The hygroscopicity of three commercial moisture-barrier film coatings, namely, Eudragit L30 D-55 (methacrylic acid-ethyl acrylate copolymer), Opadry AMB (polyvinyl alcohol based system), and Sepifilm LP 014 (hypromellose, microcrystalline cellulose, and stearic acid based formulation), was investigated using a dynamic vapor sorption apparatus. Moisture uptake by cast films and uncoated and coated tablet cores, which were designed to be hygroscopic, low hygroscopic, and waxy, was measured following exposure to repeat relative humidity (RH) cycles of 0-50-0-50-0%, 0-75-0-75-0%, and 0-90-0-90-0% RH at 25 degrees C. Eudragit cast film exhibited the fastest equilibration but was also the least hygroscopic. Sepifilm had the fastest sorption and took up the greatest mass of water. The rate of uptake for Opadry film was similar to Sepifilm. However, this film continued to sorb moisture for a longer period. When returned to 0% RH it retained moisture in the film showing that it had a high affinity for moisture within the film. The data for the different cores indicated that there was very little benefit in using a moisture barrier film on cores with low hygroscopicity, the mass gain being a sum of that which would be expected to sorb to the film and that which sorbs to the uncoated core. There was, however, some advantage for hygroscopic cores where, even though the barrier coatings allowed substantial water sorption into the core, the extent of this was less and the rate of uptake lower than for the uncoated sample.
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http://dx.doi.org/10.1080/03639040500306187 | DOI Listing |
J Mater Sci Mater Med
January 2025
Department of Nuclear Medicine, Chongqing University Cancer Hospital, No. 181 HanYu St, Shapingba District, Chongqing, 400030, PR China.
Human hair keratin, a natural protein derived from human hair, has emerged prominently in the field of wound repair, showcasing its unique regenerative capabilities and extensive application potential. However, it is a challenge for the keratin to efficiently therapy the impaired wound healing, such as combined radiation-wound injury. Here, we report a keratin/chitosan (KRT/CS) film for skin repair of chronic wounds in in rats with combined radiation-wound injury.
View Article and Find Full Text PDFJ Mol Model
January 2025
College of Mechanical Engineering, Changzhou University, Changzhou, Jiangsu Province, China.
Context: The flow equations are derived for describing the two-dimensional hybrid molecular-scale and continuum flows in the very small surface separation with inhomogeneous solid surfaces and they can be applied for designing the specific bearings. The aim of the present study is to solve this specific flow problem in engineering with normal computational cost. The flow factor approach model describes the flow of the molecule layer adjacent to the solid surface and the Newtonian fluid model describes the flow of the intermediate continuum fluid.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
January 2025
Northeastern University, Corrosion and Protection Center, NO. 3-11, Wenhua Road, Heping District, Shenyang, P. R. China, Shenyang, CHINA.
The dense passive film on 316L stainless steel is the key in its corrosion resistance. Its interactions with an electroactive biofilm are critical in deciphering microbial corrosion. Herein, an in-depth investigation using genetic manipulations and addition of an exogenous electron mediator found that extracellular electron transfer (EET) mediated by the electroactive S.
View Article and Find Full Text PDFDalton Trans
January 2025
Johnson Matthew Technology Centre, Blounts Court Rd., Sonning Common, RG4 9NH, UK.
A volatile heteroleptic open ruthenocene has been synthesised and characterised by NMR and single crystal X-ray diffraction. Using this compound as a precursor and oxygen as a co-reactant, a highly conductive Ru film has been deposited on Si with native oxide at 220 °C. Under the same deposition conditions, the film thickness obtained with the new compound has almost doubled compared to its homoleptic analogue.
View Article and Find Full Text PDFJ