Magnetic Nanogels Research Articles

A sensitive determination of Brilliant Blue FCF in some food samples using hydrophillic deep eutectic solvent-assisted magnetic nano gel-based dispersive solid phase microextraction prior to spectrophotometric analysis

A new magnetic nano gel (MNG) was prepared from choline chloride/phenol deep eutectic solvent and magnetic amberlite XAD-7 nanocomposite. The dispersive solid phase micro extraction (dSPME) method was developed for seperation and preconcentration of Brilliant Blue FCF (BB) by the prepared MNG. In this study, firstly, the optimum DES type and mole ratio of DES were investigated before response surface methodology optimization. Then, the effect of the MNG-dSPME experimental parameters were optimized by response surface methodology using central composite design. Under the optimum microextraction conditions, limit of detection (LOD), limit of quantification (LOQ), preconcentration factor (PF), enhencament factor (EF) were found to be 1.15 μg L−1,3.80 µg L-1, 70, and 88, respectively. It was seen that the recovery of real samples were obtained from 95.5 to 103.6%. The pesent method was succesfully for extraction of BB in some food, personal care samples, to the best of our knowledge, this is the first study that is presented method on determination of BB by preconcentration with magnetic nano gel. The obtained results showed that the present procedure is effective, sensitive, and has high accuracy for the quantitative detection of BB.

Toxicological insight of magnetite nanogel: neuro-ethological, hepato-renal, antioxidant, and histopathological traits in Clarias gariepinus

Assessment of acute toxicity of magnetic nanogel (MNG) is crucial to conclude the safe applicable dose and to warrant its application in aquaculture. Therefore, the current study is a novel step to assess behavior, neuro-stress response, hepato-renal, oxidative, and histopathological variations produced by MNG’ acute toxicity in Clarias gariepinus. Two experiments were conducted: the first was a determination of the 96-h lethal concentration 50 (LC50) of MNG in C. gariepinus. Meanwhile, the second was an assessment of the toxicological impacts of three different concentrations of MNG in C. gariepinus following a 10-day exposure period and a subsequent 10-day depuration trial. One hundred and eighty fish were allotted to four groups exposed to 0, 1/10, 1/8, or 1/5 96-h LC50 of MNG. The outcomes exhibited that 96-h LC50 of MNG for C. gariepinus was 44 mg/L. The subjected group to MNG induced a concentration-dependent elevation in the serum values of cortisol, alanine transaminase, aspartate transaminase, urea, and creatinine following MNG exposure. Marked elevation in the oxidative stress indicators (catalase (CAT), glutathione S-transferase activity (GST), and superoxide dismutase (SOD)) was also evident. Meanwhile, the value of the neurological biomarker, acetylcholinesterase (AChE), was markedly reduced in a concentration-dependent way. These biochemical changes were complemented by pathological alterations in the hepato-renal architecture. Interestingly, in response to the 10-day depuration period, most of the tested parameters were eliminated in C. gariepinus exposed to 1/10 of LC50. Conclusively, MNG can induce numerous adverse effects only at higher doses (1/5 and 1/8 of LC50). Meanwhile, the lowest tested concentration of MNG (1/10 of LC50) was safe for application in aquaculture practices with only mild disruptions in the bio-indices. In addition, a retrieval period of 10 days was sufficient to renovate these alterations only in fish exposed to the same concentration.

The impact of cross-linker distribution on magnetic nanogels: encapsulation, transport and controlled release of the tracer.

Magnetic nanogels (MNGs) are highly attractive for biomedical applications because of their potential for remote control of the rheology and internal structure of these soft colloids with biocompatible magnetic fields. In this contribution, using molecular dynamics simulations, we investigate the impact of the cross-linker distribution in the body of a MNG on the shape and magnetic response to constant and AC magnetic fields and relate those properties to the behaviour of non-magnetic tracers placed in the MNGs and left to escape. We find that if no AC magnetic field is applied, although the escape times of the tracer particles barely depend on morphology, the highest degree of subdiffusion is observed for the gels with a non-uniform cross-linkerer distribution. We also find how the eigen frequency at which particles relax locally in the polymer matrix affects the dynamic magnetic response of the gel. We show that a magnetic field-induced wobbling can facilitate drug release from gels.

Magnetic iron oxide nanogels for combined hyperthermia and drug delivery for cancer treatment.

