Quantifying miR-150 Nanoparticle Encapsulation

The amount of miR-150-loaded in nanoparticles was determined as described previously.22 (link) In brief, the amount of un-entrapped miR-150 mimics in the nanoparticle wash solutions obtained during the formulation step was quantified using the Quant-iT™ PicoGreen Assay kit (Thermo Fisher Scientific, Waltham, MA, USA). Fluorescence resulting from the binding of PicoGreen reagent to miR-150 was measured in a black-bottomed 96-well plate using FLx-800 microplate reader (BIO-TEK Instruments, Winooski, VT, USA). miR-150 loading in nanoparticles was determined by subtracting the total amount of miR-150 recovered in the wash solutions (miR-150_w) from the initial amount of miR-150 (miR-150_i) added. Encapsulation efficiency was calculated as:
$(\text{miR-}{150}_{\mathrm{i}}-\text{miR-}{150}_{\mathrm{w}}/\text{miR-}{150}_{\mathrm{i}})\times 100$