Influence of various drugs on the glass transition temperature of poly(vinylpyrrolidone): a thermodynamic and spectroscopic investigation

Nair, R. V.; Nyamweya, Nasser; Gonen, Shmuel; Martı́nez-Miranda, L. J.; Hoag, Stephen W.

doi:10.1016/s0378-5173(01)00767-0

Cited by 203 publications

(132 citation statements)

References 27 publications

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“…In the present study, the ratio of drug to polymer was much greater, and so the effect of the drug on the PVP FTIR spectrum was clearly evident. In another research, the displacement of bands related to PVP and the creation of a broader band when mixed with carbamazepine has been attributed to the establishment of hydrogen bonds between functional groups (26). Considering that the aim of the study was to obtain a fast-dissolving formulation of loratadine nanofibers, drug release from the nanofibers was compared with the solid dispersion form to identify which one exhibits a faster release.…”

Section: Resultsmentioning

confidence: 99%

The Design and Evaluation of a Fast-Dissolving Drug Delivery System for Loratadine Using the Electrospinning Method

Akhgari

Dezfuli

Rezaei

et al. 2016

Jundishapur J Nat Pharm Prod

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Background: Due to their optimal mechanical and biological properties, nanofibers have numerous medical applications. Electrospinning is one of the widely used techniques for generating drug-containing nanofibers. Objectives: The aim of this study was to assess the use of the electrospinning method to prepare fast-dissolving loratadine nanofibers. Materials and Methods: Polyvinylpyrrolidone (PVP) nanofibers containing loratadine were produced using the electrospinning method. A full factorial design was employed to evaluate the formulations, including the four following variables: the concentration of PVP, the ratio of drug to polymer, the feed rate, and the voltage applied at two levels. After preparing the samples, assessments were carried out using scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, and differential scanning calorimetry (DSC). Dissolution tests and determination of the time of disappearance were also carried out. It was observed that reducing the concentration of polymer, reducing the feed rate, and increasing the voltage applied to the polymeric solution up to an adequate amount allowed the possibility of creating nanofibers with a smaller diameter and greater uniformity. Results:The results showed that the fiber diameter and the amount of loratadine affected the drug release and the disappearance time of nanofibers. The smaller the fiber diameter and drug amount, the faster the solubility and the release time of nanofibers. Conclusions: It was concluded that electrospinning can be a suitable method for preparing fast-dissolving loratadine nanofibers.

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Section: Resultsmentioning

confidence: 99%

The Design and Evaluation of a Fast-Dissolving Drug Delivery System for Loratadine Using the Electrospinning Method

Akhgari

Dezfuli

Rezaei

et al. 2016

Jundishapur J Nat Pharm Prod

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“…Figure 2 shows the FTIR spectrum of CBZ, NCT, their physical mixture, and cocrystal prepared by different methods. The stretching of the primary amide group in CBZ was represented by absorption bands at 3,465 and 3,157 cm −1 , respectively, which could be assigned to the free anti-NH (asymmetrical) and hydrogen-bonded syn-NH (symmetrical) vibration (5,32). The absorption band at 1,677 cm −1 was due to carbonyl (−C=O) stretching.…”

Section: Solubilitymentioning

confidence: 99%

Physico-mechanical and Stability Evaluation of Carbamazepine Cocrystal with Nicotinamide

