Mesoporous superparamagnetic hydroxyapatite nanocomposite: A multifunctional platform for synergistic targeted chemo-magnetotherapy

Magnetic Hydroxyapatite Nanoparticles in Regenerative Medicine and Nanomedicine

This review focuses on the latest advancements in magnetic hydroxyapatite (mHA) nanoparticles and their potential applications in nanomedicine and regenerative medicine. mHA nanoparticles have gained significant interest over the last few years for their great potential, offering advanced multi-therapeutic strategies because of their biocompatibility, bioactivity, and unique physicochemical features, enabling on-demand activation and control. The most relevant synthetic methods to obtain magnetic apatite-based materials, either in the form of iron-doped HA nanoparticles showing intrinsic magnetic properties or composite/hybrid compounds between HA and superparamagnetic metal oxide nanoparticles, are described as highlighting structure-property correlations. Following this, this review discusses the application of various magnetic hydroxyapatite nanomaterials in bone regeneration and nanomedicine. Finally, novel perspectives are investigated with respect to the ability of mHA nanoparticles to improve nanocarriers with homogeneous structures to promote multifunctional biological applications, such as cell stimulation and instruction, antimicrobial activity, and drug release with on-demand triggering.

A dual catalytic functionalized hollow mesoporous silica-based nanocarrier coated with bacteria-derived exopolysaccharides for targeted delivery of irinotecan to colorectal cancer cells

In this study, we introduced a multifunctional hollow mesoporous silica-based nanocarrier (HMSN) for the targeted delivery of irinotecan (IRT) to colorectal cancer cells. Due to their large reservoirs, hollow mesoporous silica nanoparticles are suitable platforms for loading significant amounts of drugs for sustained drug release. To respond to pH and redox, HMSNs were functionalized with cerium and iron oxides. Additionally, they were coated with bacterial-derived exopolysaccharide (EPS) as a biocompatible polymer. In vitro analyses revealed that cytotoxicity induced in cancer cells through oxidative stress, mediated by mature nanocarriers (EPS.IRT.Ce/Fe.HMSN), was surprisingly greater than that caused by free drugs. Cerium and iron ions, in synergy with the drug, were found to generate reactive oxygen species when targeting the acidic pH within lysosomes and the tumor microenvironment. This, in turn, triggered cascade reactions, leading to cell death. In vivo experiments revealed that the proposed nanocarriers had no noticeable effect on healthy tissues. These findings indicate the selective delivery of the drug to cancerous tissue and the induction of antioxidant effects due to the dual catalytic properties of cerium in normal cells. Accordingly, this hybrid drug delivery system provides a more effective treatment for colorectal cancer with the potential for cost-effective scaling up.

DOX-loaded mesoporous hydroxyapatite modified by hyaluronic acid can achieve efficient targeted therapy for lung cancer

It is a novel therapeutic strategy to suppress tumour growth and metastasis by regulating the interaction between bioactivity ions and the biological process of tumour cells. This study synthesised a mesoporous hydroxyapatite (MHAP)-based nanocarrier for targeted delivery of the anti-cancer drug doxorubicin (DOX). To further strengthen the targeting of DOX-loaded nanocarrier to tumour, HA that could specifically identify receptor on the surface of tumours was functionally modified. The drug release properties curve showed that the MHAP-HA@DOX complex showed pH-sensitive and sustained release properties. Also, the MHAP-HA@DOX complex represented high toxicity against lung cancer A549 cells. Besides, it displayed a significant inhibitory effect on tumour growth rate in tumour-bearing mice, while no evident toxicity for mice was observed. This nano-material is hoped to be an effective and novel nano-drug for lung cancer.

Evaluation of drug release, monomer conversion and surface properties of resin composites containing chlorhexidine-loaded mesoporous and nonporous hydroxyapatite nanocarriers

