Encapsulation of essential oils in chitosan nanoparticle formulations and Investigation on their antioxidant and antibacterial properties.

Peppermint oil (PO) and Green Tea oil (GTO) are two essential oils (EOs) were encapsulated in chitosan nanoparticles (CS NPs) via two-steps method (emulsification followed by ionic gelation). Encapsulation of GTO and PO in CS NPs were investigated through different characterization techniques such as; Fourier transform infrared (FT-IR) spectroscopy, powder X-ray diffraction (XRD). Both NPs (CS/PO NPs and CS/GTO NPs) showed a spherical shape with 20-90 nm size range as detected by Transmission electron microscopy (TEM). Thermogravimetric analysis (TGA) was used to study the thermal stability of both bulk and encapsulated EOs that showed an enhancement in the thermal stability of both encapsulated EOs by about 2.18 and 1.75 folds for PO and GTO, respectively. Through UV-vis spectroscopy, both encapsulation efficiency (EE%), loading capacity (LC%) and in-vitro release were estimated. EE% of CS/PO NPs and CS/GTO NPs were about 82-78% and 22-81%, respectively, when the initial EO amount was 0.25–1 w/w CS. Whereas, the loading capacity (LC%) of CS/PO NPs and CS/GTO NPs were about 8-22% and 2.2-23%, respectively for the initial EO amount was 0.25–1 w/w CS. The in-vitro release studies of both EOs showed an initial rapid release profile followed by a slow release at two different pH conditions: acidic pH (acetate buffer) and neutral pH (phosphate buffer saline). Furthermore, the stability of the total phenolic contents (TPC) of both EOs in CS NPs was studied using Folin–Ciocalteu reagent. The antioxidant activity of both pure and encapsulated PO and GTO was evaluated by 2,2-diphenyl-1-picrylhydrazyl radical (DPPH). The antioxidant activities of CS/PO NPs and CS/GTO NPs were improved by about 2 and 2.4 folds, respectively. Finally, agar dilution and colony counting method were used to study the antibacterial activity of pure and encapsulated PO and GTO against Gram positive (Staphylococcus aureus) and Gram negative (Escherichia coli) bacteria. In case of Gram positive bacteria, encapsulated PO showed an enhanced antibacterial activity by about 39.63%, while encapsulated GTO showed an improvement in antibacterial activity by about 57.5% on the other hand, against Gram negative bacteria, encapsulated PO showed an enhanced antibacterial activity by about 3%, while encapsulated GTO showed an improvement in antibacterial activity by about 1.8%

Green tea essential oil encapsulated chitosan nanoparticles-based radiopharmaceutical as a new trend for solid tumor theranosis

The existing study is embarked on investigating the antineoplastic activity of green tea essential oil (GTO) as a natural product. In this regard, GTO was encapsulated in cationic chitosan, nitrogenous-polysaccharide derived by partial deacetylation of chitin, nanoparticles (CS NPs) with entrapment efficiency (EE%) of 81.4 ± 5.7% and a mean particle-size of 30.7 ± 1.13 nm. Moreover, the cytotoxic effect of CS/GTO NPs was evaluated versus human liver (HepG-2), breast (MCF-7) and colon (HCT-116) cancer cell-lines and exhibited a positive impact when compared to bare CS NPs by 3, 2.3 and 1.7 fold for the three cell lines, respectively. More interestingly, CS/GTO NPs were complexed with technethium-99m (Tc) radionuclide. With a view to achieve a successful radiolabeling process, different parameters were optimized resulting in a radiolabeling efficiency (RE%) of 93.4 ± 1.2%. Radiopharmacokinetics of the radiolabeled NPs in healthy mice demonstrated a reticuloendothelial system (RES) evading and long blood circulation time up to 4 h. On the other hand, the biodistribution profile in solid tumor models showed 20.3 ± 2.1% localization and cancer cell targeting within just 30 min. On the whole, the reported results encourage the potential use of CS/GTO NPs as a side effect-free anticancer agent and its Tc-analogue as a novel CS/GTO NPs-based diagnostic-radiopharmaceutical for cancer

Comparative study of encapsulated peppermint and green tea essential oils in chitosan nanoparticles: Encapsulation, thermal stability, in-vitro release, antioxidant and antibacterial activities

