Figure 2.

Validation of the cellular internalization by TMR‐NAD⁺ 1. A) HeLa cells were incubated with TMR‐NAD⁺ 1, DOTAP transfection mixture and analyzed by confocal microscopy. Controls were performed without the transfection reagent DOTAP. (Scale bar: 20 μm). B) Plot showing the cell viability of HeLa cells in the presence of the developed transfection method using TMR‐NAD⁺ 1. HeLa cells (5000 cells per well) were seeded in a 96‐well plate and the transfection method was used to transfect TMR‐NAD⁺ 1. The cell viabilities in the presence of mod. NAD⁺ are reported relative to cell viability of HeLa cells without treatment as a control. C) Transfection efficiency of TMR‐NAD⁺ 1 determined by flow cytometry compared to cells without the transfection reagent DOTAP. Cells treated with the developed transfection method showed an over 10‐fold increased uptake of TMR‐NAD⁺ 1.