Hyperthermia and chemotherapy represent potential modalities for cancer treatments. However, hyperthermia can be invasive, while chemotherapy drugs often have severe side effects. Recent clinical investigations have underscored the potential synergistic efficacy of combining hyperthermia with chemotherapy, leading to enhanced cancer cell killing. In this context, magnetic iron oxide nanogels have emerged as promising candidates as they can integrate superparamagnetic iron oxide nanoparticles (IONPs), providing the requisite magnetism for magnetic hyperthermia, with the nanogel scaffold facilitating smart drug delivery. This review provides an overview of the synthetic methodologies employed in fabricating magnetic nanogels. Key properties and designs of these nanogels are discussed and challenges for their translation to the clinic and the market are summarised.

An efficient deep eutectic magnetic nano gel for rapid ultrasound-assisted dispersive µ-solid phase extraction of residue of tetracyclines in food samples.

The online version contains supplementary material available at 10.1007/s13197-023-05798-w.

Protection of Corrosion of Carbon Steel with Core-Shell Inorganic Magnetic Nanogels in Formation Water

Protection of Corrosion of Carbon Steel with Core-Shell Inorganic Magnetic Nanogels in Formation Water

NiFe2O4/polyhydroxymethyl methacrylate and Fe3O4/polyhydroxymethyl methacrylate magnetic nanogels for lipase immobilization

In this study, the optimization and characterization of NiFe2O4/Polyhydroxymethyl methacrylate (NF-pHEMA) and Fe3O4/Polyhydroxymethyl methacrylate (M-pHEMA) magnetic nanogel structures were carried out and the usability of these magnetic nanogels for the immobilization of lipase enzyme was investigated. Fe3O4/pHEMA (M-pHEMA) nanogel and NiFe2O4/pHEMA (NF-pHEMA) nanogel structures were produced by the photochemical method. The characterization of these materials was performed by FTIR, SEM, AFM analysis. Then, the lipase enzyme was immobilized on magnetic nanogels by adsorption and after that cross-linking method under optimum conditions. For the characterization of lipase immobilized magnetic nanogels; optimum temperature, thermal stability, optimum pH, pH stability, reusability and kinetic parameters were investigated and nature and immobilized lipase were compared. It was observed that there was a significant improvement in the thermal and pH stability of the immobilized enzyme compared to the free enzyme. Lipase-immobilized M-pHEMA lost 50% of its activity after 15 uses and after 16 uses of lipase-immobilized NF-pHEMA. The results show that immobilization to the synthesized magnetic nanogels provides an improvement in the properties of the lipase enzyme. It is thought that the synthesized magnetic nanogels can be an alternative for different applications, especially drug delivery systems.

Biocompatibility study of P (N-isopropylacrylamide)-based nanocomposite and its cytotoxic effect on HeLa cells as a drug delivery system for Cisplatin

Cisplatin (CDDP) is widely used as an effective drug in the treatment of various cancers. In spite of its therapeutic effects, there are disadvantages in using CDDP, including causing toxicity in healthy cells, also tumor cells become resistant in prolonged use. The use of magnetic nanogels (nanocomposite), as a drug delivery system, can be a potential strategy to overcome these disadvantages. In this study, the biocompatibility (hemocompatibility and cytocompatibility) of the magnetic, pH, and thermo-responsive poly (N-isopropylacrylamide-co-N, N-dimethylaminoethyl methacrylate-co-4-acrylamidofluorescein)-Fe3O4 nanocomposite was assessed in normal cells. Moreover, we evaluated the cytotoxicity, apoptosis, and drug-resistant genes expression of CDDP-loaded nanocomposite against free CDDP in the cervical cancer cell line (HeLa cells) to investigate its potentials as a vector for drug delivery. The results exhibited that the prepared nanocomposite had an appropriate hemocompatibility. Also, the nanocomposite displayed a good cytocompatibility using LDH test. In addition, the MTT assay of the blank nanocomposite, free CDDP, and CDDP-loaded nanocomposite in the HeLa cells indicated that the blank nanocomposite, had no cytotoxic effects on the cells. However, the Free CDDP and CDDP-loaded nanocomposites demonstrated considerable amount of cytotoxicity effect on the HeLa cells (p < 0.05). The results from the Real Time PCR illustrated that the CDDP-loaded nanocomposite could increase the expression of apoptosis genes and reduce the expression of drug resistance genes in the cancer cells. Our data suggested that the synthetized nanocomposite could be used as an effective and biocompatible drug delivery system for smart delivery and intravenous administration of CDDP. Literature mining-based network discovery proposed candidates for tumor sensitivity/resistance to Cisplatin, viz NR4A1, NR1I2, TP73, and TP53 transcription factors as well as EDN1, CD40LG, INS, and TNFSF11 secreted ligands.