Essential oils (EOs) such as Peppermint oil (PO) and Green Tea oil (GTO) have extensively been reported for their nutritional and biomedical properties. To overcome the sensitivity of EOs to the environmental conditions, nano-encapsulation has emerged as a method to address this limitation. In this work, PO and GTO were encapsulated in chitosan nanoparticles (CS NPs) following emulsification/ionic gelation method. The nano-encapsulated PO (CS/PO NPs) and GTO (CS/GTO NPs) were fully characterized by various methods. Spherical NPs with an average size range of 20–60 nm were revealed by TEM for both systems. The loading capacity reached 22.2% and 23.1%, for PO and GTO, respectively, and the in-vitro release followed a Fickian behavior in different buffer systems. The TGA thermograms of both nano-encapsulated EOs showed an increase in the temperature of maximum degradation rate up to 350 °C. The nano-encapsulation maintained the stability of the total phenolic contents in both EOs, improved the antioxidant activity by ~2 and 2.4-fold for PO and GTO respectively. Surprisingly, the antibacterial activity of CS/GTO NPs was more potent than CS/PO NPs and especially against Staphylococcus aureus with ~9.4 folds improvement compared to pure GTO, and ~4.7 fold against Escherichia coli

The potential of carbon-based nanomaterials in hepatitis C virus treatment: a review of carbon nanotubes, dendrimers and fullerenes

Abstract HCV, hepatitis C virus, is a virus that causes damage to the liver. Both chronic infection or lack of treatment increase morbidity except if it is an acute infection, as the body clears the virus without any intervention. Also, the virus has many genotypes, and until now, there has yet to be a single treatment capable of affecting and treating all these genotypes at once. This review will discuss the main and most used old treatments, IFN-a, PEG IFN-a, Ribavirin, Celgosvir, and sofosbuvir alone and with the combination of other drugs and their drawbacks. They should be given in combination to improve the effect on the virus compared with being administrated independently, as in the case of sofosbuvir. For these reasons, the need for new treatments and diagnostic tools arises, and the rule of nanotechnology comes here. The role of carbon nanotubes, dendrimers, and fullerenes will be discussed. CNTs, carbon nanotubes, are one-dimensional structures composed of a cylindrical sheet of graphite and are mainly used for diagnostic purposes against HCV. Dendrimers, three-dimensional highly branched structures, are macromolecules that provide better drug delivery and treatment options due to their unique structure that can be modified, producing versatile types; each has unique properties. Fullerenes which are cage like structures derived and closely related to CNTs, and composed of carbon atoms that can be substituted by other atoms which in return open unlimited usage for these carbon based materials. Fullerenes rule is unique since it has two mechanisms that prevent the virus from binding and acting on the virus-replicating enzyme. However, their charge needs to be determined; otherwise, it will lead to cytotoxicity. Lastly, no review has been done on the role of nanotechnology against HCV yet

Applying Box–Behnken Design for Formulation and Optimization of PLGA-Coffee Nanoparticles and Detecting Enhanced Antioxidant and Anticancer Activities

In an attempt to prove biological activity enhancement upon particle size reduction to the nanoscale, coffee (Cf) was chosen to be formulated into poly(lactic-co-glycolic) acid (PLGA) nanoparticles (NPs) using the single emulsion-solvent evaporation (SE-SE) method via Box–Behnken Design (BBD) to study the impact of certain process and formulation parameters on the particle size and size homogeneity, surface stability and encapsulation efficiency (EE%). The coffee-loaded PLGA (PLGA-Cf) NPs were characterized by different methods to aid in selecting the optimum formulation conditions. The desirable physicochemical characteristics involved small particle sizes with an average of 318.60 ± 5.65 nm, uniformly distributed within a narrow range (PDI of 0.074 ± 0.015), with considerable stability (Zeta Potential of −20.50 ± 0.52 mV) and the highest EE% (85.92 ± 4.01%). The antioxidant and anticancer activities of plain PLGA NPs, pure Cf and the optimum PLGA-Cf NPs, were evaluated using 2,2-Diphenyl-1-picryl-hydrazyl (DPPH) and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays, respectively. As a result of nano-encapsulation, antioxidant activity was enhanced by 26.5%. Encapsulated Cf showed higher anticancer potency than pure Cf against different cancerous cell lines with an increase of 86.78%, 78.17%, 85.84% and 84.84% against MCF-7, A-549, HeLa and HepG-2, respectively. The in vitro release followed the Weibull release model with slow and biphasic release profile in both tested pH media, 7.4 and 5.5