document: Several approaches have been developed to quantify a number of fluorophores, such as fluorescence fluctuation spectroscopy for moving complexes27 or localization fluorescence imaging systems, including photoactivated localization microscopy/stochastic optical reconstruction microscopy28 and single-molecule photobleaching (SMPB) imaging.29 To quantify the b-3WJ RNA molecules within individual Qβ VLPs, the SMPB system was adapted here. Individual b-3WJsiSCR MG were immobilized on polyethylene