Behaviour of a magnetic nanogel in a shear flow

Magnetic nanogels (MNG) – soft colloids made of polymer matrix with embedded in it magnetic nanoparticles (MNPs) – are promising magneto-controllable drug carriers. In order to develop this potential, one needs to clearly understand the relationship between nanogel magnetic properties and its behaviour in a hydrodynamic flow. Considering the size of the MNG and typical time and velocity scales involved in their nanofluidics, experimental characterisation of the system is challenging. In this work, we perform molecular dynamics (MD) simulations combined with the Lattice-Boltzmann (LB) scheme aiming at describing the impact of the shear rate (γ̇) on the shape, magnetic structure and motion of an MNG. We find that in a shear flow the centre of mass of an MNG tends to be in the centre of a channel and to move preserving the distance to both walls. The MNG monomers along with translation are involved in two more types of motion, they rotate around the centre of mass and oscillate with respect to the latter. It results in synchronised tumbling and wobbling of the whole MNG accompanied by its volume oscillates. The fact the an MNG is a highly compressible and permeable for the carrier liquid object makes its behaviour different from that predicted by classical Taylor-type models. We show that the frequency of volume oscillations and rotations are identical and are growing function of the shear rate. We find that the stronger magnetic interactions in the MNG are, the higher is the frequency of this complex oscillatory motion, and the lower is its amplitude. Finally, we show that the oscillations of the volume lead to the periodic changes in MNG magnetic energy.

Magnetic Drug Navigation: Magnetically Navigated Protein Transduction In Vivo using Iron Oxide‐Nanogel Chaperone Hybrid (Adv. Healthcare Mater. 9/2021)

In article number 2001988 by Yoshihiro Sasaki, Kazunari Akiyoshi, and co-workers, the magnetic nanogel chaperone, comprising of self-assembled polysaccharide nanogels and iron oxide nanoparticles, is developed for magnetically navigated in vivo protein transduction. Magnetic navigation enhances accumulation of the magnetic nanogel chaperone toward tumor tissues. Saporin-loaded magnetic nanogel chaperone exhibits excellent anti-tumor efficacy against oral cancer xenograft mice in vivo.

Dual-responsive biohybrid neutrobots for active target delivery.

Swimming biohybrid microsized robots (e.g., bacteria- or sperm-driven microrobots) with self-propelling and navigating capabilities have become an exciting field of research, thanks to their controllable locomotion in hard-to-reach areas of the body for noninvasive drug delivery and treatment. However, current cell-based microrobots are susceptible to immune attack and clearance upon entering the body. Here, we report a neutrophil-based microrobot ("neutrobot") that can actively deliver cargo to malignant glioma in vivo. The neutrobots are constructed through the phagocytosis of Escherichia coli membrane-enveloped, drug-loaded magnetic nanogels by natural neutrophils, where the E. coli membrane camouflaging enhances the efficiency of phagocytosis and also prevents drug leakage inside the neutrophils. With controllable intravascular movement upon exposure to a rotating magnetic field, the neutrobots could autonomously aggregate in the brain and subsequently cross the blood-brain barrier through the positive chemotactic motion of neutrobots along the gradient of inflammatory factors. The use of such dual-responsive neutrobots for targeted drug delivery substantially inhibits the proliferation of tumor cells compared with traditional drug injection. Inheriting the biological characteristics and functions of natural neutrophils that current artificial microrobots cannot match, the neutrobots developed in this study provide a promising pathway to precision biomedicine in the future.

Magnetically Navigated Protein Transduction In Vivo using Iron Oxide-Nanogel Chaperone Hybrid.

