Bio-Catalysis and Biomedical Perspectives of Magnetic Nanoparticles as Versatile Carriers

Magnetic nanoflowers: a hybrid platform for enzyme immobilization

The use of organic-inorganic hybrid nanoflowers as a support material for enzyme immobilization has gained significant attention in recent years due to their high stability, ease of preparation, and enhanced catalytic activity. However, a major challenge in utilizing these hybrid nanoflowers for enzyme immobilization is the difficulty in handling and separating them due to their low density and high dispersion. To address this issue, magnetic nanoflowers have emerged as a promising alternative enzyme immobilization platform due to their easy separation, structural stability, and ability to enhance catalytic efficiency. This review focuses on different methods for designing magnetic nanoflowers, as well as future research directions. Additionally, it provides examples of enzymes immobilized in the form of magnetic nanoflowers and their applications in environmental remediation, biosensors, and food industries. Finally, the review discusses possible ways to improve the material for enhanced catalytic activity, structural stability, and scalability.

Green nanobiocatalysts: enhancing enzyme immobilization for industrial and biomedical applications

Nanobiocatalysts (NBCs), which merge enzymes with nanomaterials, provide a potent method for improving enzyme durability, efficiency, and recyclability. This review highlights the use of eco-friendly synthesis methods to create sustainable nanomaterials for enzyme transport. We investigate different methods of immobilization, such as adsorption, ionic and covalent bonding, entrapment, and cross-linking, examining their pros and cons. The decreased environmental impact of green-synthesized nanomaterials from plants, bacteria, and fungi is emphasized. The review exhibits the various uses of NBCs in food industry, biofuel production, and bioremediation, showing how they can enhance effectiveness and eco-friendliness. Furthermore, we explore the potential impact of NBCs in biomedicine. In general, green nanobiocatalysts are a notable progression in enzyme technology, leading to environmentally-friendly and effective biocatalytic methods that have important impacts on industrial and biomedical fields.

The Recent Applications of Magnetic Nanoparticles in Biomedical Fields

Magnetic nanoparticles (MNPs) have found extensive application in the biomedical domain due to their enhanced biocompatibility, minimal toxicity, and strong magnetic responsiveness. MNPs exhibit great potential as nanomaterials in various biomedical applications, including disease detection and cancer therapy. Typically, MNPs consist of a magnetic core surrounded by surface modification coatings, such as inorganic materials, organic molecules, and polymers, forming a nucleoshell structure that mitigates nanoparticle agglomeration and enhances targeting capabilities. Consequently, MNPs exhibit magnetic responsiveness in vivo for transportation and therapeutic effects, such as enhancing medical imaging resolution and localized heating at the site of injury. MNPs are utilized for specimen purification through targeted binding and magnetic separation in vitro, thereby optimizing efficiency and expediting the process. This review delves into the distinctive functional characteristics of MNPs as well as the diverse bioactive molecules employed in their surface coatings and their corresponding functionalities. Additionally, the advancement of MNPs in various applications is outlined. Additionally, we discuss the advancements of magnetic nanoparticles in medical imaging, disease treatment, and in vitro assays, and we anticipate the future development prospects and obstacles in this field. The objective is to furnish readers with a thorough comprehension of the recent practical utilization of MNPs in biomedical disciplines.

Recent Trends in Curcumin-Containing Inorganic-Based Nanoparticles Intended for In Vivo Cancer Therapy

Curcumin is a natural compound that has been widely investigated thanks to its various biological properties, including antiproliferative. This molecule acts on different cancers such as lung, breast, pancreatic, colorectal, etc. However, the bioactive actions of curcumin have limitations when its physicochemical properties compromise its pharmacological potential. As a therapeutic strategy against cancer, curcumin has been associated with inorganic nanoparticles. These nanocarriers are capable of delivering curcumin and offering physicochemical properties that synergistically enhance anticancer properties. This review highlights the different types of curcumin-based inorganic nanoparticles and discusses their physicochemical properties and in vivo anticancer activity in different models of cancer.

