Recently, more and more efforts are directed towards developing new imaging and drug-delivery options based on various nanoparticles, exploiting their unique properties. Here, ultra-small gold nanoparticles functionalized with widely used polyethylene glycol and its amine-terminated form were tested in respect of their potential interactions with human immune cells (cell line and primary cells). The results showed that differently terminated ultrasmall gold nanoparticles represent an interesting theranostic platform as they are harmless to immune cells (not inducing cytotoxicity and severe immune response) and on the other hand, they can serve as imaging and/or drug delivery agents using e.g. monocytes/ macrophages as "Trojan horses" to deliver these nanoparticles across the blood-brain barrier and diagnose or treat pathologies of the central nervous system.
- MeSH
- aminy MeSH
- kovové nanočástice * MeSH
- lidé MeSH
- polyethylenglykoly MeSH
- zlato * MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
The antimicrobial activity of gold and silver nanoparticles (AuNPs, AgNPs), chitosan (CS) and their combinations was established by determining the minimum inhibitory concentration for planktonic (MICPC80) and biofilm growth (MICBC80), for biofilm formation (MICBF80), metabolic activity (MICBM80) and reduction (MICBR80), and for the metabolic activity of preformed biofilm (MICMPB80). Biofilms were quantified in microtitre plates by crystal violet staining and metabolic activity was evaluated by the MTT assay. Chitosan effectively suppressed biofilm formation (0.31-5 mg ml-1) in all the tested strains, except Salmonella enterica Infantis (0.16-2.5 mg ml-1) where CS and its combination with AgNPs induced biofilm formation. Nanoparticles inhibited biofilm growth only when the highest concentrations were used. Even though AuNPs, AgNPs and CS were not able to remove biofilm mass, they reduced its metabolic activity by at least 80%. The combinations of nanoparticles with CS did not show any significant positive synergistic effect on the tested target properties.
- MeSH
- antibakteriální látky chemie farmakologie MeSH
- biofilmy účinky léků růst a vývoj MeSH
- chitosan chemie farmakologie MeSH
- gramnegativní bakterie účinky léků MeSH
- grampozitivní bakterie účinky léků MeSH
- kovové nanočástice chemie MeSH
- mikrobiální testy citlivosti MeSH
- potravinářská mikrobiologie MeSH
- stříbro chemie farmakologie MeSH
- synergismus léků MeSH
- vztah mezi dávkou a účinkem léčiva MeSH
- zlato chemie farmakologie MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
The preparation of light-activated hybrid antibacterial agent combining the porphyrin molecules, bound to the silver nanoparticles (AgNPs) surface is reported. AgNPs were synthesized by N-methyl-2-pyrrolidone-initiated reduction without additional reducing agents. The chemical structure of protoporphyrin IX was modified with the aim to introduce thiol groups. The size distribution and shape features of AgNPs were checked using TEM and HRTEM microscopies. The introduction of thiol groups into the porphyrin was proved by IR spectroscopy. The AgNPs-porphyrin binding was performed in solution and confirmed by fluorescence quenching, Raman spectroscopy and energy-filtered transmission electron microscopy (EFTEM). The antibacterial tests were performed against S. epidermidis and E. coli upon to LED illumination and in the dark. The synergetic effect of AgNPs and porphyrin as well as light activation of the created antibacterial conjugates were observed.
- MeSH
- antibakteriální látky chemická syntéza farmakologie MeSH
- Escherichia coli účinky léků MeSH
- kovové nanočástice chemie ultrastruktura MeSH
- luminiscence MeSH
- mikrobiální testy citlivosti MeSH
- porfyriny chemická syntéza chemie farmakologie MeSH
- Staphylococcus epidermidis účinky léků MeSH
- stříbro chemie farmakologie MeSH
- Publikační typ
- časopisecké články MeSH
Optical fibers have recently attracted a noticeable interest for biomedical applications because they provide a minimally invasive method for in vivo sensing, imaging techniques, deep-tissue photodynamic therapy or optogenetics. The silica optical fibers are the most commonly used because they offer excellent optical properties, and they are readily available at a reasonable price. The fused silica is a biocompatible material, but it is not bioresorbable so it does not decompose in the body and the fibers must be ex-planted after in vivo use and their fragments can present a considerable risk to the patient when the fiber breaks. In contrast, optical fibers made of phosphate glasses can bring many benefits because such glasses exhibit good transparency in ultraviolet-visible and near-infrared regions, and their solubility in water can be tailored by changing the chemical composition. The bioresorbability and toxicity of phosphate glass-based optical fibers were tested in vivo on male laboratory rats for the first time. The fiber was spliced together with a standard graded-index multi-mode fiber pigtail and an optical probe for in vitro pH measurement was prepared by the immobilization of a fluorescent dye on the fiber tip by a sol-gel method to demonstrate applicability and compatibility of the fiber with common fiber optics.
- MeSH
- fosfáty chemie metabolismus MeSH
- koncentrace vodíkových iontů MeSH
- krysa rodu rattus MeSH
- optická vlákna * MeSH
- oxid křemičitý chemie MeSH
- potkani Wistar MeSH
- zvířata MeSH
- Check Tag
- krysa rodu rattus MeSH
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
The antibacterial properties of poly(hydroxybutyrate) (PHB) non-woven fabric were explored in this study. The PHB was activated by plasma modification and subsequently processed with either immersion into a solution of nanoparticles or direct metallization. The wettability and surface chemistry of the PHB surface was determined. The thickness of the sputtered nanolayer on PHB fabric was characterized. It was found that plasma modification led to a formation of strongly hydrophilic surface, while the subsequent metallization by silver or gold resulted in a significantly increased water contact angle. Further, it was found that antibacterial activity may be controlled by the type of a metal and deposition method used. The immersion of plasma modified fabric into Ag nanoparticle solution led to enhanced antibacterial efficiency of PHB against Escherichia coli (E. coli). Direct silver sputtering on PHB fabric was proved to be a simple method for construction of a surface with strong antibacterial potency against both Escherichia coli (E. coli) and Staphylococcus epidermidis (S. epidermidis). We demonstrated the antibacterial activity of PHB fabric modified by plasma activation and consecutive selection of a treatment method for an effective antibacterial surface construction.
- MeSH
- antibakteriální látky chemie farmakologie MeSH
- Escherichia coli účinky léků MeSH
- mikrobiální testy citlivosti MeSH
- nanočástice chemie MeSH
- polyestery chemie farmakologie MeSH
- povrchové vlastnosti MeSH
- smáčivost MeSH
- Staphylococcus epidermidis účinky léků MeSH
- stříbro chemie MeSH
- Publikační typ
- časopisecké články MeSH
