The effect of preparation conditions of chalcone based benzoxazine/magnetite nanocomposites on magnetization properties

In the current study, a hydroxylated chalcone (1-phenyl)-3-(4-hydroxyphenyl)prop-2-en-1-one, 4-aminobenzoic acid, and paraformaldehyde were combined in ethanol/toluene solvent to form a new benzoxazine monomer. 1H NMR and FTIR analysis were used to confirm the produced monomer. Polybenzoxazine was prepared by the thermal curing of chalcone-based benzoxazine monomer and examined using FTIR and XRD. Magnetite nanoparticles were prepared using two different solvents and mixed with benzoxazine monomer at various ratios, followed by insitu thermal curing to prepare polybenzoxazine/magnetite nanocomposites. These nanocomposites were analyzed by FTIR, XRD, DSC and TGA were used to examine the thermal characteristics of the resulted materials. The surface morphology was investigated using SEM, and the magnetic property was measured by VSM. The resulting benzoxazine monomer has a low curing temperature (160 °C). The addition of nanoparticles of magnetite to benzoxazine improved its thermal stability. Also, the inclusion procedure of magnetite into benzoxazine has a significant impact on its saturation magnetization.

Ultrasound-assisted preparation of different nanocarriers loaded with food bioactive ingredients

Developing green and facile approaches to produce nanostructures suitable for bioactives, nanoencapsulation faces some challenges in the nutraceutical and food bioactive industries due to potential risks arising from nanomaterials fabrication and consumption. High-intensity ultrasound is an effective technology to generate different bio-based structures in sub-micron or nanometer scale. This technique owing to some intrinsic advantages such as safety, straightforward operation, energy efficiency, and scale-up potential, as well as, ability to control over size and morpHology has stood out among various nanosynthetic routes. Ultrasonically-provided energy is mainly transferred to the droplets and particles via acoustic cavitation (which is formation, growth, and implosive collapse of bubbles in solvent). This review provides an outlook on the fundamentals of ultrasonication and some applicable setups in nanoencapsulation. Different kinds of nanostructures based on surfactants, lipids, proteins and carbohydrates formed by sonication, along with their advantages and disadvantages are assessed from the viewpoint of stability, particle size, and process impacts on some functionalities. The gastrointestinal fate and safety issues of ultrasonically prepared nanostructures are also discussed. Sonication, itself or in combination with other encapsulation approaches, alongside biopolymers generate nano-engineered carriers with enough stability, small particle sizes, and a low polydispersity. The nano-sized systems improve techno-functional activities of encapsulated bioactive agents including stability, solubility, dissolution, availability, controlled and targeted release profile in vitro and in vivo plus other bioactive properties such as antioxidant and antimicrobial capacities. Ultrasonically prepared nanocarriers show a great potential in fortifying food products with desired bioactive components, especially for the industrial applications.

PNIPAAm-MAA nanoparticles as delivery vehicles for curcumin against MCF-7 breast cancer cells

Breast cancer is the most frequently occurring cancer among women throughout the world. Natural compounds such as curcumin hold promise to treat a variety of cancers including breast cancer. However, curcumin's therapeutic application is limited, due to its rapid degradation and poor aqueous solubility. On the other hand, previous studies have stated that drug delivery using nanoparticles might improve the therapeutic response to anticancer drugs. Poly(N-isopropylacrylamide-co-methacrylic acid) (PNIPAAm-MAA) is one of the hydrogel copolymers utilized in the drug delivery system for cancer therapy. The aim of this study was to examine the cytotoxic potential of curcumin encapsulated within the NIPAAm-MAA nanoparticle, on the MCF-7 breast cancer cell line. In this work, polymeric nanoparticles were synthesized through the free radical mechanism, and curcumin was encapsulated into NIPAAm-MAA nanoparticles. Then, the cytotoxic effect of curcumin-loaded NIPAAm-MAA on the MCF-7 breast cancer cell line was measured by MTT assays. The evaluation of the results showed that curcumin-loaded NIPAAm-MAA has more cytotoxic effect on the MCF-7 cell line and efficiently inhibited the growth of the breast cancer cell population, compared with free curcumin. In conclusion, this study indicates that curcumin-loaded NIPAAm-MAA suppresses the growth of the MCF-7 cell line. Overall, it is concluded that encapsulating curcumin into the NIPAAm-MAA copolymer could open up new avenues for breast cancer treatment.

Cisplatin release from dual-responsive magnetic nanocomposites

BACKGROUND

The combination of hyperthermia and controlled drug delivery is a very promising recent effort in cancer therapy. The aim of this study is to synthesize and characterize a dual pH/thermal-responsive composite nanoparticle that acts as a cisplatin carrier, and to evaluate its release profile at different pH and temperature conditions relevant to the physiological and cancerous environment during hyperthermia.

METHODS

Poly (n-isopropyl acrylamide-methacrylic acid-hydroxy ethyl methacrylate) (P (NIPAAM-MAA-HEM)) was synthesized by emulsion polymerization. Fe3O4 magnetic nanoparticles (MNPs) and cisplatin were loaded onto the nanogel, by the swelling method and the conjugation of cisplatin with the -COOH group of MAA, respectively. The chemical and morphological properties of the drug-loaded composite nanoparticle and its profile of drug release at pH levels of 7.4 (physiological pH), 6.8 (tumor extracellular pH), and 5.3 (endosomal pH), and at temperatures of 37°C (physiological) and 43°C (hyperthermia), were studied.

