Thermoresponsive polymer gated and superparamagnetic nanoparticle embedded hollow mesoporous silica nanoparticles as smart multifunctional nanocarrier for targeted and controlled delivery of doxorubicin.

The design and development of drug-delivery nanocarriers with high loading capacity, excellent biocompatibility, targeting ability and controllability have been the ultimate goal of the biomedical research community. In this work, we have reported the synthesis and characterization of novel and smart thermoresponsive polymer coated and Fe3O4 embedded hollow mesoporous silica (HmSiO2) based multifunctional superparamagnetic nanocarriers for the delivery of doxorubicin (Dox) for cancer treatment. P(NIPAM-MAm) coated and Fe3O4 nanoparticle (NP) embedded hollow mesoporous silica nanocomposite (HmSiO2-F-P(NIPAM-MAm)) was prepared by the in situ polymerization of NIPAM and MAm monomers on the surface of hollow mesoporous silica NPs (HmSiO2) in the presence of Fe3O4 NPs, oxidizer and crosslinker. TEM analysis showed nearly spherical morphology of HmSiO2-F-P(NIPAM-MAm) nanocarrier with a diameter in the range of 100-300 nm. The coating of P(NIPAM-MAm) layer and embedding of Fe3O4 NPs on the surface of the HmSiO2 NPs was revealed by HRTEM analysis. XRD and FTIR analysis also confirmed the presence of P(NIPAM-MAm) shells and Fe3O4 NPs on hollow mesoporous silica NPs. VSM analysis suggested the superparamagnetic nature of HmSiO2-F-P(NIPAM-MAm) nanocarrier. DSC analysis of HmSiO2-F-P(NIPAM-MAm) nanocarrier showed a phase transition at the temperature of ∼38 °C. The prepared HmSiO2-F-P(NIPAM-MAm) nanocarrier was investigated for its suitability for drug-delivery application using doxorubicin as the model drug by an in vitro method. The encapsulation efficiency and encapsulation capacity were found to be 95% and 6.8%, respectively. HmSiO2-F-P(NIPAM-MAm)-Dox has shown a pH and temperature-dependent Dox release profile. A relatively faster release of Dox from the nanocarrier was observed at temperature above the lower critical solution temperature (LCST) than below the LCST. HmSiO2-F-P(NIPAM-MAm) nanocarrier was found to be biocompatible in nature. In vitro cytotoxicity studies against Hela cells suggested that the HmSiO2-F-P(NIPAM-MAm)-Dox nanocomposite nanocarrier has good anticancer activity. In vitro cellular uptake study of HmSiO2-F-P(NIPAM-MAm)-Dox nanocomposite nanocarrier demonstrated its good internalisation ability into Hela cells. Thus, the prepared nanocomposites show potential as nanocarrier for targeted and controlled drug delivery for cancer treatment.

Investigation of novel superparamagnetic Ni0.5Zn0.5Fe2O4@albumen nanoparticles for controlled delivery of anticancer drug.

In the present work, multifunctional Ni0.5Zn0.5Fe2O4@albumen (NZF@Alb) and doxorubicin-loaded Ni0.5Zn0.5Fe2O4@albumen (NZF@Alb-Dox) core-shell nanoparticles have been prepared by a green and simple method using inexpensive chicken egg albumen and have been characterized for different physiochemical properties. The structural, morphological, thermal, and magnetic properties of the prepared nanoparticles have been investigated by an x-ray diffractometer, high-resolution transmission electron microscopy (HRTEM), field emission scanning electron microscopy, Fourier-transformed infrared, thermogravimetric analysis, and vibrating sample magnetometer techniques. Superparamagnetic Ni0.5Zn0.5Fe2O4 nanoparticles (NZF NPs) with the mean size ∼20 nm were coated with albumen matrix by an ultrasonication process. Inverse fast Fourier transform-assisted HRTEM micrographs and FTIR analysis revealed the coating of amorphous albumen on crystalline NZF NPs. NZF@Alb and NZF@Alb-Dox NPs have the mean size (D50) of ∼100 nm, good stability, and magnetic controllability. Magnetic measurements (field (H)-dependent magnetization (M)) show all samples to be super-paramagnetic in nature. Biocompatibilities of the NZF and NZF@Alb NPs were confirmed by in vitro 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay against RAW 264.7 cells. NZF@Alb NPs have been found to be more biocompatible than bare NZF. In Vitro Dox release behavior from NZF@Alb-Dox NPs has been studied at pH 7.4 and 5, and a sustained and pH-dependent drug release profile were observed. In vitro cytotoxicity or anticancer activity of the blank NZF@Alb NPs, free Dox, and NZF@Alb-Dox NPs against HeLa cells (cancer cell line) were also examined by MTT assay. The obtained results suggest that this scalable egg-albumen-based magnetic nanoformulation is suitable for targeted drug delivery applications. Thus, the present study could be extremely useful for the advancement of albumin-based nanocarrier design and development for biomedical applications such as targeted and controlled delivery of anticancer drugs.

Magnetically recyclable Ni0.5Zn0.5Fe2O4/Zn0.95Ni0.05O nano-photocatalyst: structural, optical, magnetic and photocatalytic properties.

A novel visible light active and magnetically separable nanophotocatalyst, Ni0.5Zn0.5Fe2O4/Zn0.95Ni0.05O (denoted as NZF@Z), with varying amount of Ni0.5Zn0.5Fe2O4, has been synthesized by egg albumen assisted sol gel technique. The structural, optical, magnetic, and photocatalytic properties have been studied by powder X-ray diffraction (XRD), transmission electron microscopy (TEM), field emission scanning electron microscopy (FESEM), fourier transform infrared spectroscopy (FTIR), UV-visible (UV-Vis) spectroscopy, and vibrating sample magnetometry (VSM) techniques. Powder XRD, TEM, FTIR and energy dispersive spectroscopic (EDS) analyses confirm coexistence of Ni0.5Zn0.5Fe2O4 and Zn0.95Ni0.05O phases in the catalyst. Crystallite sizes of Ni0.5Zn0.5Fe2O4 and Zn0.95Ni0.05O in pure phases and nanocomposites, estimated from Debye-Scherrer equation, are found to be around 15-25 nm. The estimated particle sizes from TEM and FESEM data are ∼(22±6) nm. The calculated energy band gaps, obtained by Tauc relation from UV-Vis absorption spectra, of Zn0.95Ni0.05O, 15%NZF@Z, 40%NZF@Z and 60%NZF@Z are 2.95, 2.72, 2.64, and 2.54 eV respectively. Magnetic measurements (field (H) dependent magnetization (M)) show all samples to be super-paramagnetic in nature and saturation magnetizations (Ms) decrease with decreasing ferrite content in the nanocomposites. These novel nanocomposites show excellent photocatalytic activities on Rhodamin Dye.