et al. 2011

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Abstract. The focus of this investigation was to prepare the cocrystal of carbamazepine (CBZ) using nicotinamide as a coformer and to compare its preformulation properties and stability profile with CBZ. The cocrystal was prepared by solution cooling crystallization, solvent evaporation, and melting and cryomilling methods. They were characterized for solubility, intrinsic dissolution rate, chemical identification by Fourier transform infrared spectroscopy, crystallinity by differential scanning calorimetry, powder X-ray diffraction, and morphology by scanning electron microscopy. Additionally, mechanical properties were evaluated by tensile strength and Heckel analysis of compacts. The cocrystal and CBZ were stored at 40°C/94% RH, 40°C/75% RH, 25°C/60% RH, and 60°C to determine their stability behavior. The cocrystals were fluffy, with a needle-shaped crystal, and were less dense than CBZ. The solubility profiles of the cocrystals were similar to CBZ, but its intrinsic dissolution rate was lower due to the high tensile strength of its compacts. Unlike CBZ, the cocrystals were resistant to hydrate transformation, as revealed by the stability studies. Plastic deformation started at a higher compression pressure in the cocrystals than CBZ, as indicated by the high yield pressure. In conclusion, the preformulation profile of the cocrystals was similar to CBZ, except that it had an advantageous resistance to hydrate transformation.

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“…31 The GordonTaylor equation is one of the most used expressions to describe the T g -composition dependence of miscible polymer blends 30,32 and drug/polymer blends 33,34 …”

Section: Resultsmentioning

confidence: 99%

Blends of Paclitaxel with POSS-Based Biodegradable Polyurethanes: Morphology, Miscibility, and Specific Interactions

Guo

Knight

Wu³

et al. 2010

Macromolecules

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The morphology, miscibility, and specific interactions of paclitaxel (PTx) with a family of polyhedral oligosilsesquioxane (POSS)-based biodegradable thermoplastic polyurethanes (POSS TPUs) were investigated systematically using wide-angle X-ray diffraction (WAXD), differential scanning calorimetry (DSC), and Fourier transform infrared spectroscopy (FTIR). These POSS TPUs incorporate an alternating multiblock structure formed by POSS hard segments and the soft segments composed of polylactide/caprolactone copolymer (P(DLLA-co-CL)). They feature variable poly(ethylene glycol) (PEG) content from 0 to 14 wt % through adjusting the poly(ethylene glycol) (PEG) molecular weight in P(DLLA-co-CL) soft segments of fixed molar mass of M _ n = 12 kg/mol and further to 52 wt % utilizing pure PEG M _ n = 1 kg/mol in the soft segments. Using WAXD, it was found that PTx is amorphous in all proportions in the PTx/POSS TPU blends prepared using a solutioncasting method. Interestingly, the PTx not only exhibits excellent miscibility in all of these PTx/POSS TPU blends over the whole range of the drug concentration, but also serves as an antiplasticizer by increasing the blend T g gradually from the polymer T g up to the T g of amorphous PTx. The T g -composition dependences in these blends were well fitted by the Gordon-Taylor equation. The glass transition breadth of the blends increases significantly only for drug concentrations higher than 50 wt % for most of the POSS TPUs, suggesting some spatial heterogeneity at these high drug concentrations. On the other hand, the slight increment of the blend melting temperature, T m , and latent heat, ΔH, indicates enhanced phase separation between the POSS hard segments and the TPU soft segments upon drug incorporation. Gordon-Taylor analysis and FTIR results confirm that the PEG incorporated in the POSS TPUs exhibits strong H-bonding interactions with the PTx. Although PEG can promote the favorable interactions in the PTx/POSS TPU blends, we showed that the more hydrophobic LA/CL repeat units are still required in the soft segments in order to achieve molecular-level miscibility. This systematic investigation of the PTx/POSS TPU systems may be of great value to design plasticizer/antiplasticizer for new polymer materials with controlled and tailored properties, especially for those PLA-or PCL-based biodegradable polymer systems.

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Influence of various drugs on the glass transition temperature of poly(vinylpyrrolidone): a thermodynamic and spectroscopic investigation

Cited by 203 publications

References 27 publications

The Design and Evaluation of a Fast-Dissolving Drug Delivery System for Loratadine Using the Electrospinning Method

The Design and Evaluation of a Fast-Dissolving Drug Delivery System for Loratadine Using the Electrospinning Method

Physico-mechanical and Stability Evaluation of Carbamazepine Cocrystal with Nicotinamide

Blends of Paclitaxel with POSS-Based Biodegradable Polyurethanes: Morphology, Miscibility, and Specific Interactions

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