[LINK] Re: RFID in Govt, and in People

[stephen at melbpc.org.au]

At 05:38 PM 5/10/2006, Geoff Ramadan wrote:

> Short range RFID tags .. typically 5 to 10cm read range.
> ... The read range is limited by design (antenna / power)

Recent research, (published next Wednesday) indicates that DNA 
electromagnetic intensity will vary with Au/Ag metal proximity:

1: Journal American Chemical Society.  2006  Oct 11th   www.pubmed.com

Distance-dependent emission from dye-labeled oligonucleotides on striped 
au/ag nanowires..

Stoermer RL, Keating CD.  Contribution from the Department of Chemistry, 
The Pennsylvania State University.

When fluorescently tagged oligo-nucleotides are located near metal 
surfaces, their emission intensity is impacted by both electromagnetic 
effects (i.e., quenching and / or enhancement of emission) and the 
structure of the nucleic acids (e.g., random coil, hairpin, or duplex).

. Nanowires containing identifiable patterns of Au and Ag segments were 
used as the metal substrates in this work, which enabled us to directly 
compare .. differences in emission .. (found) highly sensitive to 
hybridization efficiency, due to substantial changes in DNA extension .. 

Differences in fluorescence patterning on Au and Ag were noted as a 
function of ..chromophore identity.. For example, emission intensity for 
TAMRA-labeled oligonucleotides changed ..

We also observed fluorescence enhancement at the ends of nanowires and at 
(probe)surface defects where heightened electromagnetic fields affect the 
fluorescence.  

PM ID: 17017805 [PubMed - in process] 
--

Cheers all ..
Stephen Loosley
Melbourne, Australia