| Time-Gated Luminescence Microscopy Allowing Direct Visual Inspection of Lanthanide-Stained Microorganisms in Background-Free Condition. | |
| | |
MedLine Citation:
|
PMID: 21344865 Owner: NLM Status: Publisher |
Abstract/OtherAbstract:
|
Application of standard immuno-fluorescence microscopy techniques for detection of rare-event microorganisms in dirty samples is severely limited by autofluorescence of nontarget organisms or other debris. Time-gated detection using gateable array detectors in combination with microsecond-lifetime luminescent bioprobes (usually lanthanide-based) is highly effective in suppression of (nanosecond-lifetime) autofluorescence background; however, the complexity and cost of the instrumentation is a major barrier to application of these techniques to routine diagnostics. We report a practical, low-cost implementation of time-gated luminescence detection in a standard epifluorescence microscope which has been modified to include a high-power pulsed UV light-emitting diode (LED) illumination source and a standard fast chopper inserted in the focal plane behind a microscope eyepiece. Synchronization of the pulsed illumination/gated detection cycle is driven from the clock signal from the chopper. To achieve time-gated luminescence intensities sufficient for direct visual observation, we use high cycle rates, up to 2.5 kHz, taking advantage of the fast switching capabilities of the LED source. We have demonstrated real-time direct-visual inspection of europium-labeled Giardia lamblia cysts in dirty samples and Cryptosporidium parvum oocysts in fruit juice concentrate. The signal-to-background ratio has been enhanced by a factor of 18 in time-gated mode. The availability of low-cost, robust time-gated microscopes will aid development of long-lifetime luminescence bioprobes and accelerate their application in routine laboratory diagnostics. |
| | |
Authors:
|
Dayong Jin; James A Piper |
Related Documents
:
|
8155845 - Holobionts, hybrids, and cladistic classification. 11777385 - (13)c nuclear magnetic relaxation study of segmental dynamics of the heteropolysacchari... 15241405 - Prediction of emperor-hawaii seamount locations from a revised model of global plate mo... 811985 - Light-chain nephropathy. renal tubular dysfunction associated with light-chain proteinu... 16933425 - Perceiving depth in point-light actions. 10757485 - Effects of trap design and co2 presentation on the measurement of adult mosquito abunda... |
Publication Detail:
|
Type: JOURNAL ARTICLE Date: 2011-2-23 |
Journal Detail:
|
Title: Analytical chemistry Volume: - ISSN: 1520-6882 ISO Abbreviation: - Publication Date: 2011 Feb |
Date Detail:
|
Created Date: 2011-2-24 Completed Date: - Revised Date: - |
Medline Journal Info:
|
Nlm Unique ID: 0370536 Medline TA: Anal Chem Country: - |
Other Details:
|
Languages: ENG Pagination: - Citation Subset: - |
Affiliation:
|
Advanced Cytometry Laboratories at Macquarie, MQ Biofocus Research Centre, Faculty of Science, Macquarie University , NSW 2109 Australia. |
Export Citation:
|
APA/MLA Format Download EndNote Download BibTex |
| MeSH Terms | |
Descriptor/Qualifier:
|
|
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine
Previous Document: Simultaneous detection of single molecules and singulated ensembles of molecules enables immunoassay...
Next Document: Generating nonlinear concentration gradients in microfluidic devices for cell studies.