Synthesis of quasi-spherical and square shaped oligoamino-ester graft-from magnetite nanoparticles: Effect of morphology and chemical structure on protein interactions

Hydroxyapatite Incorporated with Fe3O4@MCM-41 Core-Shell: A Promising Nanocomposite for Teriparatide Delivery in Bone Tissue Regeneration

This article presents a comprehensive study of the development of a novel nanocomposite comprising core-shell Fe3O4@MCM-41 with superparamagnetic properties and hydroxyapatite (HAp). The nanocomposite serves as a pH-responsive nanocarrier, offering an efficient injectable dosage for teriparatide (PTH (1-34)) delivery. The aim is to address the limitations associated with drug-induced side effects, precautionary measures, and frequent injections. The nanocomposites, as prepared, were characterized using techniques including X-ray diffraction, Fourier transform infrared, zeta potential, dynamic light scattering, VSM, scanning electron microscopy, and transmission electron microscopy. The nanocomposites' average crystallite diameter was determined to be 27 ± 5 nm. The hydrodynamic size of the PTH (1-34)-loaded nanocarrier ranged from 357 to 495 nm, with a surface charge of -33 mV. The entrapment and loading efficiencies were determined to be 73% and 31%, respectively. All of these findings collectively affirm successful fabrication. Additionally, in vivo medication delivery was investigated using the HPLC method, mirroring the in vitro tests. Utilizing the dialysis approach, we demonstrated sustained-release behavior. PTH (1-34) diffusion increased as the pH decreased from 7.4 to 5.6. After 24 h, drug release was higher at acidic pH (88%) compared to normal pH (43%). The biocompatibility of the PTH (1-34)-loaded nanocarrier was assessed using the MTT assay employing the NIH3T3 and HEK-293 cell lines. The results demonstrated that the nanocarrier not only exhibited nontoxicity but also promoted cell proliferation and differentiation. In the in vivo test, the drug concentration reached 505 μg within 30 min of exposure to the magnetic field. Based on these findings, the Fe3O4@MCM-41/HAp/PTH (1-34) nanocomposite, in combination with a magnetic field, offers an efficient and biocompatible approach to enhance the therapeutic effect of osteogenesis and overcome drug limitations.

Ultrasound-assisted synthesis of pH-responsive nanovector based on PEG/chitosan coated magnetite nanoparticles for 5-FU delivery

pH-responsive magnetic carriers at the nanoscale are one of the most important agents for the targeted treatment of cancer. In this study, Fe₃O₄ nanoparticles were prepared by co-precipitation method and functionalized with three types of PEG using ultrasound waves. PEGlated particles were modified with chitosan shell through ultrasound-assisted double emulsion method. The prepared material which was used as a pH responsive carrier for pinpointed 5-FU delivery. The chemico-physical properties of prepared nanoparticles have been investigated. Results demonstrated that pure Fe₃O₄ had a mean diameter of 20nm with the regular spherical shape which was increased after modification step depending on the type of PEG. 5-FU loading properties and releasing behaviors studies in different pHs which showed that 5-FU can be efficiently loaded in the Fe₃O₄@Cs-PEG. Also, in the case of release, the amount of 5-FU released at pH=5.8 is noticeably higher compared to the released amount at pH=7.4 in all three samples at any distinct time. For instance at pH=7.4, 27% of the 5-FU was released from the Fe₃O₄@Cs-PEG2 during 48h; as the pH decreases to 5.8, the cumulative amount of 5-FU released enhanced to 52%. The in vitro MTT assay results demonstrated that the cell viability decreases in all synthesized nanoparticles as the pH medium of MCF-7 culture became to 5.8. For example, cell viability of Fe₃O₄@Cs-sPEG decreased from 44±2% to 36±1.9% at a concentration of 5 (μg/ml) as the pH varied from 7.4 to 5.8.

Design and synthesis of pH-sensitive polyamino-ester magneto-dendrimers: Surface functional groups effect on viability of human prostate carcinoma cell lines DU145

Novel pH-sensitive, biocompatible and biodegradable magneto-dendrimers with OH and/or NH2 functional groups based on poly amino-ester were synthesized for delivery of anti-cancer drugs. Magnetite nanoparticles (MNPs) were synthesized by the co-precipitation method and their surfaces were modified by 3-aminopropyl triethoxysilane. The first and second generations of the magneto-dendrimer with hydroxyl end groups were produced by sequential acrylation and Michael addition reactions using the required amounts of acryloyl chloride and diethanolamine, respectively. The dendrimer containing amino functional surface groups up to second generation was synthesized by the same method using the necessary amounts of acryloyl chloride and ethylenediamine. These dendrimers were fully characterized by the Fourier transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), dynamic light scattering (DLS) and zeta potential analysis, vibrating-sample magnetometer (VSM), scanning electron microscope (SEM), transmission electron microscopy (TEM) and selected area electron diffraction (SAED). In-vitro release profiles of the drug-loaded magnetic nanoparticles and their cytotoxicity assay were investigated at two pHs (7.4 and 5.8). The hydrolytic degradation behavior of magneto-dendrimers was evaluated in PBS buffer. Our research suggests that magneto-dendrimers having amine or hydroxyl functional groups could be considered as the suitable nanocarriers for therapy applications.