High-Density and Highly Surface Selective Adsorption of Protein–Nanoparticle Complexes by Controlling Electrostatic Interaction

Abstract: Herein, we designed and fabricated a hierarchically porous crosslinked polymeric microbead (PCP) with high density of functional groups for selective adsorption of cationic dyes from water. On account of...

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Development of Gold Nanoparticle Micropatterns for the Electrical Detection of Proteins

Nanomaterials ◽

10.3390/nano11020528 ◽

2021 ◽

Vol 11 (2) ◽

pp. 528

Author(s):

Geonwoo Lim ◽

Kibeom Kim ◽

Yuri Park ◽

Myoung-Hwan Park

Keyword(s):

Electrostatic Interaction ◽

Fluorescent Proteins ◽

Selective Adsorption ◽

Protein Detection ◽

Portable Equipment ◽

Simple Method ◽

Widespread Application ◽

Neutral Ligands ◽

Precise Interpretation ◽

Positively Charged

Protein analysis can be used to efficiently detect the early stages of various diseases. However, conventional protein detection platforms require expensive or complex equipment, which has been a major obstacle to their widespread application. In addition, uncertain signals from non-specific adhesion interfere with the precise interpretation of the results. To overcome these problems, the development of a technique that can detect the proteins in a simple method is needed. In this study, a platform composed of gold nanoparticles (GNPs) was fabricated through a simple imprinting method for protein detection. The corrugated surface naturally formed by the nanoparticle assemblies simultaneously increases the efficiency of adhesion and binding with analytes and reduces undesired interactions. After forming the GNP micropatterns, post-functionalization with both cationic and neutral ligands was performed on the surface to manipulate their electrostatic interaction with proteins. Upon protein binding, the change in the electrical values of the micropatterns was recorded by using a resistance meter. The resistance of the positively charged micropatterns was found to increase due to the electrostatic interaction with proteins, while no significant change in resistance was observed for the neutral micropatterns after immersion in a protein solution. Additionally, the selective adsorption of fluorescent proteins onto the micropatterns was captured using confocal microscopy. These simply imprinted GNP micropatterns are sensitive platforms that can detect various analytes by measuring the electrical resistance with portable equipment.

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High density hydrogen storage in nanocavities: Role of the electrostatic interaction

International Journal of Hydrogen Energy ◽

10.1016/j.ijhydene.2010.09.007 ◽

2010 ◽

Vol 35 (23) ◽

pp. 12864-12869 ◽

Cited By ~ 10

Author(s):

L. Reguera ◽

J. Roque ◽

J. Hernández ◽

E. Reguera

Keyword(s):

Hydrogen Storage ◽

Electrostatic Interaction ◽

High Density

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Grain-boundary-rich 2D materials for attomolar-ability biochemical sensors

10.21203/rs.3.rs-105060/v1 ◽

2020 ◽

Author(s):

Tianyu Xue ◽

Lixuan Liu ◽

Kun Ye ◽

Changqing Lin ◽

Zhiyan Jia ◽

...

Keyword(s):

Active Sites ◽

High Performance ◽

Selective Adsorption ◽

High Surface ◽

Layered Materials ◽

High Density ◽

Structural Defects ◽

Biochemical Sensors ◽

Sensor Performance ◽

2D Layered Materials

Abstract Next-generation high-performance biological and chemical sensors based on the emerging multitudinous two-dimensional (2D) layered materials have been attracting great attention in recent years. The performance of 2D biochemical sensors is strongly dependent on the structural defects, which provide indispensable active sites for sensitive and selective adsorption of analytes. However, achieving controllable defect engineering is still a big challenge. In the present work, we propose achieving superior biochemical sensor performance with high-surface-density grain boundaries (GBs), a kind of ubiquitous structural defects, in polycrystalline 2D thin films, which can be controllably synthesized. As a proof-of-concept, by utilizing the high-density GBs in monolayer (1L) WS2 films, we fabricated a series of surface plasmon resonance (SPR) sensors for mercury ion (Hg2+) detection. Our investigation has demonstrated substantial sensitivity enhancement of Hg2+ detection down to trace attomolar-level quantification (detection limit of 1 aM), which is ascribed to the abundance of active sites on high-density GBs. This work provides a promising avenue for the design of ultra-sensitive sensors toward commercialized products based on the GB-rich 2D layered materials.

