Publications by authors named "Hristo Penchev"

Ladder oligomers containing calixarene skeletons in the main chain-calix[4]resorcinarene (CRA) ladder macromolecules with open chain and cyclic macromolecules with double ring-like (Noria-type) topologies-bring particular research attention as functional materials with various applications. However, there is still a remarkable lack of studies into the synthesis of fully water-soluble derivatives of these interesting macromolecules. Research on this topic would allow their bio-based research and application niche to be at least revealed.

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Novel fibrous cellulosic substrates impregnated with meta-polybenzimidazole (PBI)-stabilized carbon nanotubes/zinc oxide with different weight content of ZnO and with the use of dimethylacetamide as dispersant media. The pristine ZnO nanoparticle powder was prepared by plant extract-mediated synthesis using L. The green synthesized ZnO possesses an average crystallite size of 15 nm.

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The use of biodegradable polyesters derived from green sources and their combination with natural abundantly layered aluminosilicate clay, e.g., natural montmorillonite, meets the requirements for the development of new sustainable, disposable, and biodegradable organic dye sorbent materials.

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The hepatoprotective properties of silibinin, as well its therapeutic potential as an anticancer and chemo-preventive agent, have failed to progress towards clinical development and commercialization due to this material's unfavorable pharmacokinetics and physicochemical properties, low aqueous solubility, and chemical instability. The present contribution is focused on the feasibility of using PEGylated calixarene, in particular polyoxyethylene-derivatized -octylcalix[8]arene, to prepare various platforms for the delivery of silibinin, such as inclusion complexes and supramolecular aggregates thereof. The inclusion complex is characterized by various instrumental methods.

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Hybrid nanofibrous materials with antibacterial activity consisting of yarns from N-carboxyethylchitosan (CECh) and poly(ethylene oxide) (PEO) that contain 5 wt% or 10 wt% silver nanoparticles (AgNPs) were prepared. This was achieved by electrospinning using formic acid as a solvent and as a reducing agent for silver ions. AgNO₃ was used as an Ag(+)-containing salt.

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Hybrid nanofibers from chitosan or N-carboxyethylchitosan (CECh) and silver nanoparticles (AgNPs) were prepared by electrospinning using HCOOH as a solvent. AgNPs were synthesized in situ in the spinning solution. HCOOH slowed down the cross-linking of the polysaccharides with GA enabling the reactive electrospinning in the presence of poly(ethylene oxide) (PEO).

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