Optimization of metal-assisted chemical etching process in fabrication of p-type silicon wire arrays

The metal-assisted chemical etching (MCE) has attracted great attention because of the advantages such as simple and large area process, low-cost and compatible with existing semiconductor technology. We have achieved optimization conditions about two kinds of MCE method for fabrication of p-type silicon wire arrays. First one is one-step MCE that used AgNO3 and BOE solution and second is two-step MCE in which silicon etching proceeds by BOE and H 2O2 solution after depositing Au by thermal evaporation. Particularly, the effect of etching parameters, such as etching time and AgNO3 concentration in one-step MCE and metal catalyst thickness and etching solution temperature in two-step MCE on fabrication of silicon was investigated a morphology, length and etch rate of silicon wire. Finally, we have found important factors for fabrication of uniform and well aligned p-type silicon wire by MCE. © 2010 Published by Elsevier B.V. All rights reserved.1

Nanoelectrokinetic Selective Preconcentration Based on Ion Concentration Polarization

Nanoscale electrokinetic phenomenon called ion concentration polarization (ICP) has opened a new era in bio- and chemical-analysis platform due to its high efficiency and easy sample handling. In this review, the most recent advancements of selective preconcentration process using ICP were introduced. The flux balances of charged analytes were theoretically analyzed so that the behavior and the shape of preconcentrated plug were categorized into stacking/propagating and dumbbell/plug, respectively. The experimental demonstrations of these features were also given to verify the modeling. Furthermore, promising applications based on the analysis were described in this review. Lastly, future research direction would be suggested by elucidating pros and cons of ICP process.Y

Enhanced mitochondrial DNA editing in mice using nuclear-exported TALE-linked deaminases and nucleases

We present two methods for enhancing the efficiency of mitochondrial DNA (mtDNA) editing in mice with DddA-derived cytosine base editors (DdCBEs). First, we fused DdCBEs to a nuclear export signal (DdCBE-NES) to avoid off-target C-to-T conversions in the nuclear genome and improve editing efficiency in mtDNA. Second, mtDNA-targeted TALENs (mitoTALENs) are co-injected into mouse embryos to cleave unedited mtDNA. We generated a mouse model with the m.G12918A mutation in the MT-ND5 gene, associated with mitochondrial genetic disorders in humans. The mutant mice show hunched appearances, damaged mitochondria in kidney and brown adipose tissues, and hippocampal atrophy, resulting in premature death.11Nsciescopu

DCas9-mediated Nanoelectrokinetic Direct Detection of Target Gene for Liquid Biopsy

The-state-of-the-art bio- and nanotechnology have opened up an avenue to noninvasive liquid biopsy for identifying diseases from biomolecules in bloodstream, especially DNA. In this work, we combined sequence-specific-labeling scheme using mutated clustered regularly interspaced short palindromic repeats associated protein 9 without endonuclease activity (CRISPR/dCas9) and ion concentration polarization (ICP) phenomenon as a mechanism to selectively preconcentrate targeted DNA molecules for rapid and direct detection. Theoretical analysis on ICP phenomenon figured out a critical mobility, elucidating two distinguishable concentrating behaviors near a nanojunction, a stacking and a propagating behavior. Through the modulation of the critical mobility to shift those behaviors, the C-C chemokine receptor type 5 (CCR5) sequences were optically detected without PCR amplification. Conclusively, the proposed dCas9-mediated genetic detection methodology based on ICP would provide rapid and accurate micro/nanofluidic platform of liquid biopsies for disease diagnostics. © 2018 American Chemical Societ

dCas9-mediated nanoelectrokinetic direct detection of target gene for liquid biopsy

The-state-of-the-art bio- and nanotechnology have opened up an avenue to noninvasive liquid biopsy for identifying diseases from biomolecules in bloodstream, especially DNA. In this work, we combined sequence-specific-labeling scheme using mutated clustered regularly interspaced short palindromic repeats associated protein 9 without endonuclease activity (CRISPR/dCas9) and ion concentration polarization (ICP) phenomenon as a mechanism to selectively preconcentrate targeted DNA molecules for rapid and direct detection. Theoretical analysis on ICP phenomenon figured out a critical mobility, elucidating two distinguishable concentrating behaviors near a nanojunction, a stacking and a propagating behavior. Through the modulation of the critical mobility to shift those behaviors, the C-C chemokine receptor type 5 (CCR5) sequences were optically detected without PCR amplification. Conclusively, the proposed dCas9-mediated genetic detection methodology based on ICP would provide rapid and accurate micro/nanofluidic platform of liquid biopsies for disease diagnostics.