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Thermoresponsive amphiphilic conetworks comprising poly(2-ethyl-2-oxazoline) (PEtOx), 2-hydroxyethyl methacrylate, and 2-hydroxypropyl acrylate segments have been studied as new platforms for delivery of drug with limited solubility. Series of conetworks of varied composition were synthesized and swelling kinetics in aqueous media and ethanol were followed. The platforms were loaded with the hydrophobic drug ibuprofen by swelling in its ethanol solution. The structure and properties of the drug carriers were investigated by scanning electron microscopy and differential scanning calorimetry. The release kinetics profiles of ibuprofen from the studied platform were established. The investigation proved the feasibility of the PEtOx-based amphiphilic conetworks as highly effective platforms for sustained ibuprofen delivery.

SummaryInterpenetrating polymer networks (IPNs) of poly(acrylic acid) (PAA) and polyacrylamide (PAAm) were synthesized and applied as drug delivery systems for verapamil hydrochloride (VPM). The IPN network density was controlled by changing IPN composition. Thus, when increasing the PAAm to PAA weight ratio, the network density increases as revealed by the equilibrium swelling ratio and microhardness measurements. The SEM study of the IPNs’ morphology showed phase separation at nano level where PAAm domains with size below 100 nm are finely dispersed into the PAA matrix. The thermal study on the IPNs confirmed that both components are finely mixed as one Tg was detected for all IPNs’ compositions. Tg vs. composition dependence obeyed the Gordon–Taylor equation and deviated negatively from the Fox equation thus confirming weak interactions between PAA and PAAm. The VPM loading into PAA/PAAm IPNs resulted into amorphization of the drug as well as in a IPNs’ Tg increase as revealed by differential scanning calorimetry (DSC). The in vitro release of VPM shows that the IPNs of PAA/PAAm are suitable systems for sustained drug delivery. It was established that by changing IPNs’ composition it is possible to obtain different drug release kinetic profiles.

Cryogenic treatment and UV irradiation were exploited for the preparation of super‐macroporous cryogels from non‐modified high‐molar‐mass dextran. The photo‐crosslinking process was initiated by (4‐benzoylbenzyl)trimethylammonium chloride and N,N′‐methylenebisacrylamide (BAAm) was used as a crosslinking agent. Gel fraction yield and degree of swelling of the dextran cryogels were determined gravimetrically. Cryogel morphology and mechanical properties were studied using environmental scanning electron microscopy and dynamic rheological measurements, respectively. The effects of dextran concentration in the initial polymer solution, polymer molar mass and BAAm content on the crosslinking efficacy, physico‐mechanical properties and morphology of the cryogels were evaluated. The dextran cryogels were assessed as carriers of the model water‐soluble drug metoprolol. © 2017 Society of Chemical Industry

Novel interpenetrating polymer networks (IPN) of poly(methacrylic acid) (PMAA) and polyacrylamide (PAAm) were synthesized and characterized in terms of their swelling ability, microhardness and morphology. The potential of these new polymeric materials as a sustained delivery system for cationic drug was revealed. The study demonstrates that the IPN's composition is a powerful tool to control the IPN's structure and properties and hence their performance as a new polymeric system for sustained drug delivery.

Aripiprazole is a second‐generation atypical antipsychotic used for the treatment of schizophrenia, bipolar disorder, tic disorders, major depressive disorder, etc. However, aripiprazole is poorly soluble in water and many efforts are focused on developing delivery systems which can improve the solubility and the therapeutic activity of aripiprazole. In this contribution, the fabrication of novel cryogel carriers comprising β‐cyclodextrin (β‐CD) moieties for improved solubilization of aripiprazole is reported. Cryogels are synthesized by photochemical crosslinking of N,N‐dimethylacrylamide (DMA) and β‐CD triacrylate (β‐CD‐Ac3) in frozen aqueous system using H2O2 as initiator. The effect of DMA/β‐CD‐Ac3 mass ratio on the reaction efficiency, physico‐mechanical properties of cryogel, and drug loading efficiency is evaluated. The cryogel carriers are loaded with aripiprazole via procedure favoring inclusion of drug molecules into the hydrophobic cavity of β‐CD. The release of aripiprazole from PDMA/β‐CD carriers at pH 1.2 and 6.8 is studied and compared to the pure PDMA carriers.