EFFECT OF TEMPERATURE ON OPTICAL-PROPERTIES OF REACTION CENTERS ORGANIZED IN LANGMUIR-BLODGETT-FILMS

Reaction centres (RC) isolated from Rhodobacter sphaeroides were arran ged in Langmuir-Blodgett (LB) film. The deposited layers were investig ated with a spectrophotometric assay after heating at different temper atures up to 473 K. The examination of the optical properties of RCs g ives a first indication of the molecule stability in the film after te mperature treatment. Comparisons of LB absorption spectra between film and solution after treatment at different temperatures were carried o ut. The absorbing bands of Bacteriopheophytin (Bphe), Bacteriochloroph yll (BChl) and Bacteriochlorophyll dimer (BChl(2)) were investigated. The results indicate that RCs which in the solution appear stable up t o 318 K maintain their absorption spectrum up to 358 K inside the film . The role of LB organization was checked by measuring the optical pro perties of non-oriented films after heating at different temperatures.