Measurement of circular dichroism spectra of liquid/liquid interface by centrifugal liquid membrane method.

The direct measurement of the circular dichroism (CD) spectra of liquid/liquid interface has been achieved for the first time by the centrifugal liquid membrane (CLM) method combined with a conventional CD spectropolarimetry. In the sample chamber of the CD spectropolarimeter, a cylindrical glass cell containing small amounts of organic and aqueous phases was rotated at ca. 7000 rpm to generate a two-phase liquid membrane with a high specific interfacial area. The CD spectra of the J-aggregate of protonated 5,10,15,20-tetraphenylporphyrin formed at the toluene/sulfuric acid interface in the rotating cell have been measured. The results demonstrated the novelty and advantages of this method.