Cross-linked polymer networks, irrespective of the method of cross-linking, contain a fraction of unattached polymer (sol macromolecules). During swelling in a solvent of low molecular weight, the sol macromolecules participate in the swelling process as an athermal solvent. Also, sol macromolecules begin to diffuse out of the swollen polymer into the surrounding solvent bath until equilibrium is reached between the sol macromolecules within the polymer specimen and the molecules in the surrounding bath. Thus, a partially cross-linked polymer during swelling should be treated as a ternary system consisting of polymer network, a high molecular weight solvent, and a low molecular weight solvent. On the basis of the Flory-Rehner theory, a first model has been developed to predict the swelling behavior of such ternary system. Transient states are considered as quasi-steady state, and the final condition of equilibrium is evaluated. The effect of polymer molecules in the surrounding solvent bath on the swelling behavior was also studied. Swelling experiments of partially cross-linked high-density polyethylene in p-xylene were performed to evaluate the model predictions. The presence of sol macromolecules within the swollen gel increased the swelling while sol molecules in the surrounding bath decreased the swelling of the partially cross-linked polymer.

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Analysis of the binding interactions of ibuprofen and silicified-microcrystalline cellulose (SMCC) has been undertaken. Co-processing of ibuprofen with SMCC was carried out by solid state ball milling, and aqueous state equilibration followed by freeze drying to investigate the effect of silicified-microcrystalline cellulose on ligand. Molecular docking study revealed that ibuprofen formed complex through hydrogen bond with microcrystalline cellulose (MCC) and silicon dioxide (SiO 2); the binding energy between MCC and SiO 2 , and ibuprofen and SMCC were found as-1.11 and-1.73 kcal/mol respectively. The hydrogen bond lengths were varying from 2.028 to 2.056 Å. Interaction of Si atom of SMCC molecule with Pi-Orbital of ibuprofen has shown the bond length of 4.263 Å. Significant improvement in dissolution of ibuprofen has been observed as a result of interaction. Binary and ternary interactions revealed more stabilizing interactions with ibuprofen and SMCC compared to SMCC formation.

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Characterization of pore structure and pore wall crystal structure was performed on porous highdensity polyethylene (HDPE) material using scanning electron microscopy (SEM), transmission electron microscopy (TEM), and electron diffraction (ED). The porous HDPE material was obtained through crystallization from swollen cross-linked polyethylene gels (CSX process 1) in supercritical propane. SEM showed an open-pore structure of micron-sized pores, large void fraction, and surface area as well as thin yet rigid pore walls, making this material a good candidate for a variety of applications. TEM revealed oriented lamellar structure in the pore walls which was much different from structures found in typical bulk HDPE as well as that of the cross-linked HDPE before CSX processing. Electron diffraction results confirmed the presence of oriented lamellar stacking. On the basis of this oriented lamellar structure, possible mechanisms for crystallization and pore formation are suggested.

Vildagliptin (VID) is a dipeptidyl peptidase-4 (DPP-4) inhibitor used in controlling blood glucose level in type 2 diabetes. Vildagliptin improves beta cells function and is also suggested to effectively control the inflammation. The possible ocular anti-inflammatory property of vildagliptin has been explored using topically applied plasticized ocular film formulation. Film formulation was prepared by solvent cast and evaporation method using triethanolamine (TEA), dimethyl sulphoxide (DMSO), and polyethylene glycol 400 (PEG 400) as the plasticizer in HPMC hydrogel matrix base. Anti-inflammatory study was carried out in the carrageenan induced ocular rabbit model. Analytical methods confirmed that the drug was present almost in completely amorphized form in the film formulation. Level of hydration, swelling and erosion rate of the film played the controlling factor in the process of drug release, ocular residence and permeation. Maximum swelling rate of 363 h−1 has been shown by VHT compared to other formulation of VHD and VHP (174 and 242 h−1 respectively). Film containing DMSO exhibited highest in vitro release as well as ex vivo ocular permeation. Film formulation has shown a fast recovery of ocular inflammation in contrast to the untreated eye after inducing inflammation. Plasticized vildagliptin hydrogel film formulation could be utilized in the management and control of ocular inflammation particularly with diabetic retinopathy after proper clinical studies in higher animal and human individuals.

Background: Tablet manufacturing with direct compression is one of the leading industrial technique that consumes less time, labour and economic also. But the choice of excipients are critical in this case which will allow the drug to get compressed without granulation techniques. Purpose: Aceclofenac is a BCS class II non-steroidal anti-inflammatory drug, which exerts a low oral bioavailability because of low solubility in aqueous medium. The drug also suffers from compressibility and also shows poor tabletibility. Methods: We have attempted to improve tabletability by incorporating titanium dioxide (TiO 2) through kneading and solvent evaporation technique. Results: In the FTIR study revealed that NH and Cl aromatic stretching of aceclofenac has been affected significantly due to binding with TiO 2. DSC thermogram ascertained the partial amorphization of the drug in the formulations. Evaluated tabletability from the area under the applied pressure vs tensile strength curve (AUTC) of A1T1 has shown a poor value in contrast to other formulations.