Liquid/liquid interfaces are recognized as specific 2 dimensional media, where various kinds of inhomogeneous catalytic reaction and molecular aggregation reactions can take place. Recently, we have found that the optical chirality of the protonated tetraphenylporphyrin aggregate formed at the interfaces of dodecane/sulfuric acid (4M) is remarkably affected by the chirality of co-existing counter anions or hydrophobic alcohols, which has been measured by an originally invented centrifugal liquid membrane (CLM) - circular dichroism method. The chirality of the interfacial molecular aggregates was also measured by a home built second harmonic generation – CD spectroscopy system, and a microscope version of CD and SHG-CD methods. Furthermore, we have invented a new method to measure the magnetic susceptibility of the liquid/liquid interface applying the magnetophoretic force generated by a magnetic field gradient of super conducting magnet (10T). From the magnetophoretic velocity of a micro-organic droplet including hydrophobic carboxylic acid in the aqueous solution of dilute paramagnetic Dy(III) ion, the interfacial magnetic susceptibility was determined, which afforded the interfacial concentration of Dy(III) at the interface. These new techniques will open new approaches in the study of colloid and surface science of soft materials.