Characterizations of natural organic matter as nano particle using flow field-flow fractionation

Natural organic matter (NOM) was characterized, in terms of its size and diffusivity, using flow field-flow fractionation (FlFFF) equipped with both UV and fluorescence detections. FlFFF characterized a variety of NOM and provided their hydrodynamic effective sizes ranging 0.5–1.5 nm determined from the classical FlFFF theory, depending upon both NOM sources and carrier solutions of FlFFF. Diffusivities of various NOM, ranging approximately 4.0–7.0 × 10−6 cm2/s depending also upon NOM sources and carrier solutions, were also determined by FlFFF. Through FlFFF measurements with NOM, conversion equations from molecular weight unit (i.e., Dalton) to nanometer (nm) were suggested with varying ionic strength values.