The RLS spectra of the system are shown in Fig. 2. It can be known that the RLS signal of IPTP solution is weak in the absence of thorium (IV). When IPTP reacts with thorium (IV) to form supramolecular polymer, there is significantly enhance in the RLS intensity due to the enlargement of molecular volume. The maximum scattering wavelength of RLS was at 290 nm. Moreover, under optimum conditions, the RLS intensity of the system increases linearly with the increase of thorium (IV) concentration in
