In the present work, non-woven, non-regenerated cellulose wound dressing was subjected to in situ silver (Ag) deposition in the form of silver chloride (AgCl) under various reaction conditions. The studied reaction parameters were as follows: time, temperature, and reactants´ concentration. AgCl was bound on the cellulose via two-step process. Firstly, the silver ions (Ag+) were attracted to cellulose in the solution of silver nitrate (AgNO3). Secondly, Ag+ were precipitated directly on the cellulose by immersing the samples into the solution of sodium chloride (NaCl). The prepared samples were examined on the amount of bound and released Ag, and the release was studied both in water and in simulated body fluids. The reaction parameters significantly affected the amount of bound and released Ag, the difference of released Ag was as high as 75%. The key parameter in the process was reactants´ concentration. Non-regenerated cellulose modified with AgCl was antibacterially active.
Novel nanofibers mats were fabricated by electrospinning of polyvinyl alcohol/hyaluronan (PVA/HA) solutions in the presence of silver nanoparticles (AgNPs). The AgNPs were synthesized by in-situ chemical reduction of silver ions (Ag+) using HA as a reducing and stabilizing agent. Narrow size distribution and spherical shape of AgNPs were achieved by optimizing the initial silver nitrate concentration (0.01 to 1 M) and reaction time (10-60 min). HA-AgNPs nanocomposite and PVA/HA-AgNPs nanofibrous mats were fabricated by electrospinning technique from aqueous solution containing a different mass ratio of PVA and HA-AgNPs and characterized by UV/Vis spectroscopy, SEM, TEM, DLS, XRD, TGA, and ATR-FTIR. Mechanical and rheological properties were also investigated and discussed. The novel nanofibrous mats show great potential in skin regeneration and drug carrier applications.
- MeSH
- dusičnan stříbrný chemie MeSH
- elektrochemie MeSH
- ionty MeSH
- kovové nanočástice chemie MeSH
- kyselina hyaluronová chemie MeSH
- nanokompozity chemie MeSH
- nanovlákna MeSH
- nosiče léků MeSH
- obvazy MeSH
- polyvinylalkohol chemie MeSH
- povrchové vlastnosti MeSH
- reologie MeSH
- rozpouštědla MeSH
- spektroskopie infračervená s Fourierovou transformací MeSH
- stříbro chemie MeSH
- technologie zelené chemie * MeSH
- velikost částic MeSH
- Publikační typ
- časopisecké články MeSH
The polyaniline (PANI) base was ball-milled with silver nitrate in the solid state. Samples were prepared at various mole ratios of silver nitrate to PANI constitutional units ranging from 0 to 1.5 for three processing times, 0, 5, and 10 min. The emeraldine form of PANI was oxidized to pernigraniline, and the silver nitrate was reduced to metallic silver. Nitric acid is a byproduct, which may protonate the residual emeraldine and pernigraniline. The changes occurring in the structure of PANI are discussed on the basis of Fourier transform IR and Raman spectroscopies. Raman spectra revealed the formation of pernigraniline salt. The reaction between the two nonconducting components, emeraldine base and silver nitrate, produced a mixture of two conducting components, emeraldine or pernigraniline nitrate and metallic silver. The accompanying conductivity changes were determined. The increase in the conductivity of the original base, 10(-9) S cm(-1), up to 10(-2) S cm(-1) was found to depend on the mole ratio of silver nitrate to PANI base and on the processing time of the components in the ball mill.
- MeSH
- aniliny chemie MeSH
- časové faktory MeSH
- chemické modely MeSH
- chemie organická metody MeSH
- dusičnan stříbrný chemie MeSH
- elektrická vodivost MeSH
- kyslík chemie MeSH
- polymery chemie MeSH
- Ramanova spektroskopie metody MeSH
- spektroskopie infračervená s Fourierovou transformací metody MeSH
- stříbro chemie MeSH
- testování materiálů MeSH
- transmisní elektronová mikroskopie metody MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Byl testován vliv abiotického elicitoru – AgNO3 v různých koncentracích na produkci flavonoidů v kalusové kultuře Ononis arvensis L. Použití tohoto abiotického elicitoru se osvědčilo pro zvýšení produkce flavonoidů v kultuře in vitro. Maximální produkce bylo dosaženo po 24 hodinové elicitaci AgNO3 v koncentraci c1 (0,5 mg/l) – zvýšení o 934 % oproti kontrole (bez působení elicitoru).
The study tested the effect of abiotic elicitor, AgNO3, in different concentrations, on the production of flavonoids in the callus culture Ononis arvensis L. The use of this abiotic elicitor proved to be good to increase the production of flavonoids in in vitro culture. The maximal production was achieved after a 24-hour elicitation with AgNO3 in a concentration c1 (0.5 mg/l) – an increase by 934 % versus the control (without the elicitor’s action).
- MeSH
- biotechnologie ekonomika metody trendy MeSH
- dusičnan stříbrný chemie MeSH
- finanční podpora výzkumu jako téma MeSH
- flavonoidy chemie metabolismus terapeutické užití MeSH
- lidé MeSH
- techniky tkáňových kultur metody statistika a číselné údaje využití MeSH
- vyšší rostliny klasifikace MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- srovnávací studie MeSH
