A NIR Aggregation-Induced Emission Fluoroamphiphile as Visually Trackable and Serum-Tolerant Nonviral Gene Carrier

Functional fluorescence (FL) nonviral gene vectors with high serum tolerance bear broad application prospects in gene delivery. Fluorination has been widely utilized as an effective strategy to enhance serum tolerance. Herein, we show the combination of fluorination and aggregation-induced emission (AIE) for the construction of a nonviral gene vector with low cytotoxicity, visual tracking ability, and high serum tolerance. Large π-conjugation triphenylamine (TPA) derivative with a characteristic D-π-A structure was modified with two polar [12]aneN₃ heads and a long fluorocarbon tail, giving the vector molecule FluoTPA. FluoTPA features near-infrared (NIR) emission, large Stokes shift, and strong binding affinity toward nucleic acids. Liposomes consisting of FluoTPA and dioleoylphosphatidylethanolamine (DOPE) (FluoTPA/DOPE) can effectively deliver both plasmid DNAs (pDNAs) and siRNAs into cells. Impressively, FluoTPA/DOPE showed comparable transfection efficiency (TE) in the presence of serum content up to 30% with that in the serum-free condition and achieved 7.4 times higher TE than the commercial transfection agent lipofectamine 2000 at the same condition. Finally, spatiotemporal tracking of the delivery process in cells was demonstrated. The results in this work suggest that FluoTPA could be a reliable theranostic platform for the nonviral delivery of nucleic acid therapeutics in serum condition.