  Nanoparticle Tracking Analysis (NTA) provides a simple method to determine
individual nanoparticle size. However, because size quantification is based on
the slowly converging statistical law of random event, its intrinsic error is
large, especially in case of limited event number, e.g. for weak scattering
nanoparticles. Here, we introduce an NTA improvement by analyzing each
individual NP trajectory while taking into account the other trajectories with
a weighting coefficient. This weighting coefficient is directly derived from
the optical signature of each particle measured by quantitative phase
microscopy. The simulations and experimental results demonstrate the
improvement of NTA accuracy, not only for mono-disperse but also for
poly-disperse particle solutions.
