Synthesis and characterization of copolymer hydrogels based on N-isoprpylmethacrylamide and N-isopropylacrylamide for curcumin formulations

[M. Z. Urošević]

[13], 174 lista

Biografija autora sa bibliografijom: list. 162-171. Bibliografija: list. 116-141.

Chemistry and chemical technology

The aim of the doctoral dissertation was the development of a new matrix system based on a smart polymer carrier with an incorporated curcumin:2-hydroxypropyl-β-cyclodextrin inclusion complex to increase the solubility of curcumin and achieve its modified release. For this purpose, series of thermosensitive hydrogels based on N-isopropylmethacrylamide and N-isopropylacrylamide monomers were synthesized by free-radical polymerization with a different content of monomers and crosslinker. The characterization of the synthesized hydrogels was performed using the FTIR, XRD, SEM and DSC methods. The content of unreacted monomers was determined using the HPLC method. The degree and rate of swelling of hydrogels depending on the temperature, monomer content and crosslinker were determined gravimetrically. The swelling kinetics of p(NiPMAm-co-NiPAm) hydrogels was investigated, and the central composite design was applied as a mathematical model to describe the equilibrium swelling process of p(NiPMAm-co-NiPAm) hydrogels depending on the composition of the copolymer and the temperature of the surrounding medium. An inclusion complex of curcumin with 2-hydroxypropyl-β-cyclodextrin was prepared in order to increase the solubility of curcumin and characterized by FTIR, SEM, XRD, DSC and 1H-NMR methods. The applied characterization methods confirmed the incorporation of curcumin into the cavity of 2-hydroxypropyl-β-cyclodextrin, and the solubility phase showed that the solubility of curcumin in water increases. An increased antioxidant and antimicrobial activity of curcumin in the inclusion complex is a consequence of its increased solubility in water. The influence of curcumin and the curcumin:2-hydroxypropyl-β-cyclodextrin inclusion complex on the textural characteristics of Carbopol gel was investigated over the course of time. The results of the textural analysis show that curcumin and curcumin in the inclusion complex do not lead to statistically significant changes in the textural parameters of Carbopol gel over a 14-day period, which indicates the physical stability of the formulations. The curcumin:2-hydroxypropyl-β-cyclodextrin inclusion complex was incorporated into the synthesized and characterized p(NiPMAm-co-NiPAm) hydrogels. The characterization of the synthesized hydrogels with the curcumin:2-hydroxypropyl-β-cyclodextrin inclusion complex was performed using the FTIR, XRD, SEM and DSC methods, where the presence of curcumin in the hydrogels was confirmed. The synthesized p(NiPMAm-co-NiPAm) hydrogels provide a sustained release of curcumin. The Korsmeyer-Peppas model best describes the release of curcumin from the matrix system, while the mechanism of curcumin release is based on the diffusion from the polymer matrix of hydrogels.

N-izopropilmetakrilamid, N-izopropilakrilamid, hidrogelovi, kurkumin, inkluzioni kompleks, 2-hidroksipropil-β-ciklodekstrin

N-isopropylmethacrylamide, N-isopropylacrylamide, hydrogels, curcumin, inclusion complex, 2-hydroxypropyl-β-cyclodextrin

678.744-13:547.979.4 (043.3)

T 390

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