A novel digitonin/graphene oxide/iron oxide nanocomposite: synthesis, physiochemical characterization and antioxidant activity

In this work, iron oxide (Fe3O4) magnetic nanoparticles (MNPs) and graphene oxide (GO) nanosheets were prepared via the co-precipitation technique and the Modified Hummer method. Fe3O4 MNPs and GO nanosheets were combined to prepare Fe3O4/GO nanocomposite and subsequently conjugated with Digitonin (DIG) in order to obtain a dual-targeted delivery system based on DIG/Fe3O4/GO nanocomposite. SEM images reveal the presence of Fe3O4 MNPs at a scale of 100 nm, exhibiting dispersion between the GO nanosheets. Aggregation of the DIG/Fe3O4/GO nanocomposite was observed at various size scales. The XRD structural analysis confirms the crystal structure of the prepared samples. The Fe3O4 MNPs demonstrated the main XRD-diffracted peaks. Also, GO nanosheets exhibit crystalline characteristics on the (001) and (002) planes. The predominant peaks observed in the DIG/GO/Fe3O4 nanocomposite are attributed to the crystal phases of Fe3O4 MNPs. The FT-IR vibrational modes observed in the GO/DIG/Fe3O4 nanocomposite indicate the presence of crosslinking between GO nanosheet layers and the Fe3O4 MNPs. The antioxidant activity of the prepared samples was measured and the DIG/GO/Fe3O4 nanocomposite demonstrated a significantly high antioxidant activity in both 2-diphenyl-1-picrylhydrazyl (DPPH·) and 2,2-azino-bis-3-ethylbenzthiazoline-6-sulfonic acid (ABTS·+) tests.

How Synthesis of Algal Nanoparticles Affects Cancer Therapy? - A Complete Review of the Literature

The necessity to engineer sustainable nanomaterials for the environment and human health has recently increased. Due to their abundance, fast growth, easy cultivation, biocompatibility and richness of secondary metabolites, algae are valuable biological source for the green synthesis of nanoparticles (NPs). The aim of this review is to demonstrate the feasibility of using algal-based NPs for cancer treatment. Blue-green, brown, red and green micro- and macro-algae are the most commonly participating algae in the green synthesis of NPs. In this process, many algal bioactive compounds, such as proteins, carbohydrates, lipids, alkaloids, flavonoids and phenols, can catalyze the reduction of metal ions to NPs. In addition, many driving factors, including pH, temperature, duration, static conditions and substrate concentration, are involved to facilitate the green synthesis of algal-based NPs. Here, the biosynthesis, mechanisms and applications of algal-synthesized NPs in cancer therapy have been critically discussed. We also reviewed the effective role of algal synthesized NPs as anticancer treatment against human breast, colon and lung cancers and carcinoma.

Greener Syntheses of Coumarin Derivatives Using Magnetic Nanocatalysts: Recent Advances

Coumarins (2H-1-benzopyran-2-ones) are an important group of biological heterocyclic compounds present in various parts of many plant species, encompassing an array of biological and pharmaceutical activities. In view of the importance of coumarins in heterocyclic chemistry and biological sciences and recent advances in the design of magnetic nanocatalysts, we present herein recent developments pertaining to their synthesis exclusively using magnetic nanoparticles, which can be retrieved easily and thus conform to the tenets of greener synthesis. The preparation of various types of coumarins such as Pechmann-based coumarins, bis coumarins, pyranocoumarins, and coumarin derivatives bearing amine moiety, linked to nicotinonitriles, N-coumarin-2-furanone, and pyrrole-linked chromene derivatives using nanocatalysts with a Fe₃O₄ core are described. This review covers the synthetic developments in the recent years 2012-2021 and focuses entirely on the synthesis of coumarins in the presence of magnetic nanocatalysts using greener approaches such as solvent-free conditions or deploying alternative activation methods, namely microwave or ultrasound irradiation.

Immobilization of psychrophile Psychrobacter sp. ANT206 onto novel reusable magnetic nanoparticles and its application for nitro-aromatic compounds biodegradation under low temperature

Efficient biodegradation may offer a solution for the treatment of nitro-aromatic compounds (NACs) with toxicity, mutagenicity and persistence in the environment. In this study, dopamine (DA) functionalized magnetic nanoparticles with biocompatibility and hydrophilicity were synthesized and utilized for the immobilization of nitro-aromatic compounds degrading psychrophile Psychrobacter sp. ANT206 harboring the cold-adapted nitroreductase. The prepared nanocarriers were characterized using multiple methods. The highest immobilization yield of cells immobilized by Fe3O4@SiO2@DA was 90.67% under the optimized conditions of 10 °C, pH 7.5, 2 h and cell/support 1.2 mg/mg, and the activity recovery was 89.41%. In addition, the obtained immobilized cells displayed excellent salinity stability and reusability. Moreover, immobilized P. sp. ANT206 strains showed remarkable biodegradation capability on nitrobenzene and p-nitrophenol. This study introduced those novel Fe3O4@SiO2@DA nanoparticles could be applied as ideal and low-cost nanocarriers for the immobilization of cells and large-scale bioremediation of hazardous NACs with perspective applications under low temperature.

