The objective of this study was to evaluate the influence of solid lipid nanoparticles (SLN) loaded with the poorly water-soluble drug tamoxifen citrate (TC) on the in vitro antitumor activity and bioavailability of the drug. TC-loaded SLN were prepared by solvent injection method using glycerol monostearate (GMS) or stearic acid (SA) as lipid matrix. Poloxamer 188 or tween 80 were used as stabilizers. TC-loaded SLN (F3 and F4) prepared using GMS and stabilized by poloxamer 188 showed highest entrapment efficiency % (86.07 ± 1.74 and 90.40 ± 1.22%) and reasonable mean particle sizes (130.40 ± 9.45 and 243.80 ± 12.33 nm), respectively. The in vitro release of TC from F3 and F4 exhibited an initial burst effect followed by a sustained drug release. In vitro cytotoxicity of F3 against human breast cancer cell line MCF-7 showed comparable antitumor activity to free drug. Moreover, the results of bioavailability evaluation of TC-loaded SLN in rats compared to free TC indicated that 160.61% increase in the oral bioavailability of TC. The obtained results suggest that incorporation of the poorly water-soluble drug TC in SLN preserves the in vitro antitumor activity and significantly enhance oral bioavailability of TC in rats.

Purpose: The objective of this work was to formulate a delivery system of pDNA encoded p53 gene-loaded chitosan-sodium deoxycholate (CS-DS) nanoparticles, and to evaluate their influence on in vitro cytotoxicity and transfection efficiency of p53 gene. Methods: The prepared pDNA-loaded CS-DS nanoparticles were evaluated for morphology, particle size, zeta potential, entrapment efficiency %, in vitro release, in vitro cytotoxicity, and transfection efficiency. Results: The mean particle size ranged from from 96.5 ± 11.31 to 405 ± 46.39 nm. All nanoparticles had good positive zeta potential values. Entrapment efficiency % ranged from 38.25 ± 3.25 to 94.89 ± 5.67. The agarose gel electrophoresis confirmed the strong binding between plasmid and CS. The in vitro pDNA release from nanoparticles exhibited an initial burst effect followed by a sustained drug release over a period of 6 days. In vitro cytotoxicity against human Caco-2 cells showed low cell cytotoxicity of plain CS-DS nanoparticles, while pDNA-loaded CS-DS nanoparticles showed a cytotoxic effect with increasing nanoparticles' concentration. Gene transfection, analyzed by PCR and ELISA, showed a direct correlation between gene expression and concentration of pDNA. The highest expression of the gene was achieved with pDNA concentration of 9 µg/mL with 5.7 times increase compared to naked pDNA of the same concentration. Conclusion: The obtained results were very encouraging and offer an alternative approach to enhancing the transfection efficiency of genetic material-loaded chitosan-based delivery systems.

PurposeThis work aimed to synthesize surfactant-free AuNPs for targeted delivery of plasmid DNA encoded p53 gene and to avoid conventional production method of Gold nanoparticles (AuNPs) which may adversely affect the final shape, diversity, and size due to accumulation of the formulated surfactant – gold complex to the surface.MethodsThe AuNPs were fabricated using seeded-growth method with L-Cystine methyl ester hydrochloride as capping agent, then loaded with plasmid DNA encoded p53 gene. The resultant AuNPs and AuNPs-p53 complex were evaluated for physical characteristics and morphology. Confirmation of complex formation was performed using gel electrophoresis. Furthermore, the efficient delivery and cytotoxicity behavior of the encoded gene were examined on both healthy lung cells (WI38) and cancerous lung cells (A549).ResultsL-cysteine methyl ester hydrochloride AuNPs showed acceptable physical characteristics (30 nm, +36.9 mv, and spherical morphology). P53 attachment to AuNPs was confirmed by gel electrophoresis. The RT-PCR proved the overexpression of p53 by the fabricated AuNPs-p53 complex. The high percentage of cell viability in normal lung cell line (WI 38) proved the safety of L-cysteine methyl ester functionalized AuNPs. Additionally, the apoptotic effect due to expression of p53 gene loaded on AuNPs was only prominent in lung cancer cell line (A549), revealing selectivity and targeting efficiency of anticancer AuNPs-p53 complex.ConclusionAuNPs can be considered as a potential delivery system for effective transfection of plasmid DNA which can be used for successful treatment of cancer.