Electrospun nanofibers as versatile platform in antimicrobial delivery: current state and perspectives

From nature to nanomedicine: bioengineered metallic nanoparticles bridge the gap for medical applications

The escalating global challenge of antimicrobial resistance demands innovative approaches. This review delves into the current status and future prospects of bioengineered metallic nanoparticles derived from natural sources as potent antimicrobial agents. The unique attributes of metallic nanoparticles and the abundance of natural resources have sparked a burgeoning field of research in combating microbial infections. A systematic review of the literature was conducted, encompassing a wide range of studies investigating the synthesis, characterization, and antimicrobial mechanisms of bioengineered metallic nanoparticles. Databases such as PubMed, Scopus, Web of Science, ScienceDirect, Springer, Taylor & Francis online and OpenAthen were extensively searched to compile a comprehensive overview of the topic. The synthesis methods, including green and sustainable approaches, were examined, as were the diverse biological sources used in nanoparticle fabrication. The amalgamation of metallic nanoparticles and natural products has yielded promising antimicrobial agents. Their multifaceted mechanisms, including membrane disruption, oxidative stress induction, and enzyme inhibition, render them effective against various pathogens, including drug-resistant strains. Moreover, the potential for targeted drug delivery systems using these nanoparticles has opened new avenues for personalized medicine. Bioengineered metallic nanoparticles derived from natural sources represent a dynamic frontier in the battle against microbial infections. The current status of research underscores their remarkable antimicrobial efficacy and multifaceted mechanisms of action. Future prospects are bright, with opportunities for scalability and cost-effectiveness through sustainable synthesis methods. However, addressing toxicity, regulatory hurdles, and environmental considerations remains crucial. In conclusion, this review highlights the evolving landscape of bioengineered metallic nanoparticles, offering valuable insights into their current status and their potential to revolutionize antimicrobial therapy in the future.

Evaluation of the wound healing efficacy of new antibacterial polymeric nanofiber based on polyethylene oxide coated with copper nanoparticles and defensin peptide: An in-vitro to in-vivo assessment

Objective

Today, designing nanofibers with antibacterial properties using electrospinning technology is one of the attractive approaches for wound healing.

Methods

& analysis: This study aims to fabricate a nanocomposite from polyethylene oxide (PEO) coated with copper nanoparticles (NPs) and defensin peptide with wound healing and antimicrobial properties in different ratios of CuNPs/defensin (2/0 mg), (1.5/0.5 mg), and (1/1 mg) in the fixed contain polymer (98 mg). Then, the nanofiber properties were investigated by SEM, tensile, DSC, and BET analysis. Also, the antibacterial properties against S. aureus and E. coli, antioxidant, and in-vivo wound healing effects and histological analysis of the designed nanocomposites were evaluated in rat models.

Results

Our SEM images showed that CuNPs and defensin were properly coated on the PEO surface. According to the tensile, DSC, and antibacterial analysis results, the most appropriate feature was related to CuNPs/defensin (1.5/0.5 mg), with maximum elasticity, heat resistance, and antibacterial activity. Furthermore, the designed nanocomposites showed the best performance as a wound closure agent by increasing dermis and epidermis volume density, stimulating fibroblast cells and collagen fiber production, and improving skin vessels.

Conclusion

According to our results, PEO nanofibers loaded with CuNPs and defensin have the best potential for wound healing, and they can be used as antibacterial materials in the textile, drug, and medical industries.

One-Step Synthesis of Silver Nanoparticles Embedded in Biobased Polyamide 56 Nanofibers with High Antibacterial Activity

Embedded silver nanoparticles (Ag NPs) within nanofibers represent a highly promising alternative to common antimicrobial materials, due to the combined effective biocidal properties of Ag NPs with the biocompatibility and environmental friendliness of biobased polymers. In this study, we presented a novel one-step route to fabricate biobased polyamide 56 (PA56) nanofibers embedded with uniform Ag NPs. The process involved mixing reactive silver ammonia with PA56 solutions and then using formic acid as a reducing agent. Continuous electrospinning resulted in solvent evaporation, yielding Ag NPs highly dispersed within PA56 nanonet fibrous structures (PA56/Ag). Characterization assays confirmed the successful impregnation of Ag NPs in PA56 nanofibers, with an average size of about 32.4 nm. PA56/Ag nanofibers also displayed suitable morphology, mechanical properties, and good biocompatibility in vitro. Moreover, their antimicrobial effectiveness was evaluated against Staphylococcus aureus and Escherichia coli. Collectively, the proposed PA56/Ag nanofibers possess desirable characteristics suitable for antimicrobial applications.

