Publications by authors named "W T Ashurst"

Exploiting cellulose nanocrystals' high aspect ratio and tailorable surface for immunological biosensors has been hindered by the relatively limited research on using commonly available sulfated cellulose nanocrystals (CNCs) for antibody immobilization and by the low hydrolytic stability of dried assemblies produced from sulfated CNCs. Herein, we report a reaction scheme that enables both hydrolytic stability and antibody immobilization through 3-aminopropyl-triethoxysilane and glutaric anhydride chemistry. Immobilization was demonstrated using three model antibodies used in the detection of the cancer biomarkers: alpha-fetoprotein, prostate-specific antigen, and carcinoembryonic antigen.

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Microelectromechanical systems (MEMS) have become a ubiquitous part of a multitude of industries including transportation, communication, medical, and consumer products. The majority of commercial MEMS devices are produced from silicon using energy-intensive and harsh chemical processing. We report that actuatable standard MEMS devices such as cantilever beam arrays, doubly clamped beams, residual strain testers, and mechanical strength testers can be produced via low-temperature fabrication of shear-aligned cellulose nanocrystal (CNC) films.

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It is well known that the environment in which micromechanical systems operate significantly affects their performance. It is, therefore, important to characterize micromachine behavior in environments where the humidity, pressure, and chemical composition of the ambient can be precisely controlled. Achieving such a level of environmental control presents significant challenges in view of the required instrumentation.

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Digital phase-shifting interferometry (PSI), a technique widely used in optical testing, requires interferograms collected at optical phase differences separated by a definite phase step. The five-frame interferogram-collecting sequence suggested by Hariharan et al. [Appl.

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Dodecanethiol-stabilized gold nanoparticles (AuNPs) were deposited via a gas-expanded liquid (GXL) technique utilizing CO(2)-expanded hexane onto substrates of different surface energy. The different surface energies were achieved by coating silicon (100) substrates with various organic self-assembled monolayers (SAMs). Following the deposition of AuNP films, the films were characterized to determine the effect of substrate surface energy on nanoparticle film deposition and growth.

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