Docetaxel (DTX) and betulinic acid (BA) co-encapsulated poly-lactic co-glycolic acid (PLGA) nanoparticles (NPs) were developed for enhanced lung cancer activity in vitro. Poly (lactic-co-glycolic acid) (PLGA) was used as an encapsulating polymer along with polyvinyl alcohol (PVA) as a stabilizing base to formulate NPs with the double-emulsion solvent evaporation method to study the size and potential, along with the surface morphology and in vitro release, of NPs. Cell culture studies like in vitro cellular uptake, apoptosis, and cell cycle arrest were performed in an in vitro cytotoxicity study to access the NP’s effect in the A549 human lung cancer cell line. The emulsification solvent evaporation technique produced smooth spherical nanoparticles of small sizes with a relatively narrow size distribution (147.2 ± 12.29 nm). On the A549 cell line, the formulation showed higher cytotoxicity (6.43 ± 0.11, 4.21 ± 0.32, and 1.17 ± 0.23 µmol for 24, 48, and 72 h, respectively) compared to the free drug due to an increase in vitro cellular uptake. Apoptosis and cell cycle analysis also confirmed the effectiveness of the prepared NPs. In vitro studies have proven the tumor-targeting potential of DTX-BA-NPs in A549 cell lines and could be future medication for lung cancer treatment.

Despite various efforts, a successful selective delivery system for chemotherapeutic agents for lung cancer is still lacking. Dry powder inhaler (DPI) systems based on proliposomes (PLMs) could be a potential system for the efficient delivery of paclitaxel to lungs. PLM-based DPI prepared with a freeze-drying method can therefore be an alternative. Paclitaxel-loaded PLM-based DPI (PTX-PLM-DPI) powders were prepared using the method of thin film deposition on a carrier followed by freeze drying. These were prepared using soya phosphatidylcholine (SPC) and cholesterol as the lipids and mannitol as the carrier. The reconstituted liposomes were evaluated in terms of size, morphology, drug entrapment, release and cytotoxicity. The DPI powders were evaluated for their flow property, surface topography, dose uniformity and in vitro lung deposition. Stable and free-flowing PTX-PLM-DPI powder was obtained that could be reconstituted into homogenous liposomal vesicles < 200 nm as confirmed by TEM and SEM studies. The liposomes showed drug entrapment of 92.64 ± 1.4% and diffusion-controlled release of up to 28% in 24 h. These liposomes showed better dose-dependent cytotoxicity in A549 cells in comparison to paclitaxel suspension with IC₅₀ values of 46 ± 0.87 ng/mL and 154.9 ± 3.64 ng/mL, respectively. In vitro lung deposition studies of the PTX-PLM-DPI showed sufficient deposition with the fine particle fraction (FPF) of 50.86 ± 2.8% of particles with an aerodynamic diameter less than 5 µ. Hence, it canbe concluded that PLM-based DPI prepared by freeze drying can be a promising, stable, safe and free-flowing system for the enhanced lung delivery of paclitaxel.