In vitro biological evaluations of Fe3O4 compared with core–shell structures of chitosan-coated Fe3O4 and polyacrylic acid-coated Fe3O4 nanoparticles

Fabrication and characterization of fish gelatin-based magnetic nanocomposite for biomedical applications

Bionanocomposite is considered an advanced way to bridge the gap between the structural and functional material and achieve the desired properties in the nanocomposite. This present study highlighted the synthesis of fish gelatin-based magnetic nanocomposite (GMNC) using three different concentrations of gelatin (6% w/v, G12% w/v, and 18% w/v) individually, through the in situ coprecipitation method. The effect of gelatin concentration on the structural, functional, magnetic properties, and biocompatibility of the GMNC was studied successfully. This variation reduces the crystallite size from 20.8 to 12.2 nm. GMNC obtained at minimum gelatin concentration (6% w/v) produced well-dispersed sphere-shaped magnetite nanoparticles with an average particle size of 33 nm without aggregation. All three reported superparamagnetic behavior at 293 K. It also noted the highly biocompatible and biodegradable nature of GMNC with a high magnetic response at a low magnetic field. This study reported the perspective of this functionalization method for biomedical applications, as GMNC is a potential carrier material that is easily attached to drug molecules through the free functional residues of gelatin molecules. The present study also performed the in vitro drug release behavior of 5'Fluorouracil-loaded GMNC (GF) at physiological conditions (pH 7.4 and 37 °C). It indicates the prepared GF exhibits a sustained drug-release profile for up to 48 h. Hence, these results strongly supported that the functionalized GMNC would be a potential carrier material for advanced drug delivery applications.

Biomass-Derived Core-Shell Carbon Dots with Embedded Tripodal Receptors for the Selective Recognition of Mefenamic Acid in Pharmaceutical Formulations and Urine

A tripodal amine (TPA) with -OH, N, and S donors is synthesized to functionalize a core-shell carbon dot composite (FCDs@SiO2-TPA) for sensing application. The TPA is characterized by spectroscopic and spectrometric techniques, and the composite is characterized by Fourier transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), Brunauer-Emmett-Teller (BET), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and energy-dispersive X-ray spectra (EDS) techniques. The composite has the ability to recognize mefenamic acid (MFA) selectively even in the presence of other drugs like ibuprofen sodium, acetylsalicylic acid, naproxen sodium, diclofenac sodium, and ketoprofen. It can also be used for the quantification of MFA by recording the emission quenching response of the sample at λexc. = 350 nm and λems. = 460 nm (linear range = 1-8 μM and LOD = 197 nM). The density functional theory calculations and 1H NMR titration suggest quenching of the emission signal due to photoinduced electron transfer via hydrogen bonding between the probe and MFA. The composite FCDs@SiO2-TPA has been demonstrated as a reliable and cost-effective sensing probe for the detection of MFA in pharmaceutical formulations, water samples, and cow urine samples.

Fabrication of Curcumin Diethyl γ-Aminobutyrate-Loaded Chitosan-Coated Magnetic Nanocarriers for Improvement of Cytotoxicity against Breast Cancer Cells

This study shows the effectiveness of magnetic-guide targeting in the delivery of curcumin diethyl γ-aminobutyrate (CUR-2GE), a prodrug of curcumin (CUR) previously synthesized to overcome unfavorable physicochemical properties of CUR. In this study, chitosan (Ch)-coated iron oxide nanoparticles (Ch-IONPs) were fabricated and optimized using Box-Behnken design-based response surface methodology for delivery of CUR-2GE. Ch was used as a coating material on the nanoparticle surface to avoid aggregation. The optimized condition for preparing Ch-IONPs consisted of using 4 mg Ch fabricated at pH 11 under a reaction temperature of 85 °C. The optimized Ch-IONPs were successfully loaded with CUR-2GE with sufficient loading capacity (1.72 ± 0.01%) and encapsulation efficiency (94.9 ± 0.8%). The obtained CUR-2GE-loaded Ch-IONPs (CUR-2GE-Ch-IONPs) exhibited desirable characteristics including a particle size of less than 50 nm based on TEM images, superparamagnetic property, highly crystalline IONP core, sufficient stability, and sustained-release profile. In the presence of permanent magnets, CUR-2GE-Ch-IONPs significantly increased cellular uptake and cytotoxicity toward MDA-MB-231 with a 12-fold increase in potency compared to free CUR-2GE, indicating the potential of magnetic-field assisted delivery of CUR-2GE-Ch-IONPs for the treatment of triple-negative breast cancer.

Magnetic nanoparticles applied in targeted therapy and magnetic resonance imaging: crucial preparation parameters, indispensable pre-treatments, updated research advancements and future perspectives

Magnetic nanoparticles (MNPs) have attracted much attention in cancer treatment as carriers for drug delivery and imaging contrast agents due to their distinctive performances based on their magnetic properties and nanoscale structure. In this review, we aim to comprehensively dissect how the applications of MNPs in targeted therapy and magnetic resonance imaging are achieved and their specificities by focusing on the following aspects: (1) several important preparation parameters (pH, temperature, ratio of the reactive substances, etc.) that have crucial effects on the properties of MNPs, (2) indispensable treatments to improve the biocompatibility, stability, and targeting ability of MNPs and prolong their circulation time for biomedical applications, (3) the mechanism for MNPs to deliver and release medicine to the desired sites and be applied in magnetic hyperthermia as well as related updated research advancements, (4) comparatively promising research directions of MNPs in magnetic resonance imaging, and (5) perspectives in the further optimization of their preparations, pre-treatments and applications in cancer diagnosis and therapy.

Spectral drifts in surface textured Fe3O4-Au, core-shell nanoparticles enhance spectra-selective photothermal heating and scatter imaging

We report a significant spectral drift (up to 110 nm) between optical scattering and extinction in magnetite-gold (Fe₃O₄-Au) core-shell nanostructures. The drift was observed experimentally using single-particle broadband dark-field scattering microspectroscopy and solution extinction experiments. Infrared thermography demonstrates an enhanced photothermal activity of these nanoparticles at extinction wavelengths that are far drifted from the wavelengths that produce the best results for imaging via scattering. For example, a relatively smooth gold shell leads to 19% more photothermal activity at 532 nm compared to 690 nm whereas a rough-texture, popcorn type morphology gold shell with three times higher drift, is 170% more efficient at 532 nm. We suggest that the enhanced photothermal response results directly from a reduced competition between absorption and scattering as a consequence of the spectral drift. This spectral drift can be advantageous in multimodal theranostics where therapy and imaging are performed independently at different wavelengths.

Recent Advances in Magnetite Nanoparticle Functionalization for Nanomedicine

Functionalization of nanomaterials can enhance and modulate their properties and behaviour, enabling characteristics suitable for medical applications. Magnetite (Fe3O4) nanoparticles are one of the most popular types of nanomaterials used in this field, and many technologies being already translated in clinical practice. This article makes a summary of the surface modification and functionalization approaches presented lately in the scientific literature for improving or modulating magnetite nanoparticles for their applications in nanomedicine.