Systems for "protein transduction," intracellular delivery of functional proteins, are needed to address deliverability challenges of protein therapeutics. However, in vivo protein transduction remains challenging because of instability in serum, extracellular protease digestion and rapid excretion from the bloodstream. Here, a magnetically guided in vivo protein transduction using magnetic nanogel chaperone (MC) composed of iron oxide nanoparticles and a polysaccharide nanogel, a protein carrier inspired by "catch and release" mechanisms of molecular chaperones is demonstrated. The MC system enables efficient delivery of anti-cancer proteins, saporin and RNaseA, into cultured tumor lines and inhibits cell proliferation, mainly via apoptosis. Magnetic in vivo protein transduction via intravenous whole body administration is demonstrated in a fibrosarcoma model. By in vivo optical imaging, MC accumulated in tumor tissues under magnetic field three times more than without irradiation. With subcutaneous injection, saporin is delivered by MC to the cytoplasm in magnetically targeted tissues. In an oral cancer model, MC-delivered magnetically targeted saporin decreased tumor volume without significant body weight changes and no regrowth of tumor at 3 months after complete regression. Protein transduction with MC shows promise for cancer therapeutics and, potentially, for regenerative medicine and other biomedical applications.

Tuning the load of gold and magnetic nanoparticles in nanogels through their design for enhanced dual magneto-photo-thermia.

We describe a novel synthesis allowing one to enhance the load of magnetic nanoparticles and gold nanorods in nanogels. Two different structures, simple cores and core-shell, were synthesized and their heating properties upon alternating magnetic field or laser exposure are compared. Remarkably, the core-shell structure showed a greater heating capacity in the two modalities.

Rutin: a Flavonoid Precursor for Synthesis of ZnFe2O4 Nanoparticles; Electrochemical Study of Zinc Ferrite-chitosan Nanogel for Doxorubicin Delivery

The use of core-shell nanoparticles as controlled drug delivery vehicles has proven successful, yet their production and application require costly and toxic chemicals. We hereby use a natural glycosylated flavonoid (rutin) for synthesis of a nanocarrier for doxorubicin delivery. For this target, a convenient two-step synthesis was processed including a synthesis of bio-zinc ferrite nanoparticles without N2 gas and chitosan coating (CS; bio-zincferrite@chitosan). The as-synthesized magnetic nanogel was characterized using scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transformed infrared (FT-IR) spectroscopy, and electro-analytical methods including cyclic voltammetry and electrochemical impedance spectroscopies. The collapse/swell potential of the coated CS layers of the bio-NPs were found to be responsible for the observed pH dependence of doxorubicin delivery. Results exhibited the drug release of bio-nanogel can be induced at pH ranging from 6 to 7. Therefore, capacity and efficiency parameters of the anti-cancer drug onto the NPs were obtained as equal to 43.5% and 78.6%. The present work provides a simple method to fabricate smart pH-responsive nanogel for cancer therapy.

Development of a new magnetic nanogel based on a copolymer of polyacrylic acid-co-acrylamide-co-β-cyclodextrin for extraction/pre-concentration of doxorubicin from biological samples

In this study, a new magnetic nanogel was synthesized for the extraction/pre-concentration of doxorubicin (DOX) from biological samples. The synthesized nano-sorbent was used for the pre-concentration and extraction of DOX prior to spectrophotometry determination. The influence of the main variables, including pH, sorption time, adsorbent amount, and NaCl content, was investigated and optimized by central composite design (CCD) as a response surface methodology. The optimum values obtained for each investigated variable to reach the maximum recovery are pH 5.0, sorption time = 22 min, sorbent amount = 15 mg, and NaCl content = 0%. Under these conditions, the proposed procedure represented good linearity over the range of 0.5–15 µg mL−1 (R2 = 0.9991) for water samples, 2–30 µg mL−1 (R2 = 0.9977) for urine samples, and 0.6–15 µg mL−1 (R2 = 0.9987) for plasma samples. A comparison of the analytical merits of our method with some other published spectroscopic methods for the determination of DOX shows that the developed method is good and comparable with that of other reported methods. The accuracy of the method is confirmed by comparing the results with those obtained by analyzing the samples using a standard method.

The influence of an applied magnetic field on the self-assembly of magnetic nanogels

Using Langevin dynamics simulations, we investigate the self-assembly of magnetic nanogels in the presence of applied magneticfields of moderate strength. We find that even weak fields lead to drastic changes in the structure factors of both, the embeddedmagnetic nanoparticles and of whole nanogel particles. Nanogels assemble by uniting magnetic particle clusters forming inter-gelbridges. At zero field the average amount of such bridges for a pair of nanogels is close to one, whereas even for weak fields itfastly doubles. Rapid growth of cluster size at low values of the applied field is followed by a broad region of slow increase, causedby the mechanical constraints imposed the polymer matrix. The influence of the latter manifests itself in both, the slow growth ofthe magnetisation curve at intermediate fields and the slow decay of the total Zeeman energy.

