Surface modification of super paramagnetic iron oxide nanoparticles via milk casein for potential use in biomedical areas

Simultaneous synthesis of super-paramagnetic hydrochar in a one-pot using subcritical water medium and evaluation of its photocatalytic activity

The unregulated release of chemical dyes into the environment presents considerable environmental hazards when left untreated. Photocatalytic degradation, acknowledged as an eco-friendly and cost-effective method, has garnered attention for its efficacy in eliminating organic pollutants like dye. Consequently, the development of multifunctional materials with different applications in environmental and catalytic fields emerges as a promising avenue. Recognizing the significance of integrating catalysts and porous materials for enhancing interactions between pollutants and photo-sensitive substances, magnetic hydrochar emerges as a solution offering heightened efficiency, scalability, recyclability, and broad applicability in various environmental processes, notably wastewater treatment, due to its facile separation capability. In this study, Fe3O4-based, super-paramagnetic hydrochar (SMHC) was simultaneously synthesized in a single step using a coconut shell in the subcritical water medium. A thorough analysis was conducted on both raw hydrochar (RHC) and SMHC to unravel the mechanism of interaction between Fe3O4 nanoparticles and the hydrochar matrix. The synthesized hydrochar exhibited super-paramagnetic characteristics, with a saturation magnetization of 23.7 emu/g and a magnetic hysteresis loop. SMHC displayed a BET surface area of 42.6 m2/g and an average pore size of 26.3 nm, indicating a mesoporous structure according to nitrogen adsorption-desorption isotherms. XRD analysis revealed magnetic crystal sizes in the obtained SMHC to be 13.7 nm. The photocatalytic performance of SMHC was evaluated under visible light exposure in the presence of H2O2 for Astrazon yellow (AY) dye degradation, with optimization conducted using response surface methodology (RSM). The most substantial dye removal, reaching 92.83%, was achieved with 0.4% H2O2 at a 20 mg/L dye concentration and an 80-min reaction duration.

QbD-driven development and characterization of superparamagnetic iron oxide nanoparticles (SPIONS) of a bone-targeting peptide for early detection of osteoporosis

Osteoporosis is a metabolic disorder that leads to deterioration of bones. The major challenges confronting osteoporosis therapy include early-stage detection and regular disease monitoring. The present studies employed D-aspartic acid octapeptide (-D-Asp-)8 as bone-targeting peptide for evaluating osteoporosis manifestation, and superparamagnetic iron oxide nanoparticles (SPIONs) as nanocarriers for MRI-aided diagnosis. Thermal decomposition technique was employed to synthesize SPIONs, followed by surface-functionalization with hydrophilic ligands. Failure mode effect analysis and factor screening studies were performed to identify concentrations of SPIONs and ligand as critical material attributes, and systematic optimization was subsequently conducted employing face-centered cubic design. The optimum formulation was delineated using desirability function, and design space demarcated with 178.70 nm as hydrodynamic particle size, -24.40 mV as zeta potential, and 99.89 % as hydrophilic iron content as critical quality attributes. XRD patterns ratified lattice structure and SQUID studies corroborated superparamagnetic properties of hydrophilic SPIONs. Bioconjugation of (-D-Asp-)8 with SPIONs (1:1) was confirmed using UV spectroscopy, FTIR and NMR studies. Cell line studies indicated successful targeting of SPIONs to MG-63 human osteoblasts, ratifying enormous bone-targeting and safety potential of peptide-tethered SPIONs as MRI probes. In vivo MRI imaging studies in rats showcased promising contrast ability and safety of peptide-conjugated SPIONs.