Current Methods for Synthesis and Potential Applications of Cobalt Nanoparticles: A Review

Cobalt nanoparticles (CoNPs) are promising nanomaterials with exceptional catalytic magnetic, electronic, and chemical properties. The nano size and developed surface open a wide range of applications of cobalt nanoparticles in biomedicine along with those properties. The present review assessed the current environmentally friendly synthesis methods used to synthesize CoNPs with various properties, such as size, zeta potential, surface area, and magnetic properties. We systematized several methods and provided some examples to illustrate the synthetic process of CoNPs, along with the properties, the chemical formula of obtained CoNPs, and their method of analysis. In addition, we also looked at the potential application of CoNPs from water purification cytostatic agents against cancer to theranostic and diagnostic agents. Moreover, CoNPs also can be used as contrast agents in magnetic resonance imaging and photoacoustic methods. This review features a comprehensive understanding of the synthesis methods and applications of CoNPs, which will help guide future studies on CoNPs.

Amino Acids, Peptides, and Proteins: Implications for Nanotechnological Applications in Biosensing and Drug/Gene Delivery

Over various scientific fields in biochemistry, amino acids have been highlighted in research works. Protein, peptide- and amino acid-based drug delivery systems have proficiently transformed nanotechnology via immense flexibility in their features for attaching various drug molecules and biodegradable polymers. In this regard, novel nanostructures including carbon nanotubes, electrospun carbon nanofibers, gold nanoislands, and metal-based nanoparticles have been introduced as nanosensors for accurate detection of these organic compounds. These nanostructures can bind the biological receptor to the sensor surface and increase the surface area of the working electrode, significantly enhancing the biosensor performance. Interestingly, protein-based nanocarriers have also emerged as useful drug and gene delivery platforms. This is important since, despite recent advancements, there are still biological barriers and other obstacles limiting gene and drug delivery efficacy. Currently available strategies for gene therapy are not cost-effective, and they do not deliver the genetic cargo effectively to target sites. With rapid advancements in nanotechnology, novel gene delivery systems are introduced as nonviral vectors such as protein, peptide, and amino acid-based nanostructures. These nano-based delivery platforms can be tailored into functional transformation using proteins and peptides ligands based nanocarriers, usually overexpressed in the specified diseases. The purpose of this review is to shed light on traditional and nanotechnology-based methods to detect amino acids, peptides, and proteins. Furthermore, new insights into the potential of amino protein-based nanoassemblies for targeted drug delivery or gene transfer are presented.

Preparation of immobilized arylsulfatase on magnetic Fe3O4 nanoparticles and its application for agar quality improvement

The presence of sulfate groups in agar compromises the agar quality by affecting the crosslinking during gelling process. Some arylsulfatases can catalyze the hydrolysis of sulfate bonds in agar to improve the agar quality. Immobilized arylsulfatases prove beneficial advantages for their industrial applications. Here, a previously characterized mutant arylsulfatase K253H/H260L was immobilized on the synthesized magnetic Fe3O4 nanoparticles after functionalization by tannic acid (MNPs@TA). The surface properties and molecular structures of the immobilized arylsulfatase (MNPs@TA@ARS) were examined by scanning electron microscopy and Fourier transform infrared spectroscopy. Enzymatic characterization showed that MNPs@TA@ARS exhibited shifted optimal temperature and pH with deviated apparent Km and Vmax compared to its free counterpart. The immobilized arylsulfatase demonstrated improved thermal and pH stability and enhanced storage stability with modest reusability. In addition, MNPs@TA@ARS displayed enhanced tolerance to various inhibitors and detergents. The utilization of the immobilized arylsulfatase for agar desulfation brought the treated agar with improved quality.

μSR-Study of a 3% CoFe2O4 Nanoparticle Concentration Ferrofluid

Magnetic fluids based on single-domain magnetic spinel ferrite nanoparticles dispersed in various liquid media are of particular practical and scientific interest. This paper presents a muon spectroscopy study of a ferrofluid based on magnetic nanoparticles of CoFe2O4 molecules dispersed in water (H2O) with a nanoparticle concentration of 3%. In this study, it was determined that the structure and magnitude of the magnetization of a ferrofluid depend on the viscosity of the liquid itself. It was shown that, at room temperature (290 K) and under an external magnetic field of 527 G, the observed additional magnetization was ~20 G. In a small fraction of the sample under study (~20%), negative magnetization (diamagnetism) was observed. At low temperatures (~30 K), the sample acted as a paramagnet in a magnetic field. For the first time, the magnetic field inside and in the immediate vicinity of a CoFe2O4 nanoparticle has been measured experimentally using the μSR method: the value was 1.96 ± 0.44 kG; thus, direct measurement of the magnetization of a nanoscale object was performed.

