Institute of Fundamental Technological Research

This work presents the synthesis and characterization of a composite made of superparamagnetic iron oxide and hydroxyapatite nanoparticles (SPION/HAp) with a well-developed surface for loading anticancer drugs and for use in magnetic hyperthermia and local chemotherapy. The proposed material was obtained by an easy one-pot co-precipitation method with a controlled ratio of SPION to HAp. The morphology was studied by SEM and TEM, indicating rod-like structures for high HAp content in the composite and granule-like structures with increasing SPION. Its crystallinity, elemental composition, and functional groups were determined by X-ray diffraction, EDS, and FT-IR, respectively. The nanocomposite was then stabilized with citrates (CA), polyethylene glycol (PEG), and folic acid (FA) as agents to improve intracellular absorption, while turbidimetric studies confirmed that only citrates effectively stabilized the magnetic carriers to form a colloidal suspension. Subsequently, 5-fluorouracil (5-FU) was loaded into the magnetic carriers and tested in vitro using the L-929 cell line. The studies showed no cytotoxicity of the citrate-stabilized suspension against fibroblasts and some cytotoxicity after 5-FU release. In addition to in vitro studies, the composite was also tested on biomimetic membranes made of DOPC, DOPE, cholesterol, and DOPS lipids using Langmuir trough. The results show that the resulting suspension interacts with biomimetic membranes, while magnetic hyperthermia studies confirm effective heat generation to achieve therapeutic 42–46 °C and improve drug release from magnetic carriers.

SPION, Hydroxyapatite, Magnetic hyperthermia, Drug delivery, 5-fluorouracil, Biomimetic membranes, Nanostructures, Cancer treatment

Adsorption,Thermal desorption,Gd-doped Fe3O4,Methotrexate

In this study, eco-friendly Fe3O4-lignin (FeL) and Fe3O4-carbon-based lignin (FeCL) were synthesized, characterized, and applied for the adsorption of tetracycline (TRC) and ceftriaxone (CEF). Comparative characterization showed that the BET-specific surface area of FeCL is 27 m2/g more than that of FeL. The difference in their morphologies is insignificant, and the particle sizes range between 5 and 15 nm. There is a reduction in the oxygen content and hydroxyl group of FeCL as shown from the EDS and FTIR spectra respectively, compared with FeL. The adsorption capacity for the removal of TRC at 333 K is 156 and 148 mg g−1 by FeL and FeCL, respectively; while that of CEF are virtually the same. FeL and FeCL adsorption capacity for TRC increases with temperatures (endothermic), but decreases (exothermic) for CEF. The combination of experimental and computational approaches gave insight into the mechanisms of the adsorption process. The mechanisms of TRC and CEF adsorption by FeL and FeCL are the electrostatic attraction, hydrophobic, and π-π interaction, while only FeL shows the possibility of hydrogen bond with both TRC and CEF. The study demonstrated that the synthesized material can be reused for up to 3 cycles without an alarming loss of efficiency capacity.
Graphical abstract

Lignin,antibiotics,Adsorption mechanisms,Thermodynamics

Adsorption and photocatalytic degradation techniques for removing various contaminants have received broad consideration and acceptance due to their advantages over conventional wastewater treatment techniques. Iron- based materials are among several groups of adsorbents, and photocatalysts that have proven to be effective in pharmaceuticals-based pollutants removal from wastewater. Pharmaceutical drug removal is accompanied by several mechanisms, so there is a deep need for a better understanding of the complexity and development of wastewater treatment using iron-based materials. Therefore, this review examined the mechanism of adsorption
and photocatalysis degradation of pharmaceuticals in aqueous solutions by iron-based materials. The adsorption of pharmaceutical drugs was found to be influenced by changes in the solution pH. The mechanism of removal of
these contaminants by iron-based materials through adsorption occurred via electrostatic, π-π, and hydrogen bond interactions among others. In the case of photocatalysis, the first mechanism occurred through the for-
mation the hydroxyl radicals due to highly reactive species (electrons and holes) that partook in the reaction processes, while the second mechanism is related to the formation of hydrogen peroxide, H2O2, by photo-
generated electrons in the conduction band and with the well-known photo dissolution of iron oxide leading to free Fe2+ and Fe3+ ions. The overall idea of this review is to provide useful information on the mechanisms of
adsorption and photocatalytic degradation of pharmaceutical contaminants using iron-based materials. The re-view summarizes the current understanding and the advances in the pharmaceutical-bearing effluent treatment using nanostructured adsorbents and photocatalysts, including future developments for a cleaner and safer environment.

Mechanism,Iron-based materials,Pharmaceutical drugs,Adsorption,Photo(degradation)

Commendable efforts have been gingered towards the fight against cancer. Nevertheless, it remains a major public health concern due to its predominant cause of death globally. Given this, we synthesized two different nanoparticles, Sr2+ and Gd3+ doped magnetite for magnetic hyperthermia and drug delivery application. Based on the characterization, the diffractogram shows that only one phase related to magnetite with a crystallite size of 10 nm was formed. TEM images revealed nanoparticles of spherical shapes of approximately 12 nm. There is no difference in magnetic saturation of the as-received synthesized samples (Fe3O4@Sr and Fe3O4@Gd), while the BET-specific surface area of Fe3O4@Gd is 8 m2 g−1 higher than Fe3O4@Sr. The heat generation in alternating magnetic field (the magnetic hyperthermia) of Fe3O4@Sr functionalized with citric acid and loaded with 5- fluorouracil (Fe3O4@Sr@CA@5-flu) is slower than Fe3O4@Gd@CA@5-flu. The specific absorption rate (SAR) of Fe3O4@Gd@CA@5-flu, 112.0 ± 10.4 W g−1 was found to be higher than that of Fe3O4@Sr@CA@5-flu. The thermogram shows that 11% of the drug was successfully loaded on Fe3O4@Gd@CA@5-flu. The release of the antitumor drug by the synthesized nanoparticle drug carriers for ovarian cancer (SKOV-3 cells) therapy showed that more than 50% of the cancer cell’s viability was reduced after 72 h of incubation. The synthesized nanoparticles demonstrated a promising drug carrier for the treatment of SKOV-3 cells.

In this work, we present magnetic nanoparticles based on iron oxide doped with zinc syn-
thesized using the wet co-precipitation method for environmental application. The morphology of the
samples was revealed by SEM and TEM, which showed particles of granular shape and size of about
15 nm. The specific surface areas of the materials using the BET method were within the range of 85.7 to 101.5 m2 g−1 depending on the zinc content in the superparamagnetic iron oxide nanoparticles (SPI-ONs). Magnetometry was performed to determine the magnetic properties of the particles, indicating superparamagnetism. Synthesized magnetic nanoparticles with different amounts of zinc dopant were used as an adsorbent to remove model pollutant Titan yellow (TY) from the aqueous solutions. Adsorption was determined by investigating the effects of sorbent amount, dye concentration, and contact time. The synthesized material removed Titan yellow quickly and efficiently within the phys-ical adsorption. The adsorption isotherms were consistent with the models proposed by Langmuir and Redlich-Peterson. The monolayer adsorption capacities were 30 and 43 mg g−1 for Fe3O4 and Fe3O4@10%Zn, respectively, for the removal of TY. However, that of Congo red is 59 mg g−1 by Fe3O4@10%Zn. The proposed nanoparticles offer fast and cost-effective water purification, and they can be separated from solution using magnets.

perparamagnetic particles, pollution treatment, Titan yellow, Congo red, adsorption isotherm, iron oxide

maghemite,tetracycline,adsorption,photocatalysis,mechanism,eco-friendly water treatment