Polyelectrolyte layer-by-layer self-assembly enhanced by electric field and their multilayer membranes for separating isopropanol–water mixtures

Candida-associated denture stomatitis (CADS) is a common, recurring clinical complication in denture wearers that can lead to serious oral and systemic health problems. Polyelectrolyte layer-by-layer (LBL) self-assembly technology on denture materials offers a new design principle for controlling fungal biofilm formation.

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Electric-Field-Directed Self-Assembly of Active Enzyme-Nanoparticle Structures

Journal of Biomedicine and Biotechnology ◽

10.1155/2012/178487 ◽

2012 ◽

Vol 2012 ◽

pp. 1-9 ◽

Cited By ~ 3

Author(s):

Alexander P. Hsiao ◽

Michael J. Heller

Keyword(s):

Electric Field ◽

Self Assembly ◽

Microelectrode Array ◽

Glucose Sensor ◽

Directed Assembly ◽

Passive Layer ◽

Higher Order ◽

Significant Loss ◽

Layer By Layer ◽

Multilayered Structures

A method is presented for the electric-field-directed self-assembly of higher-order structures composed of alternating layers of biotin nanoparticles and streptavidin-/avidin-conjugated enzymes carried out on a microelectrode array device. Enzymes included in the study were glucose oxidase (GOx), horseradish peroxidase (HRP), and alkaline phosphatase (AP); all of which could be used to form a light-emitting microscale glucose sensor. Directed assembly included fabricating multilayer structures with 200 nm or 40 nm GOx-avidin-biotin nanoparticles, with AP-streptavidin-biotin nanoparticles, and with HRP-streptavidin-biotin nanoparticles. Multilayered structures were also fabricated with alternate layering of HRP-streptavidin-biotin nanoparticles and GOx-avidin-biotin nanoparticles. Results showed that enzymatic activity was retained after the assembly process, indicating that substrates could still diffuse into the structures and that the electric-field-based fabrication process itself did not cause any significant loss of enzyme activity. These methods provide a solution to overcome the cumbersome passive layer-by-layer assembly methods to efficiently fabricate higher-order active biological and chemical hybrid structures that can be useful for creating novel biosensors and drug delivery nanostructures, as well as for diagnostic applications.

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Novel Fluorescent Labels Prepared by Layer-by-Layer Assembly on Colloids for Biodetection Systems

MRS Proceedings ◽

10.1557/proc-667-g5.5 ◽

2001 ◽

Vol 667 ◽

Author(s):

Wenjun Yang ◽

Dieter Trau ◽

Reinhard Renneberg ◽

Nai-Teng Yu ◽

Frank Caruso

Keyword(s):

Fluorescence Intensity ◽

Immunoglobulin G ◽

Self Assembly ◽

Film Growth ◽

Layer By Layer ◽

Microscopic Image ◽

Assembly Method ◽

Polyelectrolyte Layer ◽

Polystyrene Microparticles ◽

Layer Assembly

ABSTRACTFluorescent polystyrene microparticles with different sizes were produced by the consecutive assembly of fluorescently labeled polyelectrolytes using the layer-by-layer self-assembly method. Film growth was characterized by microelectrophoresis and fluorescence microscopic image (FMI) analysis. Alternating negative and positive ζ-potentials with deposition of each successive polyelectrolyte layer demonstrated that the alternate adsorption of polyelectrolytes was achieved. FMI analysis provided direct measurement of the fluorescence intensity of single microparticles. The subsequent deposition of a protein (immunoglobulin G, IgG) layer onto the fluorescent microparticles was confirmed by a sandwich immunoassay.

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