Correlation and Autocorrelation Analysis of Nanoscale Rotational Dynamics

Single particle orientation and rotational tracking (SPORT) has been proven to be a highly effective upgrade to the conventional single particle tracking (SPT) techniques for investigating nanoscale rotational dynamics in chemical and biological systems. Data analysis in SPORT is particularly important to extract useful information from the dynamic behaviors of individual anisotropic probes with sufficiently high accuracy, revealing the underlying working mechanisms. In this study, using polyethylene glycol (PEG)-modified gold nanorods (AuNRs) on synthetic lipid bilayers as a model system, we performed the correlation and autocorrelation analyses coupled with computer simulation and investigated the reliable conditions for extracting the rotational mode and speed. Time series binning was used to study the influence of exposure time on the accuracy of correlation and autocorrelation analyses. This systematic study on data treatment will be beneficial to future SPORT data interpretations and experimental designs.