Magnetic iron oxide nanoparticles (MIONPs) are particularly attractive in biosensor, antibacterial activity, targeted drug delivery, cell separation, magnetic resonance imaging tumor magnetic hyperthermia, and so on because of their particular properties including superparamagnetic behavior, low toxicity, biocompatibility, etc. Although many methods had been developed to produce MIONPs, some challenges such as severe agglomeration, serious oxidation, and irregular size are still faced in the synthesis of MIONPs. Thus, various strategies had been developed for the surface modification of MIONPs to improve the characteristics of them and obtain multifunctional MIONPs, which will widen the applicational scopes of them. Therefore, the processes, mechanisms, advances, advantages, and disadvantages of six main approaches for the synthesis of MIONPs; surface modification of MIONPs with inorganic materials, organic molecules, and polymer molecules; applications of MIONPs or modified MIONPs; the technical challenges of synthesizing MIONPs; and their limitations in biomedical applications were described in this review to provide the theoretical and technological guidance for their future applications.

Numerous studies have reported that amyloid-beta 42 (Aβ-42) protein is a high-profile risk factor associated with the onset and progression of Alzheimer’s disease (AD). Accumulation of extracellular senile plaques, synaptic degeneration, and intracellular neurofibrillary tangles were recorded as essential features that facilitate the onset of Aβ-42, resulting in AD. Hence, we attempted a new screening technique to discover potential inhibitors against Aβ-42 using an in silico deep neural network approach. We screened PubChem compounds library and found wgx-50 as a potential inhibitor of Aβ-42. Also, synergistic effects of wgx-50–gold nanoparticles (AuNPs) complex induced significant inhibition of Aβ-42, compared with those of wgx-50 alone. Further, molecular docking analysis, systems biology approach, and time course simulation confirmed that synergistic effects of wgx-50–AuNPs complex have potential application in the treatment for AD. Additionally, we proposed the biological circuit for AD induced by Aβ-42 that can be used to monitor the effect of drugs on AD.

G-protein-coupled receptor 142 (GPR142) belongs to rhodopsin family. GPR142 and GPR119, both Gq-coupled receptors, are expressed in pancreatic β cells of pancreas; their activation eventually leads to triggering of insulin secretion. In this paper, through a systems and synthetic biology approach, the effect of a common hit compound has been investigated in GPR142 and GPR119 pathways. This hit that has the potential to be developed as a lead for nanodrug was obtained through high-throughput virtual screening. The hit compound was further docked with nanoparticles (GOLD, SPION, and CeO2). The probable effect of this potential hit on insulin secretion in type 2 diabetes and its dynamic behavior was explored. Kinetic simulation was performed for cross-validation of its role in both the pathways. This study opens up a probable avenue in therapy of type 2 diabetes through regulation of GPR142 and GPR119 receptors. The biological circuit constructed may further have an application as a modulator to control the up- and downregulation of the biochemical pathway and can be implemented as sensors or nanochips for therapy.

Obtention of titanium (Ti)- and titanium dioxide (TiO2)–based nanocomposites is of great interest for biological nanomaterial applications, including for dental implants. Their mechanical properties can be improved by use of hydroxyapatite (HA) and chitosan through their biological anchorage with osseointegration and antibacterial activity. Electrochemical methods were chosen to obtain these composites in a quick and controllable way. In this work, electrochemical synthesis in one (alternated potential) or two steps (alternated or constant potential) was successfully applied. The single step (SS) obtained TiO2 + HA sample had different optical properties, as shown using ultraviolet–visible spectrometry, and the HA phase formation was proved using Raman spectroscopy. Thereby, SS_TiO2 + HA increased the corrosion resistance of titanium in artificial saliva medium, as shown by linear polarization and electrochemical impedance spectroscopy results. When using chitosan, the samples showed two corrosion interfaces, indicating its dissolution in human medium. These results indicate that the samples are excellent materials for dental implants.

In this study, Sr-incorporated nano-assembled hydroxyapatite structures (HASr) on 316L stainless steel bone plates were prepared by a biomimetic method induced by 10× simulated body fluid (SBF). First, HASr was coated on bone plates by the interaction of ions with 10× SBF containing different concentration of strontium ions. Then, silver coating is achieved as a second layer on bone plates. The cumulative release of strontium ions (Sr2+) and silver ions (Ag+) from multilayered HASr-Ag bone plates at the end of 15 days was in the range of 0.016–0.085 mM and 0.064–0.135 mM, respectively. The release mechanism for the bone plates was evaluated by several mathematical models that best fit the release data. The results showed that Sr2+ and Ag+ are released from multilayered bone plates by diffusion, whereas the release of Ag+ is not occurred by diffusion, instead the mechanism is dissolution, when silver is coated alone on bone plates.

Surface properties of titanium implants are key factors for rapid and stable bone tissue integration. So, in order to promote the osseointegration of implants, various surface treatments have been proposed. The objective of these surface treatments is to improve protein adsorption, cell adhesion and differentiation, and consequently, the tissue integration of titanium implants. In this paper, we propose to describe and compare the different strategies available in the literature to produce micro- and nanostructured surfaces on titanium, especially the recent results using electrochemical anodization. Anodization is a cost-effective process that produces nanostructures based on the electrolytic growth of columnar titanium oxide layers. By mastering the electrolyte composition and voltage, a regular array of pores with controlled diameters ranging from 15 to 200 nm are easily produced. Then we will present the latest results on the osteointegration of the surface composed anodized titania nanotubes.

