Nanoparticle characterization in nanoliter volumes by grating light reflection spectroscopy

We present both theoretical and experimental results demonstrating that grating light reflection spectroscopy (GLRS) can provide information about the concentration and average size of particles of nanometer dimensions distributed in liquid-phase media. To demonstrate this, we have performed experiments on various concentrations of dendrimeric oligomers in water. Our results show that, with GLRS, we can determine the mean radius of particles with sizes on the order of molecular dimensions. The measurements were carried out in a continuous-flow format using a microchannel flow system and in a detection volume of less than 200 nL