A comparative study of spectral and angle-dependent SPR devices in biological applications

A planar surface plasmon resonance sensor for the real time monitoring of b iochemical interaction is described. The SPR signal is detected by spectral interrogation as a resonance wavelength shift. The resulting angle-indepen dent detection is less prone to interferences by vibrations. The architectu re of the device allows a further miniaturization. This is a requirement fo r the construction of portable SPR-devices which can be used for onsite ana lysis. In this paper we report on the performance of our detector in two pr actical applications: (i) a competitive immunoassay for the detection of th e antithrombolytical protein staphylokinase and (ii) the detection of the e ndoproteolytic enzyme IgAse. Both applications are of relevance to the clin ical laboratory and cover important subjects of biomolecular interaction an alysis. Similar experiments were also carried out on a BIAcore2000 instrume nt. We can therefore discuss the advantages and limitations of our SPR-devi ce in a direct comparison with a high end instrument. Our data show that ou r detector design does meet major requirements for the development of small er portable SPR-devices. (C) 1998 Elsevier Science S.A. All rights reserved .