This study introduces a novel, sustainable method for synthesizing sub-5 nm palladium nanoparticles (PdNPs) and covalently binding them to chitosan nanofibers (CHITs) using fully oxidized dialdehyde cellulose (DAC). Notably, the DAC acts not only as a reducing and stabilizing agent for PdNPs, but also as a linker for their rapid and spontaneous covalent attachment to CHITs via Schiff base chemistry. This unique approach yields PdNPs with a narrow size distribution (4.7 ± 0.4 nm) and enables the preparation of a stable nanofibrous composite with excellent catalytic efficiency for 4-nitrophenol reduction (TOFPdNPs = 75.2 min-1, kPdNPs = 1.34 min-1; TOFPdNPs-CHIT = 1.18 min-1). The composite's high reusability, attributed to strong covalent binding, marks a significant improvement over traditional PdNPs composites that rely on weak interactions. This is demonstrated on a model of a catalytic device, reflecting industrial applications.

• Klíčová slova
• Chitosan nanofibers, Dialdehyde cellulose, Nanocomposite catalyst, Palladium nanoparticles,
• MeSH
• celulosa * chemie   analogy a deriváty   MeSH
• chitosan * chemie   MeSH
• katalýza MeSH
• kovové nanočástice * chemie   MeSH
• nanovlákna * chemie   ultrastruktura   MeSH
• nitrofenoly chemie   MeSH
• oxidace-redukce MeSH
• palladium * chemie   MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• 2,3-dialdehydocellulose MeSH Prohlížeč
• 4-nitrophenol MeSH Prohlížeč
• celulosa * MeSH
• chitosan * MeSH
• nitrofenoly MeSH
• palladium * MeSH

Herein, we report the fabrication and characterization of novel polycaprolactone (PCL)-based nanofibers functionalized with bare (ligand-free) titanium nitride (TiN) nanoparticles (NPs) for tissue engineering applications. Nanofibers were prepared by a newly developed protocol based on the electrospinning of PCL solutions together with TiN NPs synthesized by femtosecond laser ablation in acetone. The generated hybrid nanofibers were characterised using spectroscopy, microscopy, and thermal analysis techniques. As shown by scanning electron microscopy measurements, the fabricated electrospun nanofibers had uniform morphology, while their diameter varied between 0.403 ± 0.230 µm and 1.1 ± 0.15 µm by optimising electrospinning solutions and parameters. Thermal analysis measurements demonstrated that the inclusion of TiN NPs in nanofibers led to slight variation in mass degradation initiation and phase change behaviour (Tm). In vitro viability tests using the incubation of 3T3 fibroblast cells in a nanofiber-based matrix did not reveal any adverse effects, confirming the biocompatibility of hybrid nanofiber structures. The generated hybrid nanofibers functionalized with plasmonic TiN NPs are promising for the development of smart scaffold for tissue engineering platforms and open up new avenues for theranostic applications.

• Klíčová slova
• TiN nanoparticles, biocompatibility, electrospinning, nanofibers, polycaprolactone (PCL), pulsed laser ablation in liquids, scaffold for tissue engineering, theranostics,
• Publikační typ
• časopisecké články MeSH

In this study, we have developed a combined approach to accelerate the proliferation of mesenchymal stem cells (MSCs) in vitro, using a new nanofibrous scaffold made by needleless electrospinning from a mixture of poly-ε-caprolactone and magnetic particles. The biological characteristics of porcine MSCs were investigated while cultured in vitro on composite scaffold enriched with magnetic nanoparticles. Our data indicate that due to the synergic effect of the poly-ε-caprolactone nanofibers and magnetic particles, cellular adhesion and proliferation of MSCs is enhanced and osteogenic differentiation is supported. The cellular and physical attributes make this new scaffold very promising for the acceleration of efficient MSC proliferation and regeneration of hard tissues.

• Klíčová slova
• magnetic particles, mesenchymal stem cells, nanofibers, tissue engineering,
• MeSH
• biokompatibilní materiály chemie   farmakologie   MeSH
• buněčná adheze účinky léků   MeSH
• buněčná diferenciace účinky léků   MeSH
• kapronáty chemie   farmakologie   MeSH
• laktony chemie   farmakologie   MeSH
• magnetické nanočástice chemie   MeSH
• mezenchymální kmenové buňky cytologie   účinky léků   MeSH
• nanovlákna chemie   MeSH
• polyestery farmakologie   MeSH
• prasata MeSH
• proliferace buněk účinky léků   MeSH
• tkáňové inženýrství MeSH
• tkáňové podpůrné struktury chemie   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• biokompatibilní materiály MeSH
• caprolactone MeSH Prohlížeč
• kapronáty MeSH
• laktony MeSH
• magnetické nanočástice MeSH
• polyestery MeSH

Polysaccharides are often utilized as reducing and stabilizing agents and as support in the synthesis of gold nanoparticles (AuNPs). However, using approaches like spin coating or dip coating, AuNPs are generally bound to the support only by weak interactions, which can lead to decreased stability of the composite. Here, a two-stage approach for the preparation of composites with covalently anchored AuNPs is proposed. First, 5 nm AuNPs with high catalytic activity for the reduction of 4-nitrophenol (TOF = 15.8 min-1) were synthesized and stabilized using fully oxidized and solubilized 2,3-dialdehyde cellulose (DAC). Next, the carbonyl groups in the shell of prepared nanoparticles were used to tether AuNPs to chitosan nanofibers with quantitative efficacy in a process that we termed "affinity anchoring". Schiff bases formed during this process were subsequently reduced to secondary amines by borohydride, which greatly improved the stability of the composite in the broad pH range from 3 to 9. The catalytic efficacy of the resulting composite is demonstrated using a model catalytic device, showing high stability, fast conversion rates, and direct reusability.

