In this study, some crucial parameters were determined of flexible polymer–organic solar cells prepared from an active layer blend of poly(3-hexylthiophene) (P3HT) and the fullerene derivative [6,6]-phenyl-C₆₁-butyric acid methyl ester (PCBM) mixed in 1:1 mass ratio and deposited from chlorobenzene solution by spin-coating on poly(ethylene terephthalate) (PET)/ITO substrates. Additionally, the positive effect of an electron transport layer (ETL) prepared from zinc oxide nanoparticles (ZnO np) on flexible photovoltaic elements’ performance and stability was investigated. Test devices with above normal architecture and silver back electrodes deposed by magnetron sputtering were constructed under environmental conditions. They were characterized by current-voltage (I–V) measurements, quantum efficiency, impedance spectroscopy, surface morphology, and time–degradation experiments. The control over morphology of active layer thin film was achieved by post-deposition thermal treatment at temperatures of 110–120 °C, which led to optimization of device morphology and electrical parameters. The impedance spectroscopy results of flexible photovoltaic elements were fitted using two R||CPE circuits in series. Polymer–organic solar cells prepared on plastic substrates showed comparable current–voltage characteristics and structural properties but need further device stability improvement according to traditionally constructed cells on glass substrates.

Polyion complex (PIC) micelles have gained an increasing interest, mainly as promising nano-vehicles for the delivery of various hydrophilic charged (macro)molecules such as DNA or drugs to the body. The aim of the present study is to construct novel functional PIC micelles bearing cell targeting ligands on the surface and to evaluate the possibility of a hydrophobic drug encapsulation. Initially, a pair of functional oppositely charged peptide-based hybrid diblock copolymers were synthesized and characterized. The copolymers spontaneously co-assembled in water into nanosized PIC micelles comprising a core of a polyelectrolyte complex between poly(L-aspartic acid) and poly(L-lysine) and a biocompatible mixed shell of disaccharide-modified poly(ethylene glycol) and poly(2-hydroxyethyl methacrylate). Depending on the molar ratio between the oppositely charged groups, PIC micelles varying in surface charge were obtained and loaded with the natural hydrophobic drug curcumin. PIC micelles’ drug loading efficiency, in vitro drug release profiles and antioxidant activity were evaluated. The preliminary results indicate that PIC micelles can be successfully used as carriers of hydrophobic drugs, thus expanding their potential application in nanomedicine.

Polymer micelles represent one of the most attractive drug delivery systems due to their design flexibility based on a variety of macromolecular synthetic methods. The environmentally safe chemistry in which the use or generation of hazardous materials is minimized has an increasing impact on polymer-based drug delivery nanosystems. In this work, a solvent-free green synthetic procedure was applied for the preparation of an amphiphilic diblock copolymer consisting of biodegradable hydrophobic poly(acetylene-functional carbonate) and biocompatible hydrophilic polyethylene glycol (PEG) blocks. The cyclic functional carbonate monomer 5-methyl-5-propargyloxycarbonyl-1,3-dioxane-2-one (MPC) was polymerized in bulk using methoxy PEG-5K as a macroinitiator by applying the metal-free organocatalyzed controlled ring-opening polymerization at a relatively low temperature of 60 °C. The functional amphiphilic block copolymer self-associated in aqueous media into stable micelles with an average diameter of 44 nm. The copolymer micelles were physico-chemically characterized and loaded with the plant-derived anticancer drug curcumin. Preliminary in vitro evaluations indicate that the functional copolymer micelles are non-toxic and promising candidates for further investigation as nanocarriers for biomedical applications.

Spherical nucleic acids (SNAs) have gained significant attention due to their unique properties allowing them to overcome the challenges that face current nanocarriers used for gene therapies. The aim of this study is to synthesize and characterize polymer–oligonucleotide conjugates of different architecture and to evaluate the possibility of forming SNAs with biodegradable cores. Initially, two types of azide (multi)functional polyester-based (co)polymers were successfully synthesized and characterized. In the next step, short oligonucleotide strands were attached to the polymer chains applying the highly efficient and metal-free “click” reaction, thus forming conjugates with block or graft architecture. Both conjugates spontaneously self-assembled in aqueous media forming nanosized SNAs with a biodegradable polyester core and a surface of oligonucleotide chains as evidenced from dynamic and electrophoretic light scattering measurements. The nano-assemblies were in vitro evaluated for potential cytotoxicity. Furthermore, the interactions of the newly synthesized SNAs with membrane lipids were studied. The preliminary results indicate that both types of polymer-based SNAs are good candidates for potential application in gene therapy and that it is worth to be further evaluated.

Mechanically and thermally stable novel gel polymer electrolytes (GPEs) have been prepared and applied in supercapacitor cells. Quasi-solid and flexible films were prepared by solution casting technique and formulated by immobilization of ionic liquids (ILs) differing in their aggregate state. A crosslinking agent and a radical initiator were added to further stabilize them. The physicochemical characteristics of the obtained crosslinked films show that the realized cross-linked structure contributes to their improved mechanical and thermal stability, as well as an order of magnitude higher conductivity than that of the non-crosslinked ones. The obtained GPEs were electrochemically tested as separator in symmetric and hybrid supercapacitor cells and showed good and stable performance in the investigated systems. The crosslinked film is suitable for use as both separator and electrolyte and is promising for the development of high-temperature solid-state supercapacitors with improved capacitance characteristics.

Podophyllotoxin (PPT) is used in the industrial production of efficient anticancer, antiviral and other drugs. Sinopodophyllum hexandrum or Podophyllum peltatum are natural sources of PPT, but at present they are considered as endangered species. Their PPT content is variable, depending on the growing conditions. Searching for new sources of PPT, some representatives of the genus Juniperus were found to exhibit efficient PPT biosynthesis. However, PPT is highly toxic and poorly soluble in water compound, which limits its clinical applications. In this connection, amphiphilic polymer micelles are considered to be suitable PPT carriers, aimed at increase in water solubility and decrease in toxicity. The present research deals with the evaluation of MPEG–polycarbonate block copolymer micelles loaded with PPT or juniper extracts. The active component-loaded polymer nanocarriers were characterized by dynamic and electrophoretic light scattering, as well as by transmission electron microscopy. The active component loading efficiency and loading capacity were also determined. Highly efficient antiproliferative activity of the loaded micelles was determined in a panel of cancer cell lines. The obtained amphiphilic nanocarriers, loaded with PPT-containing bioactive components, have application in future in vivo preclinical trials of their pharmacokinetics and pharmacodynamics as potential therapeutical agents in the prospective nanomedicine.