Effect of Curcumin-containing Nanofibrous Gelatin-hydroxyapatite Scaffold on Proliferation and Early Osteogenic Differentiation of Dental Pulp Stem Cells

BACKGROUND

In recent years, the electrospinning method has received attention because of its usage in producing a mimetic nanocomposite scaffold for tissue regeneration. Hydroxyapatite and gelatin are suitable materials for producing scaffolds, and curcumin has the osteogenesis induction effect.

AIMS

This study aimed to evaluate the toxicity and early osteogenic differentiation stimulation of nanofibrous gelatin-hydroxyapatite scaffold containing curcumin on dental pulp stem cells (DPSCs).

OBJECTIVE

The objective of the present investigation was the evaluation of the proliferative effect and primary osteogenic stimulation of DPSCs with a nanofibrous gelatin-hydroxyapatite scaffold containing curcumin. Hydroxyapatite and gelatin were used as suitable and biocompatible materials to make a scaffold suitable for stimulating osteogenesis. Curcumin was added to the scaffold as an osteogenic differentiation- enhancing agent.

METHODS

The effect of nano-scaffold on the proliferation of DPSCs was evaluated. The activity of alkaline phosphatase (ALP) as the early osteogenic marker was considered to assess primary osteogenesis stimulation in DPSCs.

RESULTS

The nanofibrous gelatin-hydroxyapatite scaffold containing curcumin significantly increased the proliferation and the ALP activity of DPSCs (P<0.05). The proliferative effect was insignificant in the first 2 days, but the scaffold increased cell proliferation by more than 40% in the fourth and sixth days. The prepared scaffold increased the activity of the ALP of DPSCs by 60% compared with the control after 14 days (p<0.05).

CONCLUSION

The produced nanofibrous gelatin-hydroxyapatite scaffold containing curcumin can be utilized as a potential candidate in tissue engineering and regeneration of bone and tooth.

FUTURE PROSPECTS

The prepared scaffold in the present study could be a beneficial biomaterial for tissue engineering and the regeneration of bone and tooth soon.

Preparation, Physicochemical Characterization, Antimicrobial Effects, Biocompatibility and Cytotoxicity of Co-Loaded Meropenem and Vancomycin in Mesoporous Silica Nanoparticles

Mesoporous silica nanoparticles (MSNPs) have been reported as an effective system to co-deliver a variety of different agents to enhance efficiency and improve biocompatibility. This study was aimed at the preparation, physicochemical characterization, antimicrobial effects, biocompatibility, and cytotoxicity of vancomycin and meropenem co-loaded in the mesoporous silica nanoparticles (Van/Mrp-MSNPs). The prepared nanoparticles were explored for their physicochemical features, antibacterial and antibiofilm effects, biocompatibility, and cytotoxicity. The minimum inhibitory concentrations (MICs) of the Van/Mrp-MSNPs (0.12-1 µg/mL) against Staphylococcus aureus isolates were observed to be lower than those of the same concentrations of vancomycin and meropenem. The minimum biofilm inhibitory concentration (MBIC) range of the Van/Mrp-MSNPs was 8-64 μg/mL, which was lower than the meropenem and vancomycin MBICs. The bacterial adherence was not significantly decreased upon exposure to levels lower than the MICs of the MSNPs and Van/Mrp-MSNPs. The viability of NIH/3T3 cells treated with serial concentrations of the MSNPs and Van/Mrp-MSNPs were 73-88% and 74-90%, respectively. The Van/Mrp-MSNPs displayed considerable inhibitory effects against MRSA, favorable biocompatibility, and low cytotoxicity. The Van/Mrp-MSNPs could be a potential system for the treatment of infections.

Drug cross-linking electrospun fiber for effective infected wound healing

The management of infected wounds is still an intractable challenge in clinic. Development of antibacterial wound dressing is of great practical significance for wound management. Herein, a natural-derived antibacterial drug, tannic acid (TA), was incorporated into the electrospun polyvinyl alcohol (PVA) fiber (TA/PVA fiber, 952 ± 40 nm in diameter). TA worked as a cross-linker via hydrogen bonding with PVA to improve the physicochemical properties of the fiber and to reach a sustained drug release (88% release of drug at 48 h). Improved mechanical property (0.8-1.2 MPa) and computational simulation validated the formation of the hydrogen bonds between TA and PVA. Moreover, the antibacterial and anti-inflammatory characteristics of TA laid the foundation for the application of TA/PVA fiber in repairing infected wounds. Meanwhile, in vitro studies proved the high hemocompatibility and cytocompatibility of TA/PVA fiber. Further in vivo animal investigation showed that the TA/PVA fiber promoted the repair of infected wound by inhibiting the bacterial growth, promoting granulation formation, and collagen matrix deposition, accelerating angiogenesis, and inducing M2 macrophage polarization within 14 days. All the data demonstrated that the TA cross-linked fiber would be a potent dressing for bacteria-infected wound healing.

