Zhang, Meiqin, Powell, Hayley V., Mackenzie, Stuart R. and Unwin, Patrick R. (2010) Kinetics of porphyrin adsorption and DNA-assisted desorption at the silica-water interface. Langmuir, Vol.26 (No.6). pp. 4004-4012. doi:10.1021/la903438p

Full text not available from this repository, contact author.

Request Changes to record.

Abstract

Evanescent wave cavity ring-down spectroscopy (EW-CRDS) has been used to study in situ the kinetics of the adsorption of 5,10,15,20-tetrakis(4-N-methylpyridiniumyl)porphyin (TMPyP) from pH 7.4 phosphate buffer solution (PBS) to the silica-water interface and the interaction of calf thymus DNA (CT-DNA) with the resulting TMPyP-functionalized Surface. TMPyP was delivered to the silica surface using an impinging jet technique to allow relatively fast surface kinetics to be accessed. Adsorption was first-order in TM PyP, and the initial adsorption rate constant at the bare surface was found to be k = (4.1 +/- 0.6) x 10(-2) cm s(-1). A deceleration in the adsorption kinetics was observed at longer times that could be described semiquantitatively using an Elovich-type kinetic expression. The limiting value of the absorbance corresponded approximately to monolayer coverage (6.2 x 10(13) molecules cm(-2)). Exposure of the TMPyP-modified silica surface to CT-DNA, achieved by flowing CT-DNA solution over the functionalizcd surface, resulted in efficient desorption of the TMPyP. The desorption process was driven by the interaction of TMPyP with CT-DNA, which UV-vis spectroscopy indicated involved intercalative binding. The desorption kinetics were also simulated using complementary finite element modeling of convection-diffusion coupled to a surface process.

Item Type:	Journal Article
Subjects:	Q Science > QD Chemistry T Technology > TA Engineering (General). Civil engineering (General)
Divisions:	Faculty of Science > Chemistry
Journal or Publication Title:	Langmuir
Publisher:	American Chemical Society
ISSN:	0743-7463
Official Date:	16 March 2010
Dates:	Date Event 16 March 2010 Published
Volume:	Vol.26
Number:	No.6
Number of Pages:	9
Page Range:	pp. 4004-4012
DOI:	10.1021/la903438p
Status:	Peer Reviewed
Publication Status:	Published
Access rights to Published version:	Restricted or Subscription Access
Funder:	Marie Curie Incoming International Fellowship, European Commission, Engineering and Physical Sciences Research Council (EPSRC), Advanced Research Fellowship, European Regional Development Fund (ERDF)
Grant number:	040126: "SECM-CRDS", EP/C00907X (EPSRC)

Data sourced from Thomson Reuters' Web of Knowledge

Request changes or add full text files to a record

Repository staff actions (login required)

View Item