2.3.2. Poly(I:C)-Release from µRs

A release study was performed in a salt mixture resembling a phagolysosome’s physiological condition following Stefaniak et al. [28] as described previously [15]. In brief, µRs were incubated in 0.5 mL salt solution at 37 °C under shaking conditions for the indicated period. The solution was centrifuged at 20,000× g for 15 min, supernatant was mixed with SYBR^® Gold (S11494, Invitrogen, Waltham, MA, USA), and the fluorescence measured at 485 nm.