Search

Your search keyword '"Fielden, Peter R."' showing total 342 results
Start Over Author "Fielden, Peter R."
342 results on '"Fielden, Peter R."'

13. Isotachophoresis on Planar Polymeric Substrates

Author

Baldock, Sara J, Bektas, Nihal, Fielden, Peter R, Goddard, Nicholas J, Pickering, Lynsay W, Prest, Jeffrey E, Snook, Richard D, Brown, Bernard J Treves, Vaireanu, Danut I, Harrison, D. Jed, editor, and van den Berg, Albert, editor

Published
1998
Full Text
View/download PDF

16. Using Fourier transform IR spectroscopy to analyze biological materials

Author

Baker, Matthew J, Trevisan, Júlio, Bassan, Paul, Bhargava, Rohit, Butler, Holly J, Dorling, Konrad M, Fielden, Peter R, Fogarty, Simon W, Fullwood, Nigel J, Heys, Kelly A, Hughes, Caryn, Lasch, Peter, Martin-Hirsch, Pierre L, Obinaju, Blessing, Sockalingum, Ganesh D, Sulé-Suso, Josep, Strong, Rebecca J, Walsh, Michael J, Wood, Bayden R, Gardner, Peter, and Martin, Francis L

Published
2014
Full Text
View/download PDF

32. Optical leaky waveguide sensor for detection of bacteria with ultrasound attractor force

Author

Zourob, Mohammed, Hawkes, Jeremy J., Coakley, W. Terence, Brown, Bernard J. Treves, Fielden, Peter R., McDonnell, Martin B., and Goddard, Nicholas J.

Subjects
Optical waveguides -- Usage, Bacterial cell walls -- Research, Bacillus subtilis -- Research, Chemistry
Abstract

An integrated, sensitive, and rapid system was developed for the detection of bacteria. The system combined an optical metal-clad leaky waveguide (MCLW) sensor with ultrasound standing waves (USW). The performance of a MCLW sensor for the detection of bacteria has been increased (> 100 fold) by using USWs to drive bacteria onto the sensor surface. By forming the USW nodes at or within the surface of the MCLW, the diffusion-limited capture rate has been replaced by fast movement. Immobilized anti-BG antibody on the MCLW sensor surface was used to capture Bacillus subtilis var. niger (BG) bacterial spores driven to the surface. This combination of sensor and attractor force combination has been tested by detecting the evanescent scattering from bacterial spores at the sensor surface. Application of ultrasound for 3 min gave a detection limit for BG bacterial spores of 1 x [10.sup.3] spores/mL.

Published
2005

33. An integrated metal clad leaky waveguide sensor for detection of bacteria

Author

Zourob, Mohammed, Mohr, Stephan, Brown, Bernard J. Treves, Fielden, Peter R., McDonnell, Martin B., and Goddard, Nicholas J.

Subjects
Optical detectors -- Usage, Waveguides -- Usage, Bacteria -- Testing, Chemistry
Abstract

An integrated optical metal clad leaky waveguide (MCLW) sensor device has been developed for the detection of bacteria. This is more sensitive than waveguide sensors currently in use. The MCLW device has been fabricated to extend the evanescent field to provide significant light intensity over the entire volume of the bacteria bound on the chip surface within this field. This in turn increases the interaction of the light with the entire volume of the bacteria. MCLW devices have been used for detecting refractive index changes, scattering, and fluorescence from bacterial spores captured on an immobilized antibody. The detection limit of Bacillus subtilis var. niger bacterial spores using refractive index detection was 8 x [10.sup.4] spores/mL. The scattering intensity of the BG spores was found to be three times greater than the scattering intensity generated using surface plasmon resonance. The extended light propagation along the direction of flow for a few millimeters provides an effective interrogation approach to increase the area of detection to detect low concentrations down to 1 x [10.sup.4] spores/mL. The sensor was then optimized by studying the key factors affecting sensor performance including changing the pH of the medium, type of antibody immobilization matrix, sensor surface regeneration approaches, and longevity of the sensor.