Biochemical, Ameliorative and Cytotoxic Effects of Newly Synthesized Curcumin Microemulsions: Evidence from In Vitro and In Vivo Studies

Curcumin is known to exhibit antioxidant and tissue-healing properties and has recently attracted the attention of the biomedical community for potential use in advanced therapies. This work reports the formulation and characterization of oil-in-water F127 microemulsions to enhance the bioavailability of curcumin Microemulsions showed a high encapsulation efficiency and prolonged release. To investigate the interactions of curcumin with one unit of the polymeric chain of surfactant F127, ethyl butyrate, and sodium octanoate, as well as the interaction between ethyl butyrate and one unit of the F127 polymer chain, the Density Functional Theory (DFT) calculations at the M06-2X level of theory, were performed in water solution. The MTT assay was used to assess the cytotoxicity of free and encapsulated curcumin on non-malignant and malignant cell lines. Combination effects were calculated according to Chou-Talalay's principles. Results of in vitro studies indicated that MCF7 and HepG2 cells were more sensitive to curcumin microemulsions. Moreover, a synergistic relationship was observed between curcumin microemulsions and cisplatin in all affected fractions of MCF7 and HepG2 cells (CI < 0.9). For in vivo investigation, thioacetamide-intoxicated rats received thioacetamide (100 mg/kg Sc) followed by curcumin microemulsions (30 mg/kg Ip). Thioacetamide-intoxicated rats showed elevated serum liver enzymes, blood urea nitrogen (BUN), and creatinine levels, and a significant reduction in liver superoxide dismutase (SOD) and catalase (CAT) activities (p < 0.05). Curcumin microemulsions reduced liver enzymes and serum creatinine and increased the activity of antioxidant enzymes in thioacetamide-treated rats in comparison to the untreated thioacetamide-intoxicated group. Histopathological investigations confirmed the biochemical findings. Overall, the current results showed the desirable hepatoprotective, nephroprotective, and anti-cancer effects of curcumin microemulsions.

Magnetic micro-macro biocatalysts applied to industrial bioprocesses

The use of magnetic biocatalysts is highly beneficial in bioprocesses technology, as it allows their easy recovering and enhances biocatalyst lifetime. Thus, it simplifies operational processing and increases efficiency, leading to more cost-effective processes. The use of small-size matrices as carriers for enzyme immobilization enables to maximize surface area and catalysts loading, also reducing diffusion limitations. As highly expensive nanoparticles (nm size) usually aggregate, their application at large scale is not recommended. In contrast, the use of magnetic micro-macro (µm-mm size) matrices leads to more homogeneous biocatalysts with null or very low aggregation, which facilitates an easy handling and recovery. The present review aims to highlight recent trends in the application of medium-to-high size magnetic biocatalysts in different areas (biodiesel production, food and pharma industries, protein purification or removal of environmental contaminants). The advantages and disadvantages of these above-mentioned magnetic biocatalysts in bioprocess technology will be also discussed.

Recent developments in enzyme immobilization technology for high-throughput processing in food industries

The demand for food and beverage markets has increased as a result of population increase and in view of health awareness. The quality of products from food processing industry has to be improved economically by incorporating greener methodologies that enhances the safety and shelf life via the enzymes application while maintaining the essential nutritional qualities. The utilization of enzymes is rendered more favorable in industrial practices via the modification of their characteristics as attested by studies on enzyme immobilization pertaining to different stages of food and beverage processing; these studies have enhanced the catalytic activity, stability of enzymes and lowered the overall cost. However, the harsh conditions of industrial processes continue to increase the propensity of enzyme destabilization thus shortening their industrial lifespan namely enzyme leaching, recoverability, uncontrollable orientation and the lack of a general procedure. Innovative studies have strived to provide new tools and materials for the development of systems offering new possibilities for industrial applications of enzymes. Herein, an effort has been made to present up-to-date developments on enzyme immobilization and current challenges in the food and beverage industries in terms of enhancing the enzyme stability.

