Experimental setup and electrically modulated drug release from the nanofluidic platform

Figure 4. Experimental setup and electrically modulated drug release from the nanofluidic platform. (A) Schematic of the custom-built in vitro drug delivery platform, featuring a horizontally oriented dual-reservoir cuvette with the nanofluidic membrane clamped between a drug reservoir and a sink reservoir. Continuous magnetic stirring in the sink ensures homogeneous distribution of the released compound, which is quantified in real-time via UV-Vis spectroscopy. (B) Summary table of the key physicochemical characteristics of the tested drug models, including molecular weight, net charge, and hydrophilicity. (C-E) In vitro cumulative release profiles of three representative drug models through the nanofluidic membrane under modulated electrical stimulation: (C) Vitamin B12, a medium size, positively charged molecule; (D) Cabotegravir, a small, neutrally charged antiretroviral drug; and (E) Polystyrene sulfonate, a high molecular weight, highly negatively charged polymer. (F) Statistical comparison of release modulation efficiency across the different drug models, demonstrating consistent performance of the nanofluidic platform irrespective of molecular size or charge.