The aim of this study was to evaluate drug release, degree of conversion (DC), and surface properties of resin composites containing chlorhexidine (CHX)-loaded mesoporous (mHAP) and nonporous hydroxyapatite (HAP) nanocarrier. CHX loaded mHAP and HAP, or CHX without nanocarrier was added into the resin composite in 1% and 5% concentrations. After characterization of experimental materials with XRD, EDX, FT-IR, and SEM, the CHX release on the 1st, 7th, 30th, and 120th days were evaluated by UV-vis spectroscopy. DC, surface roughness, and surface hardness of the samples were also evaluated. The data was statistically analyzed. While mHAP groups released significantly higher CHX on the 30th day (p < .05), there was no statistically significant difference between the HAP and mHAP groups on the 120th day (p > .05). DCs of all groups were similar (p > .05). While mHAP and HAP groups containing 5% CHX showed significantly higher roughness than the other groups (p < .05), no statistically significant difference was observed between the other groups (p > .05). The 1% and 5% CHX groups without nanocarrier showed significantly lower surface hardness (p < .05). However, no statistically significant difference was observed between the other groups in terms of surface hardness (p > .05). A controlled CHX release was achieved by mHAP and HAP nanocarriers for 120 days. The nanocarrier addition up to 5% did not negatively affect the DC and the surface hardness which is one of the surface properties of the resin composites. Although the addition of 5% nanocarrier to the resin composite increased the surface roughness, while adding 1% of these nanocarriers did not change.

Synergistic Effect Evaluation of Magnetotherapy and a Cationic-Magnetic Nanocomposite Loaded with Doxorubicin for Targeted Drug Delivery to Breast Adenocarcinoma

This work investigates the synergistic effect of magnetotherapy and a novel cationic-magnetic drug delivery system on inhibiting breast cancer cell growth and other tissues. First, super-paramagnetic magnetite (Fe₃O₄) nanoparticles were coated with doxorubicin-imprinted poly(methacrylic acid-co-diallyl dimethylammonium chloride) [Fe₃O₄/poly(MAA-DDA)]. The cationic-magnetic nanocomposite (CMC) was characterized using XRD, FT-IR, VSM, TGA, TEM, FESEM, EDS, DLS, and BET. In vitro analyses, including drug release kinetics, cytotoxicity, and hemolytic assays, confirmed this novel CMC's good drug release profile and biocompatibility. Finally, in vivo experiments on BALB/c mice were designed to evaluate the synergistic effect of magnetotherapy on targeted drug delivery using the CMC. In vivo fluorescence imaging evaluated the drug distribution in different tissues of mice. Tumor volume evaluation demonstrated the efficiency of the CMC and magnetotherapy in preventing tumor growth; the two techniques significantly reduced tumor volume. Histopathological analysis proved that applying magnetotherapy in conjunction with the cationic-magnetic drug delivery system significantly prevented tumor cell proliferation and increased apoptosis with limited impact on other tissues. Also, Dox and Fe concentrations in different tissues confirmed the efficient drug delivery to tumor cells.

Hydroxyapatite Biobased Materials for Treatment and Diagnosis of Cancer

Great advances in cancer treatment have been undertaken in the last years as a consequence of the development of new antitumoral drugs able to target cancer cells with decreasing side effects and a better understanding of the behavior of neoplastic cells during invasion and metastasis. Specifically, drug delivery systems (DDS) based on the use of hydroxyapatite nanoparticles (HAp NPs) are gaining attention and merit a comprehensive review focused on their potential applications. These are derived from the intrinsic properties of HAp (e.g., biocompatibility and biodegradability), together with the easy functionalization and easy control of porosity, crystallinity and morphology of HAp NPs. The capacity to tailor the properties of DLS based on HAp NPs has well-recognized advantages for the control of both drug loading and release. Furthermore, the functionalization of NPs allows a targeted uptake in tumoral cells while their rapid elimination by the reticuloendothelial system (RES) can be avoided. Advances in HAp NPs involve not only their use as drug nanocarriers but also their employment as nanosystems for magnetic hyperthermia therapy, gene delivery systems, adjuvants for cancer immunotherapy and nanoparticles for cell imaging.

PEGylated Magnetite/Hydroxyapatite: A Green Nanocomposite for T2-Weighted MRI and Curcumin Carrying

Background

The design of new magnetic resonance imaging (MRI) contrast media with chemotherapy drug-carrying capacity has an important role in diagnostic and therapeutic purposes. This study aimed to synthesize a polyethylene glycol (PEG)-coated magnetite/hydroxyapatite nanocomposite as an MRI contrast agent investigate its curcumin loading/release properties and consider the cytotoxicity effect of the curcumin-loaded nanocomposite on different cell lines.

Materials and Methods

PEGylated magnetite/hydroxyapatite (PMHA) nanocomposite was synthesized and characterized using X-ray diffraction, Fourier transform infrared spectroscopy, transmission electron microscopy, vibrating sample magnetometry, and energy dispersive X-ray analysis. MTT assay was performed to consider the A549, MCF-7, and MRC-5 cells toxicity of the PMHA and the curcumin-loaded nanocomposite. The r2 relaxivity of the nanocomposite was determined by an MRI device. The curcumin loading and its release from the nanocomposite at pH of 7.4 and 5.5 were investigated.