Potential applications of medicinal herbs and phytochemicals in oral and dental health: Status quo and future perspectives

OBJECTIVE

Herbal therapies are utilized to treat a broad diversity of diseases all over the globe. Although no clinical studies have been conducted to demonstrate the antibacterial, antimicrobial, and antiplaque characteristics of these plants, this does not imply that they are ineffectual as periodontal treatments or anti-cariogenic drugs. However, there is a scarcity of research confirming their efficacy and worth.

SUBJECT

Herbs are utilized in dentistry as antimicrobial, antineoplastic, antiseptic, antioxidant, and analgesics agents as well as for the elimination of bad breath. In addition, the application of herbal agents in tissue engineering improved the regeneration of oral and dental tissues. This study reviews the application of medicinal herbs for the treatment of dental and oral diseases in different aspects.

METHODS

This article focuses on current developments in the use of medicinal herbs and phytochemicals in oral and dental health. An extensive literature review was conducted via an Internet database, mostly PubMed. The articles included full-text publications written in English without any restrictions on a date.

CONCLUSION

Plants have been suggested, as an alternate remedy for oral-dental problems, and this vocation needs long-term dependability. More research on herbal medicine potential as pharmaceutical sources and/or therapies is needed.

From Poly(glycerol itaconate) Gels to Novel Nonwoven Materials for Biomedical Applications

Electrospinning is a process that has attracted significant interest in recent years. It provides the opportunity to produce nanofibers that mimic the extracellular matrix. As a result, it is possible to use the nonwovens as scaffolds characterized by high cellular adhesion. This work focused on the synthesis of poly(glycerol itaconate) (PGItc) and preparation of nonwovens based on PGItc gels and polylactide. PGItc gels were synthesized by a reaction between itaconic anhydride and glycerol. The use of a mixture of PGItc and PLA allowed us to obtain a material with different properties than with stand-alone polymers. In this study, we present the influence of the chosen ratios of polymers and the OH/COOH ratio in the synthesized PGItc on the properties of the obtained materials. The addition of PGItc results in hydrophilization of the nonwovens' surface without disrupting the high porosity of the fibrous structure. Spectral and thermal analyzes are presented, along with SEM imagining. The preliminary cytotoxicity research showed that nonwovens were non-cytotoxic materials. It also helped to pre-determine the potential application of PGItc + PLA nonwovens as subcutaneous tissue fillers or drug delivery systems.

Fabrication and Characterization of Electrospun Chitosan/Polylactic Acid (CH/PLA) Nanofiber Scaffolds for Biomedical Application

The present study demonstrates a strategy for preparing porous composite fibrous materials with superior biocompatibility and antibacterial performance. The findings reveal that the incorporation of PEG into the spinning solutions significantly influences the fiber diameters, morphology, and porous area fraction. The addition of a hydrophilic homopolymer, PEG, into the Ch/PLA spinning solution enhances the hydrophilicity of the resulting materials. The hybrid fibrous materials, comprising Ch modified with PLA and PEG as a co-solvent, along with post-treatment to improve water stability, exhibit a slower rate of degradation (stable, moderate weight loss over 16 weeks) and reduced hydrophobicity (lower contact angle, reaching 21.95 ± 2.17°), rendering them promising for biomedical applications. The antibacterial activity of the membranes is evaluated against Staphylococcus aureus and Escherichia coli, with PEG-containing samples showing a twofold increase in bacterial reduction rate. In vitro cell culture studies demonstrated that PEG-containing materials promote uniform cell attachment, comparable to PEG-free nanofibers. The comprehensive evaluation of these novel materials, which exhibit improved physical, chemical, and biological properties, highlights their potential for biomedical applications in tissue engineering and regenerative medicine.

Nano-Catechin Gel as a Sustained Release Antimicrobial Agent against Clinically Isolated Porphyromonas gingivalis for Promising Treatment of Periodontal Diseases