Fe3O4SPIONs in cancer theranostics-structure versus interactions with proteins and methods of their investigation

As the second leading cause of death worldwide, neoplastic diseases are one of the biggest challenges for public health care. Contemporary medicine seeks potential tools for fighting cancer within nanomedicine, as various nanomaterials can be used for both diagnostics and therapies. Among those of particular interest are superparamagnetic iron oxide nanoparticles (SPIONs), due to their unique magnetic properties,. However, while the number of new SPIONs, suitably modified and functionalized, designed for medical purposes, has been gradually increasing, it has not yet been translated into the number of approved clinical solutions. The presented review covers various issues related to SPIONs of potential theranostic applications. It refers to structural considerations (the nanoparticle core, most often used modifications and functionalizations) and the ways of characterizing newly designed nanoparticles. The discussion about the phenomenon of protein corona formation leads to the conclusion that the scarcity of proper tools to investigate the interactions between SPIONs and human serum proteins is the reason for difficulties in introducing them into clinical applications. The review emphasizes the importance of understanding the mechanism behind the protein corona formation, as it has a crucial impact on the effectiveness of designed SPIONs in the physiological environment.

Binding ability of roxatidine acetate and roxatidine acetate supported chitosan nanoparticles towards bovine serum albumin: characterization, spectroscopic and molecular docking studies

The RxAc drug loaded on Tween80-chitosan-TPP nanoparticles (NRxAc) has been characterized and probed by UV-Vis, PXRD, FTIR, DLS and SEM technique. The physicochemical characteristics of NRxAc have been employed and evaluated for formulation of drug, particle size, external morphology, drug content and in vitro drug release. Multi-spectroscopic (i.e. fluorescence, UV-Vis, CD spectroscopy) and molecular docking techniques were also used to study the interaction of BSA with RxAc and NRxAc. RxAc and NRxAc quenched the fluorescence emission of BSA via a static quenching mechanism. The experimental data of Fluorescence demonstrated that the binding constant of RxAc and NRxAc were found around 10⁴ L.mol^-1, which suggests moderate binding affinity with BSA via hydrophobic forces. Through the site marker displacement experiments and molecular docking, the probable binding location of RxAc and NRxAc has been suggested in subdomain IB (site III) of BSA. Altogether, the results of present study can provide an important insight and a great deal of helpful information for future design of antiulcer drugs. Hence, The RxAc-loaded chitosan nanoparticles produced might be utilized as a successful tool for developing and using antiulcer drugs.Communicated by Ramaswamy H. Sarma.

Molecular insights into the interaction of 5-fluorouracil and Fe3O4 nanoparticles with beta-casein: An experimental and theoretical study

We investigated the potential carrier of milk beta-casein (β-CN) and its interactions with 5-fluorouracil (5-FU) and iron oxide nanoparticles (Fe₃O₄ NPs). We used different spectroscopic methods of fluorescence, UV-Visble, circular dichroism (CD), synchronous fluorescence, zeta potential assay, and computational studies to clarify the protein interaction with 5-FU and Fe₃O₄ NPs. The fluorescence data indicated both Fe₃O₄ NPs and 5-FU could quench the intrinsic fluorescence of β-CN. Fluorescence measurements showed that the single interaction of β-CN with 5-FU or Fe₃O₄ NPs was static, while reacted β-CN with both 5-FU and Fe₃O₄ NPs simultaneously showed a dynamic quenching. Synchronous fluorescence data in both tests revealed that the tryptophan (Trp) residue of β-CN had a dominant role in quenching and the polarity of its microenvironment more than tyrosine (Tyr) increased in interaction with 5-FU. All the binding sites and thermodynamic parameters were obtained at 25, 37, and 42 °C. The analysis of thermodynamic parameters and Job's plot techniques pointed to that both of these complexes with the 1:1 M ratio were exothermic (ΔH°<0) driven with the van der Waals and H-bonding interactions (in agreement with the docking results). The CD spectra in the region of far-UV and thermal denaturation study indicated minor changes in the secondary structure of β-CN in the presence of various concentrations of Fe₃O₄ NPs and 5-FU. Also, from the molecular dynamics (MD) analysis, as a result, the protein structure was stable during 100 ns. The outcomes highlighted that β-CN protein could form a great bind with 5-FU and Fe₃O₄ NPs ligands (supporting the zeta potential assay results) by independent binding sites. These results would be helpful insight to construct a potential magnetic nanocarrier β-CN base for 5-FU drug delivery.