Doxorubicin Loaded Magnetosensitive Water‐Soluble Nanogel Based on NIPAM and Iron (3+) Containing Nanoparticles

AbstractMagnetosensitive nanogel based on polyacrylic acid, N‐isopropylacrylamide, and magnetic nanoparticles containing Fe3+ is obtained. The size and morphology of the magnetic nanogel are determined. The size and magnetic characteristics of the inorganic phase are established. The anticancer properties of magnetic nanogel loaded by doxorubicin are studied.

Suspensions of magnetic nanogels at zero field: Equilibrium structural properties

Magnetic nanogels represent a cutting edge of magnetic soft matter research due to their numerous potential applications. Here, using Langevin dynamics simulations, we analyse the influence of magnetic nanogel concentration and embedded magnetic particle interactions on the self-assembly of magnetic nanogels at zero field. For this, we calculated radial distribution functions and structure factors for nanogels and magnetic particles within them. We found that, in comparison to suspensions of free magnetic nanoparticles, where the self-assembly is already observed if the interparticle interaction strength exceeds the thermal fluctuations by approximately a factor of three, self-assembly of magnetic nanogels only takes place by increasing such ratio above six. This magnetic nanogel self-assembly is realised by means of favourable close contacts between magnetic nanoparticles from different nanogels. It turns out that for high values of interparticle interactions, corresponding to the formation of internal rings in isolated nanogels, in their suspensions larger magnetic particle clusters with lower elastic penalty can be formed by involving different nanogels. Finally, we show that when the self-assembly of these nanogels takes place, it has a drastic effect on the structural properties even if the volume fraction of magnetic nanoparticles is low.

Magnetically Navigated Intracellular Delivery of Extracellular Vesicles Using Amphiphilic Nanogels

Various cells in vivo secrete exosomes consisting of lipid bilayers. They carry mRNAs and miRNAs capable of controlling cellular functions and can be used as drug delivery system nanocarriers. There is the current need to further improve the efficiency of exosome uptake into target cells. In this study, we prepared a hybrid of exosomes and magnetic nanoparticles, which could be guided to target cells by a magnetic field for efficient uptake. Magnetic nanogels were prepared and hybridized to fluorescently labeled exosomes isolated from PC12 cells. By applying a magnetic field to a hybrid with magnetic nanogel, exosomes were efficiently transferred into target cells as confirmed by confocal laser microscopy. Finally, we found that differentiation of adipose-derived stem cells to neuron-like cells was enhanced by magnetic induction of the exosome-magnetic nanogel hybrid, indicating maintenance of the intrinsic functions of the exosomes in the differentiation of adipose-derived stem cells.

Synthesis and characterization of magnetic dextran nanogel doped with iron oxide nanoparticles as magnetic resonance imaging probe.

Magnetic hybrid nanogels composed of magnetic nanoparticles and polymer hydrogel matrix have drawn much attention because of their unique superparamagnetic properties and biocompatibility as biomaterials. In this study, a facile method was developed for the preparation of iron oxide nanoparticle-loaded magnetic dextran nanogel as magnetic resonance imaging (MRI) probe. Water soluble superparamagnetic iron oxide nanocrystals (Fe3O4) was pre-synthesized and physically doped into a Schiff base-containing dextran nanogel formed using W/O microemulsion as nanoreactor. Magnetic dextran nanogel (Fe3O4@Dex) with particle size of 300-1000 nm was obtained with multiple Fe3O4 nanoparticles randomly encapsulated in the hydrogel networks. Magnetization and T2 relaxivity study shows that the resulted magnetic nanogel has similar superparamagneitc behaviors with single Fe3O4 nanocrystals, and relatively higher T2 relaxivity (277.2 mMFe-1·s-1) as MRI probe. Notably, Schiff base linkages and aldehyde groups on the dextran hydrogel matrix endow the magnetic nanogel with pH-sensitiveness and reactive groups for further modifications, which make the magnetic dextran nanogel a promising nanoplatform as MRI-guided drug delivery system with acid environment-responsiveness.