Polyamidoamine (PAMAM) dendrimers are extensively researched as potential drug delivery system thanks to their desirable features such as controlled and stable structures, and ease of functionalization onto their surface active groups. However, there have been concerns about the toxicity of full generation dendrimers and risks of premature clearance from circulation, along with other physical drawbacks presented in previous formulations, including large particle sizes and low drug loading efficiency. In our study, carboxyl-terminated PAMAM dendrimer G3.5 was grafted with poly (ethylene glycol) methyl ether (mPEG) to be employed as a nano-based drug delivery system with great cytocompatibility for the delivery of carboplatin (CPT), a widely prescribed anticancer drug with strong side effects so that the drug will be effectively entrapped and not exhibit uncontrolled outflow from the open structure of unmodified PAMAM G3.5. The particles formed were spherical in shape and had the optimal size range (around 36 nm) that accommodates high drug entrapment efficiency. Surface charge was also determined to be almost neutral and the system was cytocompatible. In vitro release patterns over 24 h showed a prolonged CPT release compared to free drug, which correlated to the cytotoxicity assay on malignant cell lines showing the lack of anticancer effect of CPT/mPEG-G3.5 compared with CPT.

In this study, the introduction of Origanum majorana L. essential oil into a polyamidoamine (PAMAM) G4.0 dendrimer was performed for creation of a potential nanocide against Phytophthora infestans. The characteristics of marjoram oil and PAMAM G4.0 was analyzed using transmission electron spectroscopy (TEM), nuclear magnetic resonance spectroscopy (¹H-NMR) and gas chromatography mass spectrometry (GC-MS). The success of combining marjoram oil with PAMAM G4.0 was evaluated by FT-IR, TGA analysis, and the antifungal activity of this system was also investigated. The results showed that the antifungal activity of oil/PAMAM G4.0 was high and significantly higher than only PAMAM G4.0 or marjoram essential oil. These results indicated that the nanocide oil/PAMAM G4.0 helped strengthen and prolong the antifungal properties of the oil.

In the present work, a dual-drug-loaded soy lecithin liposomal system was developed by coencapsulation of Letrozole (LET) with Paclitaxel (PTX) to improve the efficacy in breast cancer therapy. Liposomes were synthesized by the thin film layer hydration. To sufficiently evaluate the characteristics of these liposomes, the particle size, zeta potential, morphology, drug encapsulation, in vitro drug release, and cytotoxicity were ascertained. Results showed promisingly anticancer potentials, as the following parameters indicated: nanosize diameter (around 193nm) and negative surface charge. Data collected from the coloaded drug liposomes showed suitable encapsulation efficiency (50.56 for PTX and 31.13 for LET). Controlled and sustained releases were achieved up to 72h for both the loaded drugs following the diffusion mechanism. In addition, the in vitro cytotoxicity study on the human breast cancer cell line (MCF-7) given the dual-drug-loaded liposome showed greater inhibition of cell growth than the single drug. Consequently, LET and PTX coloaded liposomes made from soy lecithin are expected to be an ingenious drug-delivery system for combination chemotherapy.