Challenges of Dissolution Methods Development for Soft Gelatin Capsules.

Recently, the development of soft gelatin capsules (SGCs) dosage forms has attracted a great deal of interest in the oral delivery of poorly water-soluble drugs. This is attributed to the increased number of poorly soluble drugs in the pipeline, and hence the challenges of finding innovative ways of developing bioavailable and stable dosage forms. Encapsulation of these drugs into SGCs is one of the approaches that is utilized to deliver the active ingredients to the systemic circulation to overcome certain formulation hurdles. Once formulated, encapsulated drugs in the form of SGCs require suitable in vitro dissolution test methods to ensure drug product quality and performance. This review focuses on challenges facing dissolution test method development for SGCs. A brief discussion of the physicochemical and formulation factors that affect the dissolution properties of SGCs will be highlighted. Likewise, the influence of cross-linking of gelatin on the dissolution properties of SGCs will also be discussed.

One-pot electrodeposition, characterization and photoactivity of stoichiometric copper indium gallium diselenide (CIGS) thin films for solar cells.

Herein we report the one-pot electrodeposition of copper indium gallium diselenide, CuIn(1-x)Ga(x)Se(2) (CIGS), thin films as the p-type semiconductor in an ionic liquid medium consisting of choline chloride/urea eutectic mixture known as Reline. The thin films were characterized by scanning electron microscopy with energy dispersive X-ray analysis, transmission electron microscopy, X-ray photoelectron spectroscopy, Raman microspectroscopy, and UV-visible spectroscopy. Based on the results of the characterizations, the electrochemical bath recipe was optimized to obtain stoichiometric CIGS films with x between 0.2 and 0.4. The chemical activity and photoreactivity of the optimized CIGS films were found to be uniform using scanning electrochemical microscopy and scanning photoelectrochemical microscopy. Low-cost stoichiometric CIGS thin films in one-pot were successfully fabricated.

Effect of short term over-supplementation of ascorbic acid on hematology, serum biochemistry, and growth performance of neonatal dairy calves.

The objectives of the present study were to investigate effects of over-supplementation of ascorbic acid on hematology, serum biochemistry and weight gain in Holstein dairy calves. A total of 90 Holstein dairy calves were randomly assigned to receive one of two treatments. Ascorbic acid was administered orally to treatment group (n=44) as follows: three times 1000 mg a day during first week; two times 1000 mg a day during second week; one time 1000 mg a day during third week. No ascorbic acid was administered to control group (n=46). The number of lymphocytes (at day 14 after birth) and monocytes (at day 30 after birth) were significantly lower in ascorbic acid fed calves than control ones. The calves in treatment group had a significantly lower concentration of fibrinogen at day 30 after birth. Ascorbic acid fed calves showed significantly increased concentrations of albumin at day 60 after birth. No significant differences were seen for beta and gamma globulin levels and albumin:globulin (A:G) between groups. Total weight gains were not different between groups. However, the female calves which were received ascorbic acid had significantly increased weight gain in comparison with female calves of control group.

Propagation failures, breathing fronts, and nonannihilation collisions in the ferroin-bromate-pyrocatechol system.

The emergence of propagating pulses was investigated with the photosensitive ferroin-bromate-pyrocatechol reaction in capillary tubes, in which various interesting spatiotemporal behaviors such as propagation failure, breathing fronts, and transitions between propagating pulses and fronts have been observed. Rather than a mutual annihilation, the collision of a propagating pulse and a growing front forces the front to recede gradually. A phase diagram in the pyrocatechol-bromate concentration space shows that the pulse instabilities take place throughout the conditions at which the system generates wave activities, suggesting that the presence of coupled autocatalytic feedbacks may facilitate the onset of pulse instabilities.

Gas production in the bromate-pyrocatechol oscillator.

A significant amount of gas production has been observed in the bromate-pyrocatechol oscillator under high concentrations of bromate and pyrocatechol. The observation is in contrast to the general perception that aromatic compounds can form bromate-based oscillators that are free of gas bubbles, which is a desired property in investigating pattern formation. Analysis with (1)H NMR, (13)C NMR, mass spectrometry, and X-ray crystallography illustrate the production of 5-(dibromomethylene)-2(5H)-furanone from pyrocatechol, where the loss of one carbon atom from the aromatic ring causes the formation of gas bubbles. Possible mechanisms have been proposed to explain the observed phenomenon.

Chemical oscillations and waves in the catalyzed bromate-pyrocatechol reaction.

Long time series of temporal oscillations and wave formation are observed in the catalyzed bromate-pyrocatechol reaction conducted in a batch reactor, in which the induction time is insensitive to the presence of ferroin but is greatly shortened by Ce(III) or Mn(II). On the other hand, the number of oscillations is significantly increased by ferroin, while it is less sensitive to Ce(III) and Mn(II). The ferroin-catalyzed system also exhibits strong photosensitivity, in which illumination could quench the oscillatory behavior. A phase diagram illustrates that the oscillatory behavior of the studied system is more sensitive to the ratio of [pyrocatechol]/[bromate] than their absolute concentrations. Reactions conducted in a spatially extended medium show that the ferroin-catalyzed system supports a two-stage pattern formation with the wave activity surviving for up to 10 h.