Anti-microbial and anti-cancer activities of Mn0.5Zn0.5DyxFe2-xO4 (x ≤ 0.1) nanoparticles

Combining two or more nanoparticles is a promising approach. Previously we have reported synthesis of nanoparticles Dysprosium (Dy) substituted with manganese (Mn) zinc (Zn) by using ultrasonication method. The five different nanoparticles (NPs) Mn0.5Zn0.5DyxFe2-xO4 (x ≤ 0.1) have been structurally and morphologically characterized but there is no report on the biological application of these NPs. In the present study, we have examined the anti-cancer, anti-bacterial, and anti-fungal activities of Mn0.5Zn0.5DyxFe2-xO4 (x ≤ 0.1) NPs. Human colorectal carcinoma cells (HCT-116) were tested with different concentrations of NPs by using MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assay. In addition, the impact of NPs was also examined on normal cells such as human embryonic kidney cells, HEK-293. After 48 h of treatment, Mn0.5Zn0.5DyxFe2-xO4 NPs (x = 0.02, 0.04 and 0.06) showed no inhibitory action on cancer cell's growth and proliferation, whereas Mn0.5Zn0.5DyxFe2-xO4 NPs (x = 0.08 and 0.1) showed profound inhibitory action on cancer cell's growth and proliferation. However, the treatment of Mn0.5Zn0.5DyxFe2-xO4 NPs on the normal cells (HEK-293) did not show cytotoxic or inhibitory action on HEK-293 cells. The treatment of Mn0.5Zn0.5DyxFe2-xO4 NPs (x ≤ 0.1) also inhibited both the bacteria (Escherichia coli ATCC35218 and Staphylococcus aureus) with lowest MIC and MBC values of 4 and 8 mg/mL and fungus (Candida albicans) with MIC and MFC values of 4 and 8 mg/mL on treatment with x = 0.08 and 0. 1.

Sol-Gel Synthesis of Dy-Substituted Ni0.4Cu0.2Zn0.4(Fe2-xDyx)O4 Nano Spinel Ferrites and Evaluation of Their Antibacterial, Antifungal, Antibiofilm and Anticancer Potentialities for Biomedical Application

Background

The constant rise of microbial biofilm formation and drug resistance to existing antimicrobial drugs poses a significant threat to community health around the world because it reduces the efficacy and efficiency of treatments, increasing morbidity, mortality, and health-care expenditures. As a result, there is an urgent need to develop novel antimicrobial agents that inhibit microbial biofilm formation.

Methods

The [Ni_0.4Cu_0.2Zn_0.4](Fe_2-xDy_x)O₄(x≤0.04) (Ni-Cu-Zn) nano spinel ferrites (NSFs) have been synthesized by the sol–gel auto-combustion process and were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive x-ray (EDX) and transmission electron microscopy (TEM). The antimicrobial, antibiofilm and antiproliferative activities of Ni-Cu-Zn NSFs were also examined.

Results

The XRD pattern confirms the secondary phase DyFeO₃ and Fe₂O₃ for substituted Dy³⁺ samples, and the crystallite size ranged from 10 to 19 nm. TEM analysis of NSFs revealed that the particles were cube-shaped and 15nm in size. NSFs exhibited significant antimicrobial, antibiofilm and antiproliferative activity. At concentration of 1 mg/mL, it was found that the NSFs (ie, x=0.0, x=0.01, x=0.02, x=0.03 and x=0.04) inhibit biofilm formation by 27.6, 26.2, 58.5, 33.3 and 25% for methicillin-resistant Staphylococcus aureus (MRSA) and 47.5, 43.5, 48.6, 58.3 and 26.6% for Candida albicans, respectively. SEM images demonstrate that treating MRSA and C. albicans biofilms with NSFs significantly reduces cell adhesion, colonization and destruction of biofilm architecture and extracellular polymeric substances matrices. Additionally, SEM and TEM examination revealed that NSFs extensively damaged the cell walls and membranes of MRSA and C. albicans. Huge ultrastructural alteration such as deformation, disintegration and separation of cell wall and membrane from the cells was observed, indicating significant loss of membrane integrity, which eventually led to cell death. Furthermore, it was observed that NSF inhibited the cancer cell growth and proliferation of HCT-116 in a dose-dependent manner.

