Immobilisation of solvatochromic dyes on transparent cellulose films; an improved methodology for the study of homeopathic potencies

ABSTRACT

Highly diluted and succussed solutions (homeopathic potencies) have been shown to interact with a wide range of solvatochromic dyes based on changes in their UV-visible spectra. Studies so far have involved free dyes in solution, but there is a pressing need to find ways to investigate the potency-dye interaction using isolated dye molecules in order to ask more searching physico-chemical questions regarding the fundamental nature of potencies. Aims and Methods:The aims of the present study have been tolook for ways to covalently immobilizesolvatochromic dyes onto transparent cellulose films and hence be in a position to investigate dye-potency interactions without the complication of dye-dye interactions, including dye aggregation, which can occur with free dyes in solution. Results: to date a total of nine different dyes have been immobilised on cellulose films using epoxide activation of hydroxyl groups on the cellulose surface. Using this methodology studies have begun looking at the time course of potency action on one of these immobilised dyes, Brooker's merocyanine. Results show that the interaction ofArsenicum10M with this dye consists of three phases ­an initial growth phase, a sustained plateau of interaction and a final decline phase lasting several days.Conclusions: amethodology has been developed that successfully immobilises solvatochromic dyes onto transparent cellulose film. These films can then be used in a spectrophotometer to study at a much more detailed level how potencies interact with dyes compared with using free dyes in solution. Results indicate that the information gained in this way provides new insights regarding the fundamental nature of potencies. Specifically, studies using immobilised Brooker's merocyanine with Arsenicum10M reveal that the lifetime of the potency is much longer than expected and that its action consists of three distinct phases, suggesting a resonant interaction with the dye.