During the last two decades, new drug delivery strategies have been invented that have been able to solve microbial resistance against antibiotics. The goal of the current report was to assess the antimicrobial effects of nano-catechin gels against clinically isolated Porphyromonas gingivalis, one of the main causes of periodontal disease. Catechin-loaded chitosan nanoparticles were prepared by adding a catechin solution to a chitosan solution. Then, the mean particle size and the mean surface charge (zeta potential) of the nanoparticles were detected through photon correlation spectroscopy and zeta sizer, respectively. Nano-catechin gels (1000, 500, 250, 125, 62.5, and 31.2 µg/mL) were prepared, and the antimicrobial assay was performed against clinically isolated Porphyromonas gingivalis (P. gingivalis). The clinically obtained P. gingivalis isolates were obtained from periodontitis patients (N = 15). The consequences are specified as descriptive indices. The normality of data was detected by the Shapiro-Wilk test. Then, to compare the data between groups (with a p value < 0.05 as the significance level), SPSS software (version 22) was used via a Mann-Whitney U test. The results showed a nanometer particle size range and a positive zeta potential for the prepared nanoparticles. All the concentrations (1000, 500, 250, 125, 62.5, and 31.2 µg/mL) of nano-catechin gels showed sustained release patterns and were non-toxic against dental pulp stem cells as well. There were no significant differences between the minimal inhibitory concentrations (MICs) for nano-catechin gel (test group) and Chlorhexidine (control group) against 15 isolates (p > 0.05). Then, two groups showed similar antimicrobial effects. The similar antimicrobial activity of catechin nanoparticles and Chlorhexidine, as a potent antimicrobial agents, against clinically isolated P. gingivalis showed that catechin nanoparticles can be used as a potent antimicrobial material for the treatment of periodontal diseases in the near future.

Wettability of Amino Acid-Functionalized PSMA Electrospun Fibers for the Modulated Release of Active Agents and Its Effect on Their Bioactivity

The ideal treatment for chronic wounds is based on the use of bioactive dressings capable of releasing active agents. However, the control of the rate at which these active agents are released is still a challenge. Bioactive polymeric fiber mats of poly(styrene-co-maleic anhydride) [PSMA] functionalized with amino acids of different hydropathic indices and L-glutamine, L-phenylalanine and L-tyrosine levels allowed obtaining derivatives of the copolymers named PSMA@Gln, PSMA@Phe and PSMA@Tyr, respectively, with the aim of modulating the wettability of the mats. The bioactive characteristics of mats were obtained by the incorporation of the active agents Calendula officinalis (Cal) and silver nanoparticles (AgNPs). A higher wettability for PSMA@Gln was observed, which is in accordance with the hydropathic index value of the amino acid. However, the release of AgNPs was higher for PSMA and more controlled for functionalized PSMA (PSMAf), while the release curves of Cal did not show behavior related to the wettability of the mats due to the apolar character of the active agent. Finally, the differences in the wettability of the mats also affected their bioactivity, which was evaluated in bacterial cultures of Staphylococcus aureus ATCC 25923 and methicillin-resistant Staphylococcus aureus ATCC 33592, an NIH/3T3 fibroblast cell line and red blood cells.

Antibacterial and biofilm-inhibitory effects of vancomycin-loaded mesoporous silica nanoparticles on methicillin-resistant staphylococcus aureus and gram-negative bacteria

The present study aimed to prepare and characterize vancomycin-loaded mesoporous silica nanoparticles (Van-MSNs) to detect inhibitory effects on the planktonic and biofilm forms of methicillin-resistant Staphylococcus aureus (MRSA) isolates, and study the biocompatibility and toxicity of Van-MSNs in vitro as well as antibacterial activity of Van-MSNs against Gram-negative bacteria. The inhibitory effects of Van-MSNs were investigated on MRSA using the determination of minimum inhibitory (MIC) and minimum biofilm-inhibitory concentrations (MBIC) as well as the effect on bacterial attachment. Biocompatibility was studied by examining the effect of Van-MSNs on the lysis and sedimentation rate of red blood cells (RBC). The interaction of Van-MSNs with human blood plasma was detected by the SDS-PAGE approach. The cytotoxic effect of the Van-MSNs on human bone marrow mesenchymal stem cells (hBM-MSCs) was evaluated by the MTT assay. The antibacterial effects of vancomycin and Van-MSNs on Gram-negative bacteria were also investigated using MIC determination using the broth microdilution method. Furthermore, bacteria outer membrane (OM) permeabilization was determined. Van-MSNs showed inhibitory effects on planktonic and biofilm forms of bacteria on all isolates at levels lower than MICs and MBICs of free vancomycin, but the antibiofilm effect of Van-MSNs was not significant. However, Van-MSNs did not affect bacterial attachment to surfaces. Van-loaded MSNs did not show a considerable effect on the lysis and sedimentation of RBC. A low interaction of Van-MSNs was detected with albumin (66.5 kDa). The hBM-MSCs viability in exposure to different levels of Van-MSNs was 91-100%. MICs of ≥ 128 µg/mL were observed for vancomycin against all Gram-negative bacteria. In contrast, Van-MSNs exhibited modest antibacterial activity inhibiting the tested Gram-negative bacterial strains, at concentrations of ≤ 16 µg/mL. Van-MSNs increased the OM permeability of bacteria that can increase the antimicrobial effect of vancomycin. According to our findings, Van-loaded MSNs have low cytotoxicity, desirable biocompatibility, and antibacterial effects and can be an option for the battle against planktonic MRSA.

