Linked Life Data

19628383

Source:http://linkedlifedata.com/resource/pubmed/id/19628383

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2009-8-11
pubmed:abstractText
A primary advantage of label-free detection methods over fluorescent measurements is its quantitative detection capability, since an absolute measure of adsorbed material facilitates kinetic characterization of biomolecular interactions. Interferometric techniques relate the optical phase to biomolecular layer density on the surface, but the conversion factor has not previously been accurately determined. We present a calibration method for phase shift measurements and apply it to surface-bound bovine serum albumin, immunoglobulin G, and single-stranded DNA. Biomolecules with known concentrations dissolved in salt-free water were spotted with precise volumes on the array surface and upon evaporation of the water, left a readily calculated mass. Using our label-free technique, the calculated mass of the biolayer was compared with the measured thickness, and we observed a linear dependence over 4 orders of magnitude. We determined that the widely accepted conversion of 1 nm of thickness corresponds to approximately 1 ng/mm(2) surface density held reasonably well for these substances and through our experiments can now be further specified for different types of biomolecules. Through accurate calibration of the dependence of thickness on surface density, we have established a relation allowing precise determination of the absolute number of molecules for single-stranded DNA and two different proteins.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
1873-4235
pubmed:author
pubmed:issnType
Electronic
pubmed:day
15
pubmed:volume
25
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
167-72
pubmed:dateRevised
2010-9-16
pubmed:meshHeading
pubmed:year
2009
pubmed:articleTitle
Quantification of DNA and protein adsorption by optical phase shift.
pubmed:affiliation
Department of Electrical & Computer Engineering, Boston University, 8 St. Mary's Street, Boston, MA 02215, USA.
pubmed:publicationType
Journal Article, Evaluation Studies