Optical forces can be used to manipulate and trap arrays of aerosol particles in order to study their dynamics. We demonstrate the use of a novel technique for the controlled loading of multiple gradient force optical traps and show how this technique may provide an aerosol analogue to microfluidics. We go on to present the use of this technique to study the processes that govern Brownian coagulation of aerosol particles, one of the most fundamental processes governing aerosol size distribution a key parameter for characterising the role of aerosols in atmospheric science.