Results

The spherical nanocomposite showed an average size of 20 nm and a superparamagnetic property. PMHA nanocomposite was highly cytocompatible, while the curcumin-loaded nanocomposite showed significant cytotoxicity for A549 and a much higher toxic effect on MCF-7 cancer cells. The r2 relaxivity was measured as 120 mM⁻¹S⁻¹. The curcumin loading capacity of PMHA was 1.9 mg/g, and the curcumin release profile showed a pH-dependent sustained release of the anti-cancer drug that was higher for pH of 5.5.

Conclusion

The high r2 relaxivity of PMHA nanocomposite and sustained release of curcumin from the loaded one at the pH of tumor environment suggest that the nanocomposite is a potential candidate for T2-weighted MRI and cancer treatment.

Inorganic Nanoparticles in Bone Healing Applications

Modern biomedicine aims to develop integrated solutions that use medical, biotechnological, materials science, and engineering concepts to create functional alternatives for the specific, selective, and accurate management of medical conditions. In the particular case of tissue engineering, designing a model that simulates all tissue qualities and fulfills all tissue requirements is a continuous challenge in the field of bone regeneration. The therapeutic protocols used for bone healing applications are limited by the hierarchical nature and extensive vascularization of osseous tissue, especially in large bone lesions. In this regard, nanotechnology paves the way for a new era in bone treatment, repair and regeneration, by enabling the fabrication of complex nanostructures that are similar to those found in the natural bone and which exhibit multifunctional bioactivity. This review aims to lay out the tremendous outcomes of using inorganic nanoparticles in bone healing applications, including bone repair and regeneration, and modern therapeutic strategies for bone-related pathologies.

Mg.ATP-decorated ultrafine magnetic nanofibers: A bone scaffold with high osteogenic and antibacterial properties in the presence of an electromagnetic field

In this study, ultrafine magnetic nanofibers were developed for bone regeneration purposes. Nanofibers were acquired by electrospinning using a two-component nanofiber matrix (CP: chitosan (Cs) and polyvinyl alcohol (PVA)) containing different concentrations of succinate conjugated-magnetic hydroxyapatite nanocomposites (SMHA). Hybrid nanofibers (CP&SMHA) containing 5 mg ml^-1 of SMHA nanocomposite showed well-defined properties in terms of physicochemical properties and cell behavior. Then, they were modified with adenosine 5'-triphosphate (ATP) and Mg²⁺ ions. The initial adhesion of mesenchymal stem cells and their proliferation rate on the surface of modified nanofibers (Mg.ATP.CP&SMHA) were significantly increased as compared to those of bare nanofibers. Analysis of common osteogenic markers such as alkaline phosphatase activity and the expression of Runt-related transcription factor 2 and osteocalcin confirmed the osteogenic efficacy enhancement of CP&SMHA nanofibers when they were functionalized with ATP and Mg²⁺. The utilization of the antagonist of purine receptor, P2X7, revealed that this receptor has a major role in the osteogenesis process induced by Mg.ATP.CP&SMHA. Moreover, the results showed that cell adhesion, proliferation, and differentiation improved as nanofibers were under the influence of the electromagnetic field (EMF), displaying synergistic effects in the process of bone formation. Mg.ATP.CP&SMHA also showed an antibacterial effect against gram-negative and gram-positive bacteria, Escherichia coli and Staphylococcus aureus, respectively. Considering the high osteogenic potential and antibacterial activity of Mg.ATP.CP&SMHA nanofibers particularly in combination with EMF, it can serve as a great candidate for use in bone tissue engineering applications.

Progress of biomaterials for bone tumor therapy

Bone tumors are currently a major clinical challenge. In recent decades, strategies using well-designed versatile biomaterials for the treatment of bone tumors have emerged and attracted extensive research interest. Suitable biomaterials not only facilitate repair for bone defects aroused by surgical intervention but also help deliver antineoplastic drugs to the target site or provide photothermal/magnetothermal therapy to kill bone tumor cells. Thus, the development of biomaterials exhibits a great perspective for future bone tumor treatment.We summarize the recent progress of versatile biomaterials for bone tumor therapy, with an emphasis on photothermal/magnetothermal therapy and drug delivery.With the further understanding and development of biomaterials, multifunctional biomaterials have been proposed for bone tumor treatment. Through the interdisciplinary cooperation from the fields of biomedicine, clinical medicine and engineering, multifunctional biomaterials will perfectly match individual bone defects in the clinic with low cost in the future.