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Planar defects in ordered (Ga,In)P

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100106570 ◽

1988 ◽

Vol 46 ◽

pp. 902-903

Author(s):

S. McKernan ◽

C. B. Carter ◽

D. Bour ◽

J. R. Shealy

Keyword(s):

Electron Diffraction ◽

Vapor Phase ◽

Growth Direction ◽

High Density ◽

Ordered Structure ◽

Planar Defects ◽

Diffraction Patterns ◽

Ternary Semiconductors ◽

Anion Species ◽

Metallic Vapor

The growth of ternary III-V semiconductors by organo-metallic vapor phase epitaxy (OMVPE) is widely practiced. It has been generally assumed that the resulting structure is the same as that of the corresponding binary semiconductors, but with the two different cation or anion species randomly distributed on their appropriate sublattice sites. Recently several different ternary semiconductors including AlxGa1-xAs, Gaxln-1-xAs and Gaxln1-xP1-6 have been observed in ordered states. A common feature of these ordered compounds is that they contain a relatively high density of defects. This is evident in electron diffraction patterns from these materials where streaks, which are typically parallel to the growth direction, are associated with the extra reflections arising from the ordering. However, where the (Ga,ln)P epilayer is reasonably well ordered the streaking is extremely faint, and the intensity of the ordered spot at 1/2(111) is much greater than that at 1/2(111). In these cases it is possible to image relatively clearly many of the defects found in the ordered structure.

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Quantitative defect studies in semiconductor TEM samples prepared by low angle ion milling

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100138932 ◽

1995 ◽

Vol 53 ◽

pp. 512-513

Author(s):

L. Mulestagno ◽

J.C. Holzer ◽

P. Fraundorf

Keyword(s):

Sample Preparation ◽

Milling Time ◽

High Density ◽

Low Density ◽

Ion Milling ◽

High Quality ◽

Variable Angle ◽

Major Disadvantage ◽

Induced Defects

Due to the wealth of information, both analytical and structural that can be obtained from it TEM always has been a favorite tool for the analysis of process-induced defects in semiconductor wafers. The only major disadvantage has always been, that the volume under study in the TEM is relatively small, making it difficult to locate low density defects, and sample preparation is a somewhat lengthy procedure. This problem has been somewhat alleviated by the availability of efficient low angle milling.Using a PIPS® variable angle ion -mill, manufactured by Gatan, we have been consistently obtaining planar specimens with a high quality thin area in excess of 5 × 104 μm2 in about half an hour (milling time), which has made it possible to locate defects at lower densities, or, for defects of relatively high density, obtain information which is statistically more significant (table 1).

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Atom-probe analysis of the solid-liquid interface

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100139755 ◽

1995 ◽

Vol 53 ◽

pp. 676-677

Author(s):

J.A. Panitz

Keyword(s):

Molecular Level ◽

Selective Adsorption ◽

Electronic Devices ◽

Atom Probe ◽

Chemical Agent ◽

Hostile Environment ◽

Solid Interface ◽

Solid Liquid Interface ◽

Solid Liquid ◽

Chemically Selective

The first few atomic layers of a solid can form a barrier between its interior and an often hostile environment. Although adsorption at the vacuum-solid interface has been studied in great detail, little is known about adsorption at the liquid-solid interface. Adsorption at a liquid-solid interface is of intrinsic interest, and is of technological importance because it provides a way to coat a surface with monolayer or multilayer structures. A pinhole free monolayer (with a reasonable dielectric constant) could lead to the development of nanoscale capacitors with unique characteristics and lithographic resists that surpass the resolution of their conventional counterparts. Chemically selective adsorption is of particular interest because it can be used to passivate a surface from external modification or change the wear and the lubrication properties of a surface to reflect new and useful properties. Immunochemical adsorption could be used to fabricate novel molecular electronic devices or to construct small, “smart”, unobtrusive sensors with the potential to detect a wide variety of preselected species at the molecular level. These might include a particular carcinogen in the environment, a specific type of explosive, a chemical agent, a virus, or even a tumor in the human body.

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Using the scanning electron microscope for failure analysis of high density magnetic media

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100126755 ◽

1987 ◽

Vol 45 ◽

pp. 392-393

Author(s):

Evelyn R. Ackerman ◽

Gary D. Burnett

Keyword(s):

Electron Microscope ◽

Scanning Electron Microscope ◽

Failure Analysis ◽

High Density ◽

Magnetic Media ◽

Specific Data ◽

Retrieval Systems ◽

Operating Environments ◽

The Media ◽

Scanning Electron

Advancements in state of the art high density Head/Disk retrieval systems has increased the demand for sophisticated failure analysis methods. From 1968 to 1974 the emphasis was on the number of tracks per inch. (TPI) ranging from 100 to 400 as summarized in Table 1. This emphasis shifted with the increase in densities to include the number of bits per inch (BPI). A bit is formed by magnetizing the Fe203 particles of the media in one direction and allowing magnetic heads to recognize specific data patterns. From 1977 to 1986 the tracks per inch increased from 470 to 1400 corresponding to an increase from 6300 to 10,800 bits per inch respectively. Due to the reduction in the bit and track sizes, build and operating environments of systems have become critical factors in media reliability.Using the Ferrofluid pattern developing technique, the scanning electron microscope can be a valuable diagnostic tool in the examination of failure sites on disks.

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