Shape separation of nanometer cold particles by size-exclusion chromotography

The shape separations of suspended gold nanoparticles were investigated usi ng size-exclusion chromatography. The separations in shapes were identified by examining the 3-D chromatograms obtained by employing a diode; away det ection system and were further confirmed by analyzing TEM images of fractio nal collection of particles; This shape separation was achieved by adding a mixed-surfactant system containing sodium dodecyl sulfate and poluoxyethyl ene (23) dodecanol (Brij-35) into the eluent; which apparently affects the adsorption behaviors of both rodlike and spherical Au nanoparticles onto th e column packing materials. While the overall particle gross sizes of these two shapes were similar, the baseline resolution was unfortunately not obt ainable. However, the absorption spectra from the diode-array detector coul d be utilized td interpret the shapes of Au nanoparticles. The potential ca pability for the size separation of Au nanoparticles by size-exclusion chro matography with diode-away detection was also demonstrated.