Fenton-magnetic based therapy by dual-chemodrug-loaded magnetic hydroxyapatite against colon cancer

Fenton-based therapy is emerging as an effective and selective strategy against cancer. However, a low concentration of transition metal ions, insufficient endogenous H₂O_2, and a high level of antioxidant activity within the cancer cells have hindered the therapeutic efficacy of this strategy. To address these issues, in this study, the Fenton reagent (magnetic hydroxyapatite, mHAP) was accompanied with chemotherapy drugs (cisplatin (CDDP) and methotrexate (MTX)) and static magnetic field (SMF), in such a way to be a pH-, redox-, and magnetic-responsive nanoplatform. In vitro and in vivo experiments revealed higher toxicity of the final construct, MTX.CDDP@mHAP, toward colon cancer cells, as compared with that of free drugs. The most effective antitumor activity was observed as MTX.CDDP@mHAP-treated tumor cells were exposed to SMF (0.9 T) and no noticeable damage was observed in the normal cells and tissues. Active targeting by MTX and magnetic targeting by mHAP under magnetic field increased the tumor selectivity and enhanced the tumor site accumulation and cellular uptake of MTX.CDDP@mHAPs. The released iron ions within the cancer cells trigger the Fenton reaction while the release of chemotherapy drugs, reduction of intracellular glutathione, and application of SMF aggravated the Fenton reaction, subsequently leading to the generation of reactive oxygen species (ROS) and induction of apoptosis. Therefore, Fenton magnetic-based therapy-mediated by MTX.CDDP@mHAP could be considered as a promising strategy against colon cancer with high therapeutic efficiency and biosafety.

Hydroxyapatite with magnetic core: Synthesis methods, properties, adsorption and medical applications

This review presents the actual state of knowledge and recent research results on the magnetic composite synthesized from iron oxide (γ-Fe₂O₃ or Fe₃O₄) and hydroxyapatite. It can be obtained applying some methods, i.e. chemical precipitation, hydrothermal, sol-gel, and biomimetic or combined techniques which exhibit characteristic properties affecting the form of the prepared product. More specific details are discussed in this paper. A comparison of the discussed synthesis methods is presented. On the basis of selected publications, a comparison of the results of the analysis by XRD, FTIR, SEM and EDX methods for hydroxyapatite with a magnetic core was also presented. Moreover, the characteristics large adsorption capacity and specific area allow employing nanocomposites as adsorbents particularly in removal of toxic metal ions. Nowadays this issue is extremely vital due to large amounts of pollutants in the environment and greater ecological awareness of people. Moreover, magnetic hydroxyapatite can be also applied as a catalyst in various syntheses or oxidation reactions as well as in medicine in magnetic resonance imaging, hyperthermia treatment, drug delivery and release, bone regeneration or cell therapy.

Induction of osteogenesis in bone tumour cells by purine-conjugated zinc-hydroxyapatite

This study aimed to improve the biocompatibility and osteogenic property of hydroxyapatite (HAP). So HAP nanoparticles were doped with zinc (Zn), and their surface was modified with a purine nucleotide, guanosine 5′-triphosphate (GTP). GTP-loaded nanoparticles (GTP@ZnHAP) were characterised by field emission scanning electron microscopy, Fourier transform infrared, thermogravimetric analysis, zeta potential and ultraviolet–visible spectroscopy. Biological experiments revealed that GTP@ZnHAP nanoparticles were internalised by the cells, inhibiting tumour cell (osteoblast-like cells, Saos-2) expansion with an efficiency more than that observed for ZnHAP nanoparticles and GTP alone. Furthermore, Saos-2 cells were committed to differentiate into the normal osteoblast cells under the influence of GTP@ZnHAP nanoparticles demonstrated by the quantitative assessment of bone-related protein expression (Runx2 and osteocalcin) and cell morphological changes. Moreover, high-performance liquid chromatography analyses disclosed a significant enhancement of intracellular GTP content in GTP@ZnHAP-treated cells, proposing perturbation of intracellular nucleotide equilibrium during the process of osteogenesis induced by GTP@ZnHAP nanoparticles. Overall, GTP@ZnHAP exhibits a better synergistic effect on the modulation of cell growth and induction of osteogenic differentiation in osteosarcoma cells than ZnHAP nanoparticles and GTP alone do. Therefore, GTP@ZnHAP may be regarded as a promising biomaterial for the treatment of bone-related diseases.

