ArcDia TPX -technology for single-step bioaffinity assays

The objective of the R&D work around two-photon fluorescence excitation in our laboratory has been to develop a new methodology and instrumentation for in vitro diagnostics and in more general, for biomedical analysis with labelled bioaffinity reagents. The ArcDia TPX -technology (two-photon fluorescence excitation microparticle fluorometry) is based on two-photon excitation of fluorescence and on the use of latex microparticles as solid phase.

The ArcDia TPX-technology offers many advantages if compared with the conventional methods:

Single step assay, separation free High sensitivity, positive signal response – high dynamic range Sensitivity is independent on the volume, small sample and reagent volumes Allows on-line monitoring of the reaction kinetics Simultaneous monitoring of multiple parameters in same reaction volume Compact and inexpensive instrumentation Improves the laboratory cost-efficiency considerably

A fully automated ArcDia TPX in-vitro diagnostics system is much simpler, smaller and less expensive than the conventional automatic systems today. Because this system is based on the single-step ArcDia TPX-technology, no separation steps nor such functions are needed. The multiparametricity means, that there is no need to load in reagents for several different assays separately and there is no need for dedicated dispensing means. Conventional test kits with coated tubes are not needed either. The waste of material and especially packaging material waste is reduced. The compact size and lower unit price support the idea of purchasing a separate unit for each assay panel. We have ArcDia TPX fluorometers available for developement of TPX-assays

Further development of laser and dye technology ables us to detect with ArcDia TPX-technology even single molecule complexes such as e.g. complexes of antibody and antigen as well as their formation and reaction kinetics directly in the solution without any solid phase. This “molecule counting” technology is based on photon burst analysis or fluorescence correlation spectroscopy and it has many research and routine applications. Similar techniques are currently being developed also for HTS (high throughput screening) in the field of drug discovery.

Licences for ArcDia TPX-technology is offered to domestic and foreign in-vitro diagnostics industry. Patents pending.

Development of ArcDia TPX-technology has been supported by Academy of Finland and National Technology Agency Tekes.