Long-range surface plasmons for high-resolution surface plasmon resonance sensors

We present the application of long-range surface plasmons to a wavelength-m odulated surface plasmon resonance sensor. Theoretical design parameters an d experimental data are presented for two sensor designs, using either magn esium fluoride or Teflon AF-1600 as a dielectric buffer layer. The demonstr ated sensitivity of the long-range surface plasmon resonance sensor in refr actometric experiments is up to seven times higher than that of an equivale nt conventional surface plasmon resonance (SPR) sensor, while the measured resolution is comparable. According to theoretical design calculations pres ented, further optimization of materials and layer thickness could reduce t he resonance width while achieving even higher sensitivities, thereby creat ing a sensor with significantly better resolution than conventional SPR sen sors. (C) 2001 Elsevier Science B.V. All rights reserved.