Interpolymer Complexation Between Polyox and Carbopol, and Its Effect on Drug Release From Matrix Tablets

Interpolymer complexes of carbopol® 971 and poly(2-ethyl-2-oxazoline): Physicochemical studies of complexation and formulations for oral drug delivery

“…Clearly, POZ and C971 dispersed uniformly in the intact tablet prior to hydration, as reflected by the presence of their characteristic peaks with high intensities in the spectrum of PM, such as the peak of the carboxyl stretching band of C971 (1704 cm -1 ) and a "shoulder" of amide I of POZ (1633 cm -1 ). According to above discussed mechanism of IPCs formation and also the literature data (Takayama and Nagai, 1987;Satoh et al, 1989;Ozeki et al, 1998aOzeki et al, , 1998bTan et al, 2001;Zhang et al, 2016aZhang et al, , 2016bYusif et al, 2016;Szakonyi andZelko, 2016, Nguyen et al, 2016), the passage of the tablets through pH 1.2 media facilitates strong interaction between the polymers. However, the spectral and thermal analysis results did not provide any evidence for the complexation under these conditions: the band corresponding to the self-associated carboxylic groups (COOH) located at 1704 cm -1 showed a very minor shift to 1707 cm -1 and the presence of amide I stretching was observed at 1622 cm -1 ; Tg values at 51.7±0.9 o C and 131.9±0.8 o C observed are assigned to the pure POZ 50 kDa and C971, respectively.…”

Drug Extended-Release System Utilizing Micelle Formation of Highly Water-Soluble Drugs and a Counter Polymer

“…It has been reported that PEO and Carbomer form hydrogen bond-induced complexation, while the interaction is pHdependent. 43,44 The interaction began between pH 5.0 and 6.0 in an aqueous medium, and an insoluble interpolymer complex started to precipitate when the pH is reduced to 4.0. On the other hand, it was reported that PEO and Carbomer did not complex at pH 6.8, and the synergy was not strong enough to delay the release of theophylline tablets containing a mixture of the polymers to be not significantly slower than that from tablets containing individual polymers at pH6.8.43 As the in vitro dissolution study was implemented at pH6.8 in this article, the impact of complexation of these two polymers would be negligible.…”

Characterization of Eudragit types and Kollidon SR inter-polymer complexes and their effects on the drug release

“…However, the f 2 value more than 50 (58.27). The interaction between two polymers in the IPC system was mediated by a hydrogen bonding interaction, thus the mobility of polymer chain and permeability were reduced, as a consequence, the drug release retarded (Zhang et al, 2016a). In addition, in the non-IPC, the chain polymers depended on the characteristic of the single polymer and both polymers did not interact.…”

“…Either positive or negative effects are possible to be obtained depending on its interaction (Khutoryanskaya et al, 2014;Khutoryanskiy, 2007;Robertis et al, 2015). Several IPCs have been reported that it could be used to control the drug release, e.g., copovidone and Carbopol (Zhang et al, 2017), Polyox and Carbopol (Zhang et al, 2016a), polyethylene oxide and poly acrylic acid (Zhang et al, 2016b), and inter polyelectrolyte complexes using several polymers, such as Eudragit E, Eudragit L, hydroxyl propyl methyl cellulose (HPMC) succinic acid, chitosan, and poly acrylic acid (Jeganathan and Prakya, 2015;Moustafine et al, 2012;Moustafine and Bobyleva, 2006;Mustafin, 2011;Park et al, 2008). However, until to the date, there was no reported data about the characterization of IPC between poly-methacrylate copolymer [Eudragit types (Eudragit RS, L, and E)] and copolymer poly-vinyl acetate-copovidon (Kollidon SR) and their effects on the drug release.…”