Dendrimers have been attracting growing attention because of their unique well-defined globular nanoscale architecture and numerous functional groups on the surface. Attachment of PEG to the dendrimer generates stealth dendrimers, which have promising structural advantages for drug delivery. In this study, synthetic methods were explored to deliver antiarrhythmic quinidine by stealth dendrimers. In particular, quinidine was covalently attached to anionic G2.5 and cationic G3.0 polyamidoamine (PAMAM) dendrimers via a glycine spacer, respectively. The resulting quinidine-PAMAM-PEG conjugates were characterized and confirmed by FT-IR and 1H-NMR. In vitro hydrolysis was carried out in pH 7.4 PBS buffer at 37°C to confirm the bioavailability of the conjugated quinidine.