Gelatin-hydroxyapatite Fibrous Nanocomposite for Regenerative Dentistry and bone Tissue Engineering

Aims:

This study aimed to prepare and physicochemically evaluate as well as assess the cytotoxicity and stimulation of early osteogenic differentiation of dental pulp stem cells of gelatin-hydroxyapatite (Gel-HA) fibrous nanocomposite scaffold.

Background:

Recently, the electrospinning approach in nanotechnology has been considered due to its application in the preparation of biomimetic nanofibers for tissue engineering.

Objective:

The main objective of this study was to evaluate Gel-HA fibrous nanocomposite for regenerative dentistry and bone tissue engineering material.

Methods:

The nano-scaffold was prepared via the electrospinning method. Then, the physicochemical properties (particle size, surface charge, morphology, hydrophilicity, specific surface area, crystalline state and the characterization of functional groups) and the proliferative effects of nano-scaffolds on dental pulp stem cells were assessed. The alkaline phosphatase activity was assessed for evaluation of early osteogenic differentiation of dental pulp stem cells.

Results:

The prepared nano-scaffolds had a negative surface charge (-30 mv±1.3), mono-dispersed nano-scale diameter (98 nm±1.2), crystalline state and fibrous uniform morphology without any bead (structural defects). The nanofibrous scaffold showed increased hydrophobicity compared to gelatin nanofibers. Based on Brunauer-Emmett-Teller analysis, the specific surface area, pore volume and pore diameter of Gel-HA nanofibers decreased compared to gelatin nanofibers. The Gel-HA nano-fibers showed the proliferative effect and increased the alkaline phosphatase activity of cells significantly (P<0.05).

Conclusion:

The prepared Gel-HA nanofibers can be considered potential candidates for application in bone tissue engineering and regenerative dentistry.

Other:

Gel-HA nanofibers could be a potential material for bone regeneration and regenerative dentistry in the near future.

Guided bone regeneration with extracellular matrix scaffold of small intestinal submucosa membrane

Guided bone regeneration (GBR) is a promising strategy for repairing bone defects using bioactive membranes. In this study, a new type of GBR membrane based on the small intestinal submucosa (SIS) was created, and its surface structure, cytological characteristics, and bone defect repair ability were compared with commonly used membranes. Our results show that compared to the Heal-all and Dentium membranes, the SIS membrane has an asymmetric structure that does not affect the proliferation of bone marrow mesenchymal stem cells (BMSCs). Instead, it increased their formation of calcium nodules and expression of bone morphogenetic protein-2 (BMP-2), alkaline phosphatase (ALP), runt-related transcription factor 2 (Runx2), and osteopontin (OPN). Six weeks after their insertion into a rat calvarial defect model, increased bone growth was observed in the SIS membrane group. Our results indicate that the SIS membrane has good biocompatibility and is more effective in promoting early bone formation than existing membranes. Given the wide range of source materials and simple preparation processes available, SIS membrane is a promising candidate for guided bone regeneration.

Coaxial fibers of poly(styrene-co-maleic anhydride)@poly(vinyl alcohol) for wound dressing applications: Dual and sustained delivery of bioactive agents promoting fibroblast proliferation with reduced cell adherence

The prevalence of chronic and acute wounds, as well as the complexity of their treatment represent a great challenge for health systems around the world. In this context, the development of bioactive wound dressings that release active agents to prevent infections and promote wound healing, appears as the most promising solution. In this work, we develop an antibacterial and biocompatible wound dressing material made from coaxial electrospun fibers of poly(styrene-co-maleic anhydride) and poly(vinyl alcohol) (PSMA@PVA). The coaxial configuration of the fibers consists of a shell of poly (styrene-co-maleic anhydride) containing a variable concentration of silver nanoparticles (AgNPs) 0.1-0.6 wt% as antibacterial agent, and a core of PVA containing 1 wt% allantoin as healing agent. The fibers present diameters between 0.72 and 1.7 µm. The release of Ag⁺ in a physiological medium was studied for 72 h, observing a burst release during the first 14 h and then a sustained and controlled release during the remaining 58 h. Allantoin release curves showed significant release only after 14 h. The meshes showed an antibacterial activity against Pseudomonas aeruginosa and Bacillus subtilis that correlates with the amount of AgNPs incorporated and the release rate of Ag⁺. Indeed, meshes containing 0.3 and 0.6 wt% of AgNPs showed a 99.99% inhibition against both bacteria. The adherence and cell viability of the meshes were evaluated in mouse embryonic fibroblasts NIH/3T3, observing a significant increase in cell viability after 72 h of incubation accompanied by a reduced adhesion of fibroblasts that decreased in the presence of the active agents. These results show that the material prepared here is capable of significantly promoting fibroblast cell proliferation but without strong adherence, which makes it an ideal material for wound dressings with non-adherent characteristics and with potential for wound healing.