RESULTS

The result shows that the synthesized nanogel and nanocomposite were almost pure and were of an appropriate size and stability. Magnetic saturation was at a position appropriate for the production of enough heat during hyperthermia. A high level of drug release under conditions of low pH and high temperature was observed.

CONCLUSION

This result suggests that the dual pH/temperature-responsive P (NIPAAM-MAA-HEM) magnetic nanocomposite can be very effective in hyperthermia and controlled cisplatin delivery.

Comparison, synthesis and evaluation of anticancer drug-loaded polymeric nanoparticles on breast cancer cell lines

Breast cancer is a major form of cancer, with a high mortality rate in women. It is crucial to achieve more efficient and safe anticancer drugs. Recent developments in medical nanotechnology have resulted in novel advances in cancer drug delivery. Cisplatin, doxorubicin, and 5-fluorouracil are three important anti-cancer drugs which have poor water-solubility. In this study, we used cisplatin, doxorubicin, and 5-fluorouracil-loaded polycaprolactone-polyethylene glycol (PCL-PEG) nanoparticles to improve the stability and solubility of molecules in drug delivery systems. The nanoparticles were prepared by a double emulsion method and characterized with Fourier Transform Infrared (FTIR) spectroscopy and Hydrogen-1 nuclear magnetic resonance ((1)HNMR). Cells were treated with equal concentrations of cisplatin, doxorubicin and 5-fluorouracil-loaded PCL-PEG nanoparticles, and free cisplatin, doxorubicin and 5-fluorouracil. The 3-[4,5-dimethylthiazol-2yl]-2,5-diphenyl tetrazolium bromide (MTT) assay confirmed that cisplatin, doxorubicin, and 5-fluorouracil-loaded PCL-PEG nanoparticles enhanced cytotoxicity and drug delivery in T47D and MCF7 breast cancer cells. However, the IC50 value of doxorubicin was lower than the IC50 values of both cisplatin and 5-fluorouracil, where the difference was statistically considered significant (p˂0.05). However, the IC50 value of all drugs on T47D were lower than those on MCF7.

Magnetic nanoparticles as potential candidates for biomedical and biological applications

Magnetic iron oxide nanoparticles have become the main candidates for biomedical and biological applications, and the application of small iron oxide nanoparticles in in vitro diagnostics has been practiced for about half a century. Magnetic nanoparticles (MNPs), in combination with an external magnetic field and/or magnetizable grafts, allow the delivery of particles to the chosen target area, fix them at the local site while the medication is released, and act locally. In this review, we focus mostly on the potential use of MNPs for biomedical and biotechnological applications, and the improvements made in using these nanoparticles (NPs) in biological applications.

Curcumin inhibits leptin gene expression and secretion in breast cancer cells by estrogen receptors

Background

Recent studies suggested that leptin as a mitogenic factor might play an important role in the process of initiation and progression of human cancer. Therefore, it could be considered as a target for breast cancer therapy. A previous study has showed that expression of leptin gene could be modulated by activation of estrogen receptors. Curcumin is a diferuloylmethane that has been shown to interfere with multiple cell signaling pathways and extensive research over the last 50 years has indicated this polyphenol can both prevent and treat cancer. Based on the fact that targeting of leptin could be considered as a novel strategy for breast cancer therapy, the aim of this study is the investigation of potentiality of curcumin for inhibition of leptin gene expression and secretion, and also, its link with expression of estrogen receptors.

Methods

Cytotoxic effect of curcumin on T47D breast cancer cells was investigated by MTT assay test after 24 and 48 treatments. Thereafter, the cells treated with different concentrations of curcumin. The levels of leptin, estrogen receptor α and estrogen receptor β genes expression was measured in the treated and control cells by Reverse-transcription real-time PCR. Amount of secreted leptin in the culture medium was also determined by ELISA in both treated and untreated cells. Finally data were statistically analyzed by one-way ANOVA test.

Results

Analysis of MTT assay data showed that curcumin inhibits growth of T47D cells with dose dependent manner. There were also significant difference between control and treated cells in the levels of leptin, estrogen receptor α expression levels and the quantity of secreted leptin that both were decreased in the treated cells compared with control cells.

Conclusion

Based on the results, curcumin inhibits the expression and secretion of leptin and it could probably be used as a drug candidate for the breast cancer therapy through the leptin targeting in the future.

Dendrimers: synthesis, applications, and properties

Dendrimers are nano-sized, radially symmetric molecules with well-defined, homogeneous, and monodisperse structure that has a typically symmetric core, an inner shell, and an outer shell. Their three traditional macromolecular architectural classes are broadly recognized to generate rather polydisperse products of different molecular weights. A variety of dendrimers exist, and each has biological properties such as polyvalency, self-assembling, electrostatic interactions, chemical stability, low cytotoxicity, and solubility. These varied characteristics make dendrimers a good choice in the medical field, and this review covers their diverse applications.