Design strategies and evolving role of biomaterial assisted treatment of osteosarcoma

Osteosarcoma is the most commonly diagnosed form of bone cancer. It is characterized by a high risk of developing lung metastasis as the disease progresses. Standard treatment includes combination of surgical intervention, chemotherapy and radiotherapy. However, the non-specificity of potent chemotherapeutic agents often leads to major side effects. In this review, we discuss the role of various classes of biomaterials, including both organic as well as inorganic in realizing the local and systemic delivery of therapeutic agents like drugs, radioisotopes and even gene silencing agents to treat osteosarcoma. Biomaterial assisted unconventional therapies such as targeted therapy, nanotherapy, magnetic hyperthermia, gene therapy, photothermal and photodynamic therapies are also being explored. A wide variety of biomaterials including lipids, carbon-based materials, polymers, silica, bioactive glass, hydroxyapatite and metals are designed as delivery systems with the desired loading efficiency, release profile, and on-demand delivery. Among others, liposomal carriers have attracted a great deal of attention due to their capability to encapsulate both hydrophobic and hydrophilic drugs. Polymeric systems have high drug loading efficiency and stability and can even be tailored to achieve desired size and physiochemical properties. Carbon-based systems can also be seen as an upcoming class of therapeutics with great potential in treating different types of cancer. Inorganic materials like silica nanoparticles have high drug payload owing to their mesoporous structure. On the other hand, ceramic materials like bioactive glass and hydroxyapatite not only act as excellent delivery vectors but also participate in osteo-regeneration activity. These multifunctional biomaterials are also being investigated for their theranostic abilities to monitor cancer ablation. This review systematically discusses the vast landscape of biomaterials along with their challenges and respective opportunities for osteosarcoma therapy.

Surfactant Imprinting Hyperactivated Immobilized Lipase as Efficient Biocatalyst for Biodiesel Production from Waste Cooking Oil

Enzymatic production of biodiesel from waste cooking oil (WCO) could contribute to resolving the problems of energy demand and environment pollutions.In the present work, Burkholderia cepacia lipase (BCL) was activated by surfactant imprinting, and subsequently immobilized in magnetic cross-linked enzyme aggregates (mCLEAs) with hydroxyapatite coated magnetic nanoparticles (HAP-coated MNPs). The maximum hyperactivation of BCL mCLEAs was observed in the pretreatment of BCL with 0.1 mM Triton X-100. The optimized Triton-activated BCL mCLEAs was used as a highly active and robust biocatalyst for biodiesel production from WCO, exhibiting significant increase in biodiesel yield and tolerance to methanol. The results indicated that surfactant imprinting integrating mCLEAs could fix BCL in their active (open) form, experiencing a boost in activity and allowing biodiesel production performed in solvent without further addition of water. A maximal biodiesel yield of 98% was achieved under optimized conditions with molar ratio of methanol-to-WCO 7:1 in one-time addition in hexane at 40 °C. Therefore, the present study displays a versatile method for lipase immobilization and shows great practical latency in renewable biodiesel production.

Nanomaterials multifunctional behavior for enlightened cancer therapeutics

Cancer is an outrageous disease with uncontrolled differentiation, growth, and migration to the other parts of the body. It is the second-most common cause of death both in the U.S. and worldwide. Current conventional therapies, though much improved and with better prognosis, have several limitations. Chemotherapeutic agents, for instance, are cytotoxic to both tumor and healthy cells, and the non-specific distribution of drugs at tumor sites limits the dose administered. Nanotechnology, which evolved from the coalescence and union of varied scientific disciplines, is a novel science that has been the focus of much research. This technology is generating more effective cancer therapies to overcome biomedical and biophysical barriers against standard interventions in the body; its unique magnetic, electrical, and structural properties make it a promising tool. This article reviews endogenous- and exogenous-based stimulus-responsive drug delivery systems designed to overcome the limitations of conventional therapies. The article also summarizes the study of nanomaterials, including polymeric, gold, silver, magnetic, and quantum dot nanoparticles. Though an array of drug delivery systems has so far been proposed, there remain many challenges and concerns that should be addressed in order to fill the gaps in the field. Prominence is given to drug delivery systems that employ external- and internal-based stimuli and that are emerging as promising tools for cancer therapeutics in clinical settings.