A hybrid of poly-l-lactic acid (PLA) and poly-epsilon-caprolactone (PCL) system was designed using hydrophilic generally regarded as safe (GRAS) protein, egg albumin (EA), and fabricated as nanofiber mats (NM) to facilitate improved cell interactions and functionality. Our studies include, preparation and analysis of physicochemical properties of NM. Surface morphology of NM was smooth with the diameter ranging from 250 to 400 nm. The contact angle of NM decreased from 80 to 45 degrees with the increase in EA concentration. The rate and extent of swelling was increased 3-folds with the addition of EA. Release studies of NM showed maximum amount of MTz was released with the increase in MTz concentration (>85%). The MTz interaction with EA and structure stability of EA was confirmed from fluorescence and circular dichroism studies. NM showed increase in inhibition of bacterial growth of Staphylococcus aureus and Escherichia coli with the increase in MTz concentration. Cell viability of the NM was >80% and also, the cell proliferation increased as EA content increased. NM hemolytic activity was less than 5% suggesting compatibility. Hence, results concluded that EA had regulated hydrophobicity, promoted cell interactions, and proliferation and therefore, NM is considered safe for tissue regeneration.
Purpose Curcumin exists in three polymorphic forms: one monoclinic form and two orthorhombic forms. This work aims to investigate the efficacy of curcumin polymorphs in transdermal drug delivery by formulating curcumin polymorphs and their incorporation in polymeric films. Methods Monoclinic form, Form 1, was precipitated by liquid antisolvent technique from acetone solutions, whereas orthorhombic form, Form 2, was obtained by vacuum evaporation of solutions of curcumin in a mixed solvent of chloroform and hexane (60:40%v/v). The other orthorhombic form, Form 3, was precipitated from dimethylsulfoxide solutions. All three curcumin polymorphs were incorporated into polymeric films made of low molecular weight hydroxypropyl methyl cellulose (HPMC E5LV) along with different plasticizers, and permeation enhancers. Radical scavenging activity and cytotoxicity of curcumin polymorphs on human melanoma cell lines were evaluated. Water uptake, in-vitro release, and in-vitro permeation studies on HPMC films loaded with curcumin polymorph were carried out. Results Cytotoxicity studies on human melanoma cells (SK-MEL-28) showed that Form 2 results in the highest cell inhibition. Among all three curcumin polymorphs, the free radical scavenging activity of Form 3 was found to be the highest. HPMC films loaded with Form 3 exhibited higher water uptake and higher curcumin release profiles at pH of 5.5 (95.3% in 20 h) and pH 7.4 (79.8% in 20 h) as well as the highest in-vitro permeation compared to the other two curcumin forms. Conclusion Overall, orthorhombic curcumin polymorphs (i.e., Form 2 and Form 3) showed a higher propensity for transdermal drug delivery as compared to the monoclinic curcumin (Form 1).
Sonoprecipitation of Fenofibrate (FNB) was carried out in the presence of polymeric additives and surfactants. The particle size and morphology was found to be significantly affected by the mixing conditions and the type of additives used. In order to understand the mechanism by which the additives affect FNB particle growth and morphology, intermolecular interactions between the additive and FNB crystal surfaces were modeled. Among the additives used, Tween 80 was found to be a great habit modifier. Hydrogen bonding interactions between Tween 80 and FNB molecules exposed on the (010) face of FNB particles leads to a needle-like morphology. The experimental and modelling studies indicate that hydroxyl propyl methyl cellulose (HPMC) and bovine serum albumin (BSA) show stronger crystal growth inhibition effect and provide better stabilization compared to polyvinyl pyrolidone (PVP) and Tween 80. FNB particles precipitated with ultrasound and additives were found to exhibit faster drug release profiles compared to the particles precipitated without ultrasound but in the presence of additives.
Understanding thermodynamic stability relationship among polymorphs of any active pharmaceutical ingredient (API) is a necessary step for drug formulation development. Knowledge of such relationship enables identification of a stable polymorphic form at the prevalent conditions. Curcumin, a pharmaceutically active ingredient found in herbal spice turmeric, exists in three polymorphic forms; a monoclinic form (Form 1) and two orthorhombic forms (Form 2 and Form 3). However, thermodynamic stability relationships among curcumin polymorphs have not been ascertained yet. This work therefore, was focused on understanding thermodynamic stability relationships among curcumin polymorphs. During purification of curcumin, the pressure applied for vacuum evaporation of organic solvent was found to significantly affect the polymorphic outcome. Form 1 was obtained at pressures ranging from 300 to 400 mbar whereas Form 2 was obtained at pressures ranging from 100 to 200 mbar. Form 3 was obtained by liquid antisolvent precipitation using ultrasound and Bovine Serum Albumin (BSA) as an additive. The obtained polymorphs were characterized by X-ray diffraction (XRD) and Differential Scanning Calorimetry (DSC) techniques. Relative stability of polymorphs was established by conducting solvent mediated transformation studies, thermal analysis through DSC and variable temperature X-ray diffraction studies (VT-XRD). It was observed that Form 2 and Form 3 irreversibly convert to Form 1 upon heating. Further, Form 2 and Form 3 convert to Form 1 in aqueous organic solutions at temperatures ranging from 0 degrees C to 50 degrees C. Thus, the curcumin polymorphs were found to be monotropically related to each other with the monoclinic form (Form 1) being the most stable form. (C) 2018 The Society of Powder Technology Japan. Published by Elsevier B.V. and The Society of Powder Technology Japan. All rights reserved.
Developing drug formulations for poorly water-soluble drugs is a major challenge for pharmaceutical industries as the poor water solubility limits bioavailability of these drugs. Production of nanoparticles/microparticles of these drugs is one of the ways to improve dissolution rates by increasing interfacial area for dissolution. Curcumin, a compound obtained from the rhizome of curcuma longa (turmeric roots), is a pharmaceutically viable molecule. However, poor aqueous solubility limits its therapeutic use. In this work, we report studies conducted to continuously produce aqueous suspensions of curcumin nano/micro particles. Influence of process parameters such as ultrasound, additives, and solvent to antisolvent ratio on polymorphic outcome and morphology of precipitated particles has been investigated. Ultrasound was found to greatly influence the polymorphic form and the morphology of precipitated particles. Nucleation rates, mixing time, and solid-liquid interfacial energies were also estimated to understand the effect of various processing parameters on the precipitation process.
In this report, we demonstrated an interesting application of a bioderived material for the dye sensitized solar cells (DSSCs). Egg white, the clear liquid in a hen's egg, which possesses a remarkable gelling/cross-linking ability, was applied in the form of a gel electrolyte in a DSSC architecture to enhance its durability. A hybrid gel composed of poly(acrylic acid), polyaniline and egg albumen was synthesized, and the cell efficiency, stability and durability of the corresponding DSSC device were studied in detail. The dye sensitized solar cell with the egg albumen based electrolyte demonstrated a conversion energy efficiency of 4.6%. Further, a chemically modified egg albumen with ethylenediaminetetraacetic dianhydride showed improved cross-linking, microstructural and conductivity properties of the gel, and yielded a remarkable 5.75% conversion efficiency. Electrochemical impedance spectroscopy data showed favorable characteristics for charge transport through the modified gel and supported the efficiency observations very well.