Multifunctional Nanofibrous Dressing with Antimicrobial and Anti-Inflammatory Properties Prepared by Needle-Free Electrospinning

An active wound dressing should address the main goals in wound treatment, which are improved wound healing and reduced infection rates. We developed novel multifunctional nanofibrous wound dressings with three active ingredients: chloramphenicol (CAM), beta-glucan (βG) and chitosan (CHI), of which βG and CHI are active nanofiber-forming biopolymers isolated from the cell walls of Saccharomyces cerevisiae and from shrimp shells, respectively. To evaluate the effect of each active ingredient on the nanofibers' morphological features and bioactivity, nanofibers with both βG and CHI, only βG, only CHI and only copolymers, polyethylene oxide (PEO) and hydroxypropylmethylcellulose (HPMC) were fabricated. All four nanofiber formulations were also prepared with 1% CAM. The needle-free NanospiderTM technique allowed for the successful production of defect-free nanofibers containing all three active ingredients. The CAM-containing nanofibers had a burst CAM-release and a high absorption capacity. Nanofibers with all active ingredients (βG, CHI and CAM) showed a concentration-dependent anti-inflammatory activity, while maintaining the antimicrobial activity of CAM. The promising anti-inflammatory properties, together with the high absorption capacity and antimicrobial effect, make these multifunctional nanofibers promising as dressings in local treatment of infected and exuding wounds, such as burn wounds.

8-Hydroxyquinoline-5-Sulfonic Acid-Containing Poly(Vinyl Alcohol)/Chitosan Electrospun Materials and Their Cu2+ and Fe3+ Complexes: Preparation, Antibacterial, Antifungal and Antitumor Activities

Novel poly(vinyl alcohol) (PVA)/chitosan (Ch)-based fibrous materials containing an ionizable model drug, 8-hydroxyquinoline-5-sulfonic acid (SQ), were successfully fabricated by electrospinning. Complexes between the components of the crosslinked PVA/Ch/SQ mats and Cu2+ and Fe3+ ions were formed. The coordination of these ions in the mats was examined by electron paramagnetic resonance spectroscopy (EPR). The microbiological screening against S. aureus and C. albicans revealed that both the incorporation of SQ in the mats and the complexation with Cu2+ and Fe3+ imparted to these materials antibacterial and antifungal activities. Moreover, the SQ-containing mats and their complexes displayed good cytotoxicity against human cervical HeLa tumor cells. The most prominent was the cytotoxicity of the Cu2+ complex of the mats. The combined antibacterial, antifungal and in vitro antitumor activities render these novel materials promising candidates for wound dressing applications and for application in the local treatment of cervical tumors.

Electrospinning for drug delivery applications: A review

Drug delivery devices are promising tools in the pharmaceutical field, as they are able to maximize the therapeutic effects of the delivered drug while minimizing the undesired side effects. In the past years, electrospun nanofibers attracted rising attention due to their unique features, like biocompatibility and broad flexibility. Incorporation of active principles in nanofibrous meshes proved to be an efficient method for in situ delivery of a wide range of drugs, expanding the possibility and applicability of those devices. In this review, the principle of electrospinning and different fields of applications are treated to give an overview of the recent literature, underlining the easy tuning and endless combination of this technique, that in the future could be the new frontier of personalized medicine.

Application of Advanced Nanomaterials for Kidney Failure Treatment and Regeneration

The implementation of nanomedicine not only provides enhanced drug solubility and reduced off-target adverse effects, but also offers novel theranostic approaches in clinical practice. The increasing number of studies on the application of nanomaterials in kidney therapies has provided hope in a more efficient strategy for the treatment of renal diseases. The combination of biotechnology, material science and nanotechnology has rapidly gained momentum in the realm of therapeutic medicine. The establishment of the bedrock of this emerging field has been initiated and an exponential progress is observed which might significantly improve the quality of human life. In this context, several approaches based on nanomaterials have been applied in the treatment and regeneration of renal tissue. The presented review article in detail describes novel strategies for renal failure treatment with the use of various nanomaterials (including carbon nanotubes, nanofibrous membranes), mesenchymal stem cells-derived nanovesicles, and nanomaterial-based adsorbents and membranes that are used in wearable blood purification systems and synthetic kidneys.