Published
2005

35. Fabrication of a spectrophotometric absorbance flow cell using injection-molded plastic

Author

Hulme, John P., Fielden, Peter R., and Goddard, Nicholas J.

Subjects
Spectrophotometry, Chemistry
Abstract

A microfluidic device with integrated spectrophotometric elements has been injection molded in poly(methyl methacrylate) (PMMA). The strategy for producing the device combined the direct photopatterning, replica molding techniques and a rapid cooled release mechanism in conjunction with material-material transfer to form a multilayer epoxy master on an injection mold insert. An injection-molded flow cell consisting of 1800 diffractive elements patterned on 25-[micro]m-high PMMA pillars was produced. The design incorporated a large cross sectional surround, simplifying the alignment and bonding procedure. The absorbance range of one of the devices was standardized against a commercially available visible spectrophotometer at 605 nm to increasing concentrations of Nile blue perchlorate A dye in aqueous solution. The detection limit for a new integrated device was 1.2 x [10.sup.-6] m/Lof the mentioned dye.

Published
2004

48. Toward a microfluidic-based rapid amylase assay system

Author

Holmes, Richard J., Summersgil, Philip, Ryan, Timothy, Brown, Bernard J. Treves, Mockbil, Amal, Grieve, Bruce D., and Fielden, Peter R.

Subjects
Amylases -- Chemical properties, Fluid dynamics -- Analysis, Hydrolysis -- Analysis, Business, Food/cooking/nutrition
Published
2009

50. Using Fourier transform IR spectroscopy to analyze biological materials

Author

Baker, Matthew J., Trevisan, Júlio, Bassan, Paul, Bhargava, Rohit, Butler, Holly J., Dorling, Konrad M., Fielden, Peter R., Fogarty, Simon W., Fullwood, Nigel J., Heys, Kelly A., Hughes, Caryn, Lasch, Peter, Martin-Hirsch, Pierre L., Obinaju, Blessing, Sockalingum, Ganesh D., Sulé-Suso, Josep, Strong, Rebecca, Walsh, Michael J., Wood, Bayden R., Gardner, Peter, Martin, Francis L., Baker, Matthew J., Trevisan, Júlio, Bassan, Paul, Bhargava, Rohit, Butler, Holly J., Dorling, Konrad M., Fielden, Peter R., Fogarty, Simon W., Fullwood, Nigel J., Heys, Kelly A., Hughes, Caryn, Lasch, Peter, Martin-Hirsch, Pierre L., Obinaju, Blessing, Sockalingum, Ganesh D., Sulé-Suso, Josep, Strong, Rebecca, Walsh, Michael J., Wood, Bayden R., Gardner, Peter, and Martin, Francis L.

Abstract

IR spectroscopy is an excellent method for biological analyses. It enables the nonperturbative, label-free extraction of biochemical information and images toward diagnosis and the assessment of cell functionality. Although not strictly microscopy in the conventional sense, it allows the construction of images of tissue or cell architecture by the passing of spectral data through a variety of computational algorithms. Because such images are constructed from fingerprint spectra, the notion is that they can be an objective reflection of the underlying health status of the analyzed sample. One of the major difficulties in the field has been determining a consensus on spectral pre-processing and data analysis. This manuscript brings together as coauthors some of the leaders in this field to allow the standardization of methods and procedures for adapting a multistage approach to a methodology that can be applied to a variety of cell biological questions or used within a clinical setting for disease screening or diagnosis. We describe a protocol for collecting IR spectra and images from biological samples (e.g., fixed cytology and tissue sections, live cells or biofluids) that assesses the instrumental options available, appropriate sample preparation, different sampling modes as well as important advances in spectral data acquisition. After acquisition, data processing consists of a sequence of steps including quality control, spectral pre-processing, feature extraction and classification of the supervised or unsupervised type. A typical experiment can be completed and analyzed within hours. Example results are presented on the use of IR spectra combined with multivariate data processing.

Published
2014

Catalog

Books, media, physical & digital resources
See catalog results