Articles by Joseph Hosford in JoVE
Large-area Scanning Probe Nanolithography Facilitated by Automated Alignment and Its Application to Substrate Fabrication for Cell Culture Studies I-Ning Lee*1,2, Joseph Hosford*1, Shuai Wang3, John A. Hunt4, Judith M. Curran2, William P. Heath3, Lu Shin Wong1 1Manchester Institute of Biotechnology & School of Chemistry, University of Manchester, 2School of Engineering, University of Liverpool, 3School of Electrical and Electronic Engineering, University of Manchester, 4School of Science and Technology, Nottingham Trent University Here we present a protocol for wide-area scanning probe nanolithography enabled by the iterative alignment of probe arrays, as well as the utilization of lithographic patterns for cell-surface interaction studies.
Other articles by Joseph Hosford on PubMed
A High-throughput Assay for Arylamine Halogenation Based on a Peroxidase-mediated Quinone-amine Coupling with Applications in the Screening of Enzymatic Halogenations Chemistry (Weinheim an Der Bergstrasse, Germany). | Pubmed ID: 25319801 Arylhalides are important building blocks in many fine chemicals, pharmaceuticals and agrochemicals, and there has been increasing interest in the development of more "green" halogenation methods based on enzyme catalysis. However, the screening and development of new enzymes for biohalogenation has been hampered by a lack of high-throughput screening methods. Described herein is the development of a colorimetric assay for detecting both chemical and enzymatic arylamine halogenation reactions in an aqueous environment. The assay is based on the unique UV/Vis spectrum created by the formation of an ortho-benzoquinone-amine adduct, which is produced by the peroxidase-catalysed benzoquinone generation, followed by Michael addition of either a halogenated or non-halogenated arylamine. This assay is sensitive, rapid and amenable to high-throughput screening platforms. We have also shown this assay to be easily coupled to a flavin-dependent halogenase, which currently lacks any convenient colorimetric assay, in a "one-pot" workflow.
Parallelized Biocatalytic Scanning Probe Lithography for the Additive Fabrication of Conjugated Polymer Structures Nanoscale. | Pubmed ID: 29620786 Scanning probe lithography (SPL) offers a more accessible alternative to conventional photolithography as a route to surface nanofabrication. In principle, the synthetic scope of SPL could be greatly enhanced by combining the precision of scanning probe systems with the chemoselectivity offered by biocatalysis. This report describes the development of multiplexed SPL employing probes functionalized with horseradish peroxidase, and its subsequent use for the constructive fabrication of polyaniline features on both silicon oxide and gold substrates. This polymer is of particular interest due to its potential applications in organic electronics, but its use is hindered by its poor processability, which could be circumvented by the direct in situ synthesis at the desired locations. Using parallelized arrays of probes, the lithography of polymer features over 1 cm2 areas was achieved with individual feature widths as small as 162 ± 24 nm. The nature of the deposited materials was confirmed by Raman spectroscopy, and it was further shown that the features could be chemically derivatized postlithographically by Huisgen [2 + 3] "click" chemistry, when 2-propargyloxyaniline was used as the monomer in the initial lithography step.