Antimicrobial and antibiofilm activities of meropenem loaded-mesoporous silica nanoparticles against carbapenem-resistant Pseudomonas aeruginosa

The aims of the present study were the determination of antimicrobial and antibiofilm effects of meropenem-loaded mesoporous silica nanoparticles (MSNs) on carbapenem resistant Pseudomonas aeruginosa (P. aeruginosa) and cytotoxicity properties in vitro. The meropenem-loaded MSNs had shown antibacterial and biofilm inhibitory activities on all isolates at different levels lower than MICs and BICs of meropenem. The viability of HC-04 cells treated with serial concentrations as MICs and BICs of meropenem-loaded MSNs was 92-100%. According to the obtained results, meropenem-loaded MSNs display the significant antibacterial and antibiofilm effects against carbapenem resistant and biofilm forming P. aeruginosa and low cell toxicity in vitro. Then, the prepared system can be an appropriate option for the delivery of carbapenem for further evaluation in vivo assays.

Current approaches and future prospects of nanofibers: a special focus on antimicrobial drug delivery

Antibacterial nanofibers have a great potential for effective treatment of infections. They act as drug reservoir systems that release higher quantities of antibacterial agents/drug in a controlled manner at infection sites and prevent drug resistance, while concomitantly decreasing the systemic toxicity. With this drug delivery system, it is also possible to achieve multiple drug entrapment and also simultaneous or sequential release kinetics at the site of action. Therefore, advances in antibacterial nanofibers as drug delivery systems were overviewed within this article. Recently published data on antibacterial drug delivery was also summarised to provide a view of the current state of art in this field. Although antibacterial use seems to be limited and one can ask that 'what is left to be discovered?'; recent update literatures in this field highlighted the use of nanofibers from very different perspectives. We believe that readers will be benefiting this review for enlightening of novel ideas.

Nanofibrous asymmetric collagen/curcumin membrane containing aspirin-loaded PLGA nanoparticles for guided bone regeneration

The goal of the current study was to develop an asymmetric guided bone regeneration (GBR) membrane benefiting from curcumin and aspirin. The membrane was prepared using electrospinning technique and then was physic-chemically characterized by the conventional methods. The release profile of aspirin from the prepared membrane was also measured by ultraviolet spectrophotometry. Also, the antibacterial activities of the membrane was evaluated. We also assessed the in vitro effects of the prepared membrane on the biocompatibility and osteogenic differentiation of dental pulp stem cells (DPSCs), and evaluated in vivo bone regeneration using the prepared membrane in the defects created in both sides of the dog’s jaw by histology. The results from the characterization specified that the membrane was successfully prepared with monodispersed nanosized fibers, uniform network shaped morphology, negative surface charge and sustained release platform for aspirin. The membrane also showed antimicrobial effects against all tested bacteria. The presence of curcumin and aspirin in the asymmetric membrane enhanced osteogenic potential at both transcriptional and translational levels. The results of the animal test showed that the test area was completely filled with new bone after just 28 days, while the commercial membrane area remained empty. There was also a soft tissue layer above the new bone area in the test side. We suggested that the prepared membrane in this work could be used as a GBR membrane to keep soft tissue from occupying bone defects in GBR surgeries. Besides, the surgeries can be benefited from antibacterial activities and bone healing effects of this novel GBR membrane while, simultaneously, promoting bone regeneration.

Therapeutic benefits of rutin and its nanoformulations

BACKGROUND

Rutin as a natural flavonoid compound has revealed an extensive range of therapeutic potentials.

PURPOSE

The current paper is focused on the numerous studies on rutin nanoformulations regarding its broad spectrum of therapeutic potentials.

STUDY AND METHODS

A review was conducted in electronic databases (PubMed) to identify relevant published literature in English. No restrictions on publication date were imposed.

RESULTS

The literature search provided 7,078 results for rutin. Among them, 25 papers were related to the potential biological activities of rutin nanoformulations. Polymeric nanoparticles were the most studied nanoformulations for rutin (14 titles) and lipid nanoparticles (5 titles) were in second place. The reviewed literature showed that rutin has been used as an antimicrobial, antifungal, and anti-allergic agent. Improving the bioavailability of rutin using novel drug-delivery methods will help the investigators to use its useful effects in the treatment of various chronic human diseases.

CONCLUSION

It can be concluded that the preparation of rutin nanomaterials for the various therapeutic objects confirmed the enhanced aqueous solubility as well as enhanced efficacy compared to conventional delivery of rutin. However, more investigations should be conducted to confirm the improved bioavailability of the rutin nanoformulations.