• Klíčová slova
• Catalysis, Chitosan, Dialdehyde cellulose, Electrospinning, Gold nanoparticles, Nanofibers,
• Publikační typ
• časopisecké články MeSH

Nanofibers are well known as a beneficial type of structure for tissue engineering. As a result of the high acquisition cost of the natural polymers and their environmentally problematic treatment (toxic dissolution agents), artificial polymers seem to be the better choice for medical use. In the present study, polycaprolactone nano-sized fibrous structures were prepared by the electrospinning method. The impact of material morphology (random or parallelly oriented fibers versus continuous layer) and the presence of a fraction of hydroxyapatite nanoparticles on cell proliferation was tested. In addition, the effect of improving the material wettability by a low temperature argon discharge plasma treatment was evaluated, too. We have shown that both hydroxyapatite particles as well as plasma surface treatment are beneficial for the cell proliferation. The significant impact of both influences was evident during the first 48 h of the test: the hydroxyapatite particles in polycaprolactone fibers accelerated the proliferation by 10% compared to the control, and the plasma-treated ones enhanced proliferation by 30%.

• Klíčová slova
• atmospheric pressure argon plasma, electrospinning, hydroxyapatite, nanofibers, polycaprolactone, tissue engineering,
• Publikační typ
• časopisecké články MeSH

The aim of this study was to develop a novel amikacin (AMI) delivery system with prolonged release based on composite electrospun nanofibers of PLA supplemented with AMI-loaded Si nanoparticles of different morphology. The resultant materials were characterized in terms of their physical properties (scanning electron microscopy, Brunauer-Emmett-Teller analysis, thermogravimetric analysis, water contact angle). High-Performance Liquid Chromatography was used to determine the AMI content in the liquid fractions obtained from the release study. The results show that nanofibers of fumed silica exhibited an aggregated, highly porous structure, whereas nanofibers of mesoporous silica had a spherical morphology. Both silica nanoparticles had a significant effect on the hydrophilic properties of PLA nanofiber surfaces. The liquid fractions were investigated to gauge the encapsulation efficiency (EE) and loading efficiency (LE) of AMI, demonstrating 66% EE and 52% LE for nanofibers of fumed silica compared to nanofibers of mesoporous silica nanoparticles (52% EE and 12.7% LE). The antibacterial activity of the AMI-loaded nanofibers was determined by the Kirby-Bauer Method. These results demonstrated that the PLA-based silica nanofibers effectively enhanced the antibacterial properties against the Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, and Klebsiella pneumoniae.

• Klíčová slova
• electrospinning, nanofibers, silica nanoparticles,
• Publikační typ
• časopisecké články MeSH

A natural polymer of carboxymethyl starch (CMS) was used in combination with the inorganic mineral of β-Tricalcium Phosphate (β-TCP) and Poly l-lactide (PLLA) to prepare composite nanofibers with the potential to be used as a biomedical membrane. β-TCP contents varied in the range of 0.25% to 1% in the composition of PLLA and CMS. A mixed composition of these organic and inorganic materials was electro-spun to produce composite nanofibers. Morphological investigation indicated that smooth and uniform nanofibers could be produced via this technique. The average of the nanofiber diameters was slightly increased from 190 to 265 nm with the β-TCP content but some agglomeration of particles began to impede in the fiber at a higher content of β-TCP. It was observed that the fibers were damaged at a higher content of β-TCP nanoparticles. With the presence of higher β-TCP, the wettability of the PLLA was also improved, as indicated by the water contact angle measurement from 127.3° to 118°. The crystallization in the composite decreased, as shown in the changes in glass transition (Tg) and melting temperature (Tm) by differential scanning calorimeter (DSC) and X-ray diffraction analysis. Increases in β-TCP contributed to weaker mechanical strength, from 8.5 to 5.7 MPa, due to imperfect fiber structure.

