applications. It aims to provide a certain reference for the field of biological devices. With the development of cryo-electron microscopy and liquidcell TEM, the structure of C-Ag⁺-C is expected to be further characterized, which will be more widely used.

Application of DNA-Nanosensor for Environmental Monitoring: Recent Advances and Perspectives

PURPOSE OF REVIEW

Environmental pollutants are threat to human beings. Pollutants can lead to human health and environment hazards. The purpose of this review is to summarize the work done on detection of environmental pollutants using DNA nanosensors and challenges in the areas that can be focused for safe environment.

RECENT FINDINGS

Most of the DNA-based nanosensors designed so far use DNA as recognition element. ssDNA, dsDNA, complementary mismatched DNA, aptamers, and G-quadruplex DNA are commonly used as probes in nanosensors. More and more DNA sequences are being designed that can specifically detect various pollutants even simultaneously in complex milk, wastewater, soil, blood, tap water, river, and pond water samples. The feasibility of direct detection, ease of designing, and analysis makes DNA nanosensors fit for future point-of-care applications.

SUMMARY

DNA nanosensors are easy to design and have good sensitivity. DNA component and nanomaterials can be designed in a controlled manner to detect various environmental pollutants. This review identifies the recent advances in DNA nanosensor designing and opportunities available to design nanosensors for unexplored pathogens, antibiotics, pesticides, GMO, heavy metals, and other toxic pollutant.

Role of gold nanoparticles in advanced biomedical applications

Gold nanoparticles (GNPs) have generated keen interest among researchers in recent years due to their excellent physicochemical properties. In general, GNPs are biocompatible, amenable to desired functionalization, non-corroding, and exhibit size and shape dependent optical and electronic properties. These excellent properties of GNPs exhibit their tremendous potential for use in diverse biomedical applications. Herein, we have evaluated the recent advancements of GNPs to highlight their exceptional potential in the biomedical field. Special focus has been given to emerging biomedical applications including bio-imaging, site specific drug/gene delivery, nano-sensing, diagnostics, photon induced therapeutics, and theranostics. We have also elaborated on the basics, presented a historical preview, and discussed the synthesis strategies, functionalization methods, stabilization techniques, and key properties of GNPs. Lastly, we have concluded this article with key findings and unaddressed challenges. Overall, this review is a complete package to understand the importance and achievements of GNPs in the biomedical field.

DNA-Based Fabrication for Nanoelectronics

The bottom-up DNA-templated nanoelectronics exploits the unparalleled self-assembly properties of DNA molecules and their amenability with various types of nanomaterials. In principle, nanoelectronic devices can be bottom-up assembled with near-atomic precision, which compares favorably with well-established top-down fabrication process with nanometer precision. Over the past decade, intensive effort has been made to develop DNA-based nanoassemblies including DNA-metal, DNA-polymer, and DNA-carbon nanotube complexes. This review introduces the history of DNA-based fabrication for nanoelectronics briefly and summarizes the state-of-art advances of DNA-based nanoelectronics. In particular, the most widely applied characterization techniques to explore their unique electronic properties at the nanoscale are described and discussed, including scanning tunneling microscopy, conductive atomic force microscopy, and Kelvin probe force microscopy. We also provide a perspective on potential applications of DNA-based nanoelectronics.