Nanomaterials in Dentistry: State of the Art and Future Challenges

Nanomaterials are commonly considered as those materials in which the shape and molecular composition at a nanometer scale can be controlled. Subsequently, they present extraordinary properties that are being useful for the development of new and improved applications in many fields, including medicine. In dentistry, several research efforts are being conducted, especially during the last decade, for the improvement of the properties of materials used in dentistry. The objective of the present article is to offer the audience a complete and comprehensive review of the main applications that have been developed in dentistry, by the use of these materials, during the last two decades. It was shown how these materials are improving the treatments in mainly all the important areas of dentistry, such as endodontics, periodontics, implants, tissue engineering and restorative dentistry. The scope of the present review is, subsequently, to revise the main applications regarding nano-shaped materials in dentistry, including nanorods, nanofibers, nanotubes, nanospheres/nanoparticles, and zeolites and other orders porous materials. The results of the bibliographic analysis show that the most explored nanomaterials in dentistry are graphene and carbon nanotubes, and their derivatives. A detailed analysis and a comparative study of their applications show that, although they are quite similar, graphene-based materials seem to be more promising for most of the applications of interest in dentistry. The bibliographic study also demonstrated the potential of zeolite-based materials, although the low number of studies on their applications shows that they have not been totally explored, as well as other porous nanomaterials that have found important applications in medicine, such as metal organic frameworks, have not been explored. Subsequently, it is expected that the research effort will concentrate on graphene and zeolite-based materials in the coming years. Thus, the present review paper presents a detailed bibliographic study, with more than 200 references, in order to briefly describe the main achievements that have been described in dentistry using nanomaterials, compare and analyze them in a critical way, with the aim of predicting the future challenges.

Electrospun Nano-Fibers for Biomedical and Tissue Engineering Applications: A Comprehensive Review

Pharmaceutical nano-fibers have attracted widespread attention from researchers for reasons such as adaptability of the electro-spinning process and ease of production. As a flexible method for fabricating nano-fibers, electro-spinning is extensively used. An electro-spinning unit is composed of a pump or syringe, a high voltage current supplier, a metal plate collector and a spinneret. Optimization of the attained nano-fibers is undertaken through manipulation of the variables of the process and formulation, including concentration, viscosity, molecular mass, and physical phenomenon, as well as the environmental parameters including temperature and humidity. The nano-fibers achieved by electro-spinning can be utilized for drug loading. The mixing of two or more medicines can be performed via electro-spinning. Facilitation or inhibition of the burst release of a drug can be achieved by the use of the electro-spinning approach. This potential is anticipated to facilitate progression in applications of drug release modification and tissue engineering (TE). The present review aims to focus on electro-spinning, optimization parameters, pharmacological applications, biological characteristics, and in vivo analyses of the electro-spun nano-fibers. Furthermore, current developments and upcoming investigation directions are outlined for the advancement of electro-spun nano-fibers for TE. Moreover, the possible applications, complications and future developments of these nano-fibers are summarized in detail.

Anti-microbial activity of curcumin nanoformulations: New trends and future perspectives

Curcumin has been used in numerous anti-microbial research because of its low side effects and extensive traditional applications. Despite having a wide range of effects, the intrinsic physicochemical characteristics such as low bioavailability, poor water solubility, photodegradation, chemical instability, short half-life and fast metabolism of curcumin derivatives limit their pharmaceutical importance. To overcome these drawbacks and improve the therapeutic ability of curcuminoids, novel approaches have been attempted recently. Nanoparticulate drug delivery systems can increase the efficiency of curcumin in several diseases, especially infectious diseases. These innovative strategies include polymeric nanoparticles, hydrogels, nanoemulsion, nanocomposite, nanofibers, liposome, nanostructured lipid carriers (NLCs), polymeric micelles, quantum dots, polymeric blend films and nanomaterial-based combination of curcumin with other anti-bacterial agents. Integration of curcumin in these delivery systems has displayed to improve their solubility, bioavailability, transmembrane permeability, prolong plasma half-life, long-term stability, target-specific delivery and upgraded the therapeutic effects. In this review paper, a range of in vitro and in vivo studies have been critically discussed to explore the therapeutic viability and pharmaceutical significance of the nano-formulated delivery systems to elevate the anti-bacterial activities of curcumin and its derivatives.

One-step preparation of ibuprofen fast- and sustained-release formulation by electrospinning with improved efficacy and reduced side effect

In this study, we developed a one-step method to prepare ibuprofen fast- and sustained-release complex preparation. It was based on a double jets electrospinning process. Ibuprofen, a poorly water-soluble drug, was electrospun into fibers with polyvinyl pyrrolidone and hydroxypropyl methyl cellulose by two jets, respectively. The complex preparation had an enough initial dose come from fast-release part and a maintenance dose come from sustained-release part. Through the study of X-ray diffraction, differential scanning colorimetry (DSC), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM), it was confirmed that ibuprofen was highly dispersed in nanofibers (NFs) in amorphous state. Because one line of NFs was very thin and could only extend along two directions, it was difficult for ibuprofen to transform from amorphous to crystal in this kind of approximate one-dimensional structure. Additionally, it was confirmed by animal experiment that the complex preparation also had a benefit to reduce gastric irritation that usually caused by traditional oral ibuprofen preparation. Therefore, the method developed in this study was a convenient and good-quality approach for ibuprofen pain-alleviating preparation.