Saturation of Specific Absorption Rate for Soft and Hard Spinel Ferrite Nanoparticles Synthesized by Polyol Process

Spinel ferrite nanoparticles represent a class of magnetic nanoparticles (MNPs) with enormous potential in magnetic hyperthermia. In this study, we investigated the magnetic and heating properties of spinel soft NiFe2O4, MnFe2O4, and hard CoFe2O4 MNPs of comparable sizes (12–14 nm) synthesized by the polyol method. Similar to the hard ferrite, which predominantly is ferromagnetic at room temperature, the soft ferrite MNPs display a non-negligible coercivity (9–11 kA/m) arising from the strong interparticle interactions. The heating capabilities of ferrite MNPs were evaluated in aqueous media at concentrations between 4 and 1 mg/mL under alternating magnetic fields (AMF) amplitude from 5 to 65 kA/m at a constant frequency of 355 kHz. The hyperthermia data revealed that the SAR values deviate from the quadratic dependence on the AMF amplitude in all three cases in disagreement with the Linear Response Theory. Instead, the SAR values display a sigmoidal dependence on the AMF amplitude, with a maximum heating performance measured for the cobalt ferrites (1780 W/gFe+Co), followed by the manganese ferrites (835 W/gFe+Mn), while the nickel ferrites (540 W/gFe+Ni) present the lowest values of SAR. The heating performances of the ferrites are in agreement with their values of coercivity and saturation magnetization.

Co-immobilization of an Enzyme System on a Metal-Organic Framework to Produce a More Effective Biocatalyst

In many respects, enzymes offer advantages over traditional chemical processes due to their decreased energy requirements for function and inherent greener processing. However, significant barriers exist for the utilization of enzymes in industrial processes due to their limited stabilities and inability to operate over larger temperature and pH ranges. Immobilization of enzymes onto solid supports has gained attention as an alternative to traditional chemical processes due to enhanced enzymatic performance and stability. This study demonstrates the co-immobilization of glucose oxidase (GOx) and horseradish peroxidase (HRP) as an enzyme system on Metal-Organic Frameworks (MOFs), UiO-66 and UiO-66-NH2, that produces a more effective biocatalyst as shown by the oxidation of pyrogallol. The two MOFs utilized as solid supports for immobilization were chosen to investigate how modifications of the MOF linker affect stability at the enzyme/MOF interface and subsequent activity of the enzyme system. The enzymes work in concert with activation of HRP through the addition of glucose as a substrate for GOx. Enzyme immobilization and leaching studies showed HRP/GOx@UiO-66-NH2 immobilized 6% more than HRP/GOx@UiO-66, and leached only 36% of the immobilized enzymes over three days in the solution. The enzyme/MOF composites also showed increased enzyme activity in comparison with the free enzyme system: the composite HRP/GOx@UiO-66-NH2 displayed 189 U/mg activity and HRP/GOx@UiO-66 showed 143 U/mg while the free enzyme showed 100 U/mg enzyme activity. This increase in stability and activity is due to the amine group of the MOF linker in HRP/GOx@UiO-66-NH2 enhancing electrostatic interactions at the enzyme/MOF interface, thereby producing the most stable biocatalyst material in solution. The HRP/GOx@UiO-66-NH2 also showed long-term stability in the solid state for over a month at room temperature.

Magnetic Nanoparticles

Magnetic nanoparticles are a class of nanoparticle that can be manipulated using magnetic fields [...]

Flacourtia indica based biogenic nanoparticles: development, characterization, and bioactivity against wound associated pathogens

Surface engineered nanoparticles (NPs) are of great attention due to their targeted medical applications. The nature of the functionalized surface plays a vital role in achieving the required functionalities of engineered NPs. Owing to the biofilm formation capabilities of wound associated pathogens, impaired wound healing is a major complication in the medical field. In this context, herein, we report the biogenic synthesis of Flacourtia indica (FI) based NPs, i.e., FI-AgNPs using the aqueous leaf extract of this anti-bacterial herb. The newly developed FI-AgNPs were characterized using various analytical and imaging techniques such as UV-Vis spectroscopy, Fourier transform infrared spectroscopy (FT-IR), powder X-ray diffraction (PXRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The FI-AgNPs showed potent anti-microbial activity and anti-biofilm potential which were examined through a test tube adherence method and congo red agar method. It has been observed that synthesized FI-AgNPs inhibit the formation of a biofilm of observed bacteria, even at a minimum concentration of 80 μgml−1. These findings suggest that synthesized FI-AgNPs could be used against wound associated microbes, especially bacterial coating on medical devices, to prevent antibiotic-resistant biofilm infections. Further development and research are obligatory to decode this skill into preventive and therapeutic strategies.