• Klíčová slova
• carboxymethyl starch (CMS), electrospinning, nanofibers, poly l-lactide (PLLA), β-tricalcium phosphate (β-TCP),
• Publikační typ
• časopisecké články MeSH

This study investigates the impact of hydroxyapatite (HA) nanoparticles (NPs) on the cellular responses of poly(L-lactide-co-ε-caprolactone) (PLCL) scaffolds in bone tissue engineering applications. Three types of PLCL scaffolds were fabricated, varying in HANPs content. Saos-2 osteoblast-like cells (OBs) and THP-1-derived osteoclast-like cells (OCs) were co-cultured on the scaffolds, and cell proliferation was assessed using the MTS assay. The amount of double-stranded DNA (dsDNA) was quantified to evaluate cell proliferation. Expression levels of OBs and OCs markers were analyzed via quantitative polymerase chain reaction (qPCR) and the production of Collagen type I was visualized using confocal microscopy. Additionally, enzymatic activity of alkaline phosphatase (ALP) and tartrate-resistant acid phosphatase (TRAP or ACP5) was measured to assess OB and OC function, respectively. Interestingly, despite the scaffold's structured character supporting the growth of the Saos-2 OBs and THP-1-derived OCs coculture, the incorporation of HANPs did not significantly enhance cellular responses compared to scaffolds without HANPs, except for collagen type I production. These findings suggest the need for further investigation into the potential benefits of HANPs in bone tissue engineering applications. Nevertheless, our study contributes valuable insights into optimizing biomaterial design for bone tissue regeneration, with implications for drug screening and material testing protocols.

• Klíčová slova
• PLCL, bone regeneration, hydroxyapatite, osteoblasts, osteoclasts, scaffold, tissue engineering,
• MeSH
• buněčné linie MeSH
• hydroxyapatit * chemie   MeSH
• kokultivační techniky MeSH
• lidé MeSH
• nanočástice * chemie   MeSH
• nanovlákna * chemie   MeSH
• osteoblasty cytologie   metabolismus   účinky léků   MeSH
• osteogeneze MeSH
• osteoklasty cytologie   metabolismus   účinky léků   MeSH
• polyestery * chemie   MeSH
• proliferace buněk účinky léků   MeSH
• regenerace kostí * účinky léků   MeSH
• THP-1 buňky MeSH
• tkáňové inženýrství metody   MeSH
• tkáňové podpůrné struktury chemie   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• hydroxyapatit * MeSH
• poly(lactic acid-co-epsilon-caprolactone) MeSH Prohlížeč
• polyestery * MeSH

The creation of an antibacterial material with triggerable properties enables us to avoid the overuse or misuse of antibacterial substances and, thus, prevent the emergence of resistant bacterial strains. As a potential light-activated antibacterial material, polymethylmethacrylate (PMMA) nanofibers doped with silver nanoparticles (AgNPs) and meso-tetraphenylporphyrin (TPP) were prepared by electrospinning. TPP was chosen as an effectively reactive oxygen species (ROS) producer. Antibacterial tests on Staphylococcus epidermidis (S. epidermidis) and Enterococcus faecalis (E. faecalis) showed the excellent light-triggerable antibacterial activity of the doped materials. Upon light irradiation at the wavelength corresponding to the TPP absorption peak (405nm), antibacterial activity dramatically increased, mostly due to the release of AgNPs from the polymer matrix. Furthermore, under prolonged light irradiation, the AgNPs/TPP/PMMA nanofibers, displayed enhanced longevity and photothermal stability. Thus, our results suggest that the proposed material is a promising option for the photodynamic inactivation of bacteria.

• Klíčová slova
• Antibacterial, Light-activated, Polymethylmethacrylate, Silver nanoparticle, Triggerable release,
• MeSH
• antibakteriální látky chemie   MeSH
• Enterococcus faecalis růst a vývoj   MeSH
• kovové nanočástice chemie   ultrastruktura   MeSH
• nanovlákna chemie   ultrastruktura   MeSH
• polymethylmethakrylát chemie   MeSH
• Staphylococcus epidermidis růst a vývoj   MeSH
• stříbro chemie   MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• antibakteriální látky MeSH
• polymethylmethakrylát MeSH
• stříbro MeSH

Electrospun hybrid nanofibers, based on functional agents immobilized in polymeric matrix, possess a unique combination of collective properties. These are beneficial for a wide range of applications, which include theranostics, filtration, catalysis, and tissue engineering, among others. The combination of functional agents in a nanofiber matrix offer accessibility to multifunctional nanocompartments with significantly improved mechanical, electrical, and chemical properties, along with better biocompatibility and biodegradability. This review summarizes recent work performed for the fabrication, characterization, and optimization of different hybrid nanofibers containing varieties of functional agents, such as laser ablated inorganic nanoparticles (NPs), which include, for instance, gold nanoparticles (Au NPs) and titanium nitride nanoparticles (TiNPs), perovskites, drugs, growth factors, and smart, inorganic polymers. Biocompatible and biodegradable polymers such as chitosan, cellulose, and polycaprolactone are very promising macromolecules as a nanofiber matrix for immobilizing such functional agents. The assimilation of such polymeric matrices with functional agents that possess wide varieties of characteristics require a modified approach towards electrospinning techniques such as coelectrospinning and template spinning. Additional focus within this review is devoted to the state of the art for the implementations of these approaches as viable options for the achievement of multifunctional hybrid nanofibers. Finally, recent advances and challenges, in particular, mass fabrication and prospects of hybrid nanofibers for tissue engineering and biomedical applications have been summarized.

• Klíčová slova
• bone regeneration, drug delivery, electrospinning, functional agents, hybrid nanofibers, nanomedicine, nanoparticles, tissue engineering,
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH