Hydrodynamic chromatography is similar to size exclusion chromatography, except, due to the non-porous nature of the stationary phase; there are fewer possibilities of solid phase interactions. Our HDC is coupled to diode array, fluorescence, refractive index and multiple angle light scattering (MALS) detectors. The 18 angle MALS detector is ideal for the measurement of absolute molar mass, size and conformation for particles or polymeric materials. This detector avoids many of the problems associated with DLS by first separating the sample into characteristic size classes.