As distinctive spontaneous polarization and far-infrared radiation characteristics, the natural mineral tourmaline (TM) has the regulatory effect on crystallization behavior, which possesses potential application in biomimetic mineralization and bone regeneration. In this study, polyurethane (PU) and gelatin (GE) membranes with different adding proportion of TM nanoparticles were prepared via electrospinning. Additionally, the effect of TM nanoparticles on the mineralization process of hydrophobic PU and hydrophilic GE was investigated by immersing the composite TM/PU and TM/GE electrospun membranes in the 10× simulated body fluid (10SBF) at 37 °C for varying periods of time. SEM images confirmed the well-dispersed TM nanoparticles in the PU and GE electrospun fibers. The mineralization deposition was characterized by the SEM, EDS, XRD, and FTIR, and it indicated that two types of calcium phosphate deposits with different Ca/P molar ratios were obtained when TM/PU membranes and TM/GE membranes were incubated in 10SBF. Honeycomb-like hydroxyapatite crystals nucleated and grew faster on TM/PU and TM/GE membranes than the pure PU and GE membranes, respectively. Furthermore, with the increase of the added TM nanoparticles in the composite membranes, more calcium phosphate crystals were precipitated. These results showed that the added TM nanoparticles were able to improve the mineralization of polymer fibrous membranes, which is potential for the composite bone scaffold.

The antibacterial hydrogels can be widely used in the biomedical area owing to their excellent properties. The main limitation of antibacterial hydrogels is their poor mechanical strength. In this study, the novel hydrogels were fabricated with a mixture of silk fibroin (SF), chitosan (CH), agarose (AG), and silver nanoparticles (SNPs) via facile reaction condition without inorganic substances. The mechanical property of these fabricated hydrogels can be modulated by the concentration of SF or AG. The rheological studies demonstrated enhanced elasticity of CH-doped hydrogels. Because of the presence of CH and Ag in hydrogels, the antimicrobial property against gram-positive and gram-negative bacteria was exhibited. Cytocompatibility test proved the very low toxic nature of the hydrogels. In addition, these composite hydrogels have a smaller porosity, higher swelling ratio, and good compatibility, indicating their great potential for biomedical application.

In this work, a multifunctional system was developed in which antibacterial and luminescent properties were inserted into the matrix of hydroxyapatite (HAp) and its efficiency as a support for an antineoplastic drug was evaluated, aiming its application in the treatment of osseous diseases. The precipitation method was used for the synthesis of HAp, EuCl3 was used for the incorporation of Eu3+ as imaging agents, silver nanoparticles (AgNPs) with antimicrobial function were used, and a model of drug, 5-fluorouracil (5FU) was used. The developed material is characterized by several techniques, where crystalline peaks attributed to HAp were identified in the X-ray diffractogram, whereas the luminescence spectrum of the material presented emissions attributed to the Eu3+ ion. The identification and the uniform distribution of AgNPs, 5FU, and Eu3+ were confirmed by mapping the sample using energy-dispersive spectroscopy. The measurements indicated that 82% (±2.8) of 5FU was incorporated into the HAp matrix, and a gradual and increasing release of it as a function of time was observed. Assays carried out for different bacteria confirmed the antimicrobial action of the samples and the efficiency of the drug inserted into the matrix. An in vitro assay showed the bioactivity of the material and its potential to bind to living osseous tissue.

Electrospun coaxial fibers are used to create core/sheath fiber structures to act as growth-promoting scaffolds for in vitro dorsal root ganglia (DRG) cell cultures. The core was a conducting polymer, poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS), and the sheath was poly-L-lactic acid (PLLA), which created coaxial fibers with a conductive core and an insulating sheath. SEM analysis confirmed the conductivity of the core and insulation of the sheath. Several coaxial spinneret designs were tested with the best results obtained by using various annular spinning needle combinations. Using a 22G/16G and 22G/17G combination, fibers with diameters of 6.1 ± 2.4 µm and 3.3 ± 0.9 µm were spun, respectively. The fibers showed a Young’s modulus and hardness of 0.16 ± 0.13 and 0.02 ± 0.01 GPa for the larger diameters, and 0.7 ± 0.4 and 0.03 ± 0.03 GPa for the smaller diameter fibers. In vitro test cultures showed the fibers successfully directed chick DRG axonal outgrowth with low biotoxicity.

The novelty of this study was to investigate for the first time in literature the influence of Bombyx mori silkworm cocoon’s age on the properties of silk fibroin-based materials, during all stages of cocoon processing to obtain the fibroin film. The study started with the premise that the cocoon age could cause modifications on fibroin properties during processing and, consequently, a possible interference on the characteristics of the final product. Characterizations were performed using batches of cocoons produced in different years, named C0 (fresh cocoons) and C6 (six-year-old cocoons). The influence of cocoon’s aging was observed on dialyzed dispersion regarding the molecular weight, particle size, and conformation. C6 films showed a more crystalline structure and higher thermal resistance than C0 films. The findings reported in this work are relevant for the reproducibility of fibroin-based materials, and the cocoon age is a key factor that should be considered in the preparation of fibroin-based materials.

One of the most promising nanoscale materials which fascinated researchers for the last few decades owing to its unique optoelectronics and physicochemical properties are carbon-based nanomaterials (CBNs). Various forms of CBNs have been developed such as single and multi-walled carbon nanotubes, graphene, fullerenes, nanodiamonds, and fluorescent carbon quantum dots (C-Dots) whereas each form is having its own exceptional properties owing to its dimensionalities and architectures. The advent of these unique classes of nanoscale materials opens up a spectrum of new opportunities and possibilities in employing these in emerging areas of biomedical. However, successful biomedical applications greatly rely on the likelihood of the comprehensive understanding of physicochemical interactions and biological responses of CBNs. Herein, we have tried to explore the ‘blood-CBNs’ interface by including the findings of recent studies. The role of surface modifications and functionalization in order to mitigate the adverse outcomes has also been incorporated.