Conclusion

The current study demonstrated that the synthesized Ni-Cu-Zn NSFs could be used to develop potential antimicrobial surface coatings agents for a varieties of biomedical-related materials and devices in order to prevent the biofilms formation and their colonization. Furthermore, the enhanced antiproliferative properties of manufactured SNFs suggest a wide range of biomedical applications.

Synthesis of Ni0.5Co0.5-xCdxFe1.78Nd0.02O4 (x ≤ 0.25) nanofibers by using electrospinning technique induce anti-cancer and anti-bacterial activities

Here we report the electrospinning synthesis of Cd-substituted Ni-Co ferrite Ni_0.5Co_0.5-xCd_xFe_1.78Nd_0.02O₄ (x ≤ 0.25) nanofiber (NFs) with a very low concentration of Nd as a dopant. The structure and surface morphology of the Ni_0.5Co_0.5-xCd_xFe_1.78Nd_0.02O₄ (x ≤ 0.25) NFs were analyzed by X-ray powder pattern (XRD), transmission and scanning electron microscopes (TEM) along with Energy-dispersive X-ray (EDX). We have examined the biological applications of the Ni_0.5Co_0.5-xCd_xFe_1.78Nd_0.02O₄ (x ≤ 0.25) NFs on both cancerous cells and bacterial cells. We have found that Ni_0.5Co_0.5-xCd_xFe_1.78Nd_0.02O₄ (x ≤ 0.25) NFs produced inhibitory action on the human colorectal carcinoma cells (HEK-293) and also showed inhibitory action on the bacterial strains (S. aureus and E. coli) respectively. Finally, this is the first report on the synthesis of Cd- substituted Co-Ni ferrite nanofibers using electrospinning technique exhibiting anti-cancer and anti-bacterial activities.Communicated by Ramaswamy H. Sarma.

Synthesis of niobium substituted cobalt-nickel nano-ferrite (Co0.5Ni0.5NbxFe2-xO4 (x ≤ 0.1) by hydrothermal approach show strong anti-colon cancer activities

The combination of two or more nanoparticles found to be effective strategy to synthesize nanocomposites for better drug delivery and treatment. In the present study, we have combined cobalt (Co), nickel (Ni), niobium (Nb), and iron oxide (Fe₂O₄) and prepared niobium substituted cobalt-nickel nano-ferrite nanocomposites (Co_0.5Ni_0.5Nb_xFe_2-xO₄ (x ≤ 0.1) by using hydrothermal approach. We have characterized the structure and morphology of nanocomposites by using XRD, EDX, TEM and SEM methodologies. We have examined the impact of nanocomposites (Co_0.5Ni_0.5Nb_xFe_2-xO₄ (x ≤ 0.1) on cancerous cells (human colorectal carcinoma cells, HCT-116) by using MTT assay. We have also checked the impact of nanocomposites on normal and non-cancerous cells (human embryonic kidney cells, HEK-293) to confirm the specificity of their actions. Post- 48 h treatment of Co_0.5Ni_0.5Nb_xFe_2-xO₄ (x ≤ 0.1) led to dose-dependent inhibition of cancer cells growth and proliferation. However, no cytotoxic effect was observed on the normal cells (HEK-293). In addition, DAPI stained nuclear DNA staining analysis demonstrates that the Co_0.5Ni_0.5Nb_xFe_2-xO₄ (x ≤ 0.1) treatment also caused nuclear DNA disintegration which is the marker for programmed cell death. These results demonstrate that synthesized nanocomposites Co_0.5Ni_0.5Nb_xFe_2-xO₄ (x ≤ 0.1) selectively target the colon cancer cells and induce cancer cell death.Communicated by Ramaswamy H. Sarma.