  Optofluidic force induction (OF2i) is an optical nanoparticle characterization scheme which achieves real-time optical counting with single-particle sensitivity and high throughput. In a recent paper [\v{S}imi\'c et al., Phys. Rev. Appl. 18, 024056 (2022)], we have demonstrated the working principle for standardized polystrene nanoparticles, and have developed a theoretical model to analyze the experimental data. In this paper we give a detailed account of the model ingredients including the full working equations, provide additional justification for the assumptions underlying OF2i, and discuss directions for further developments and future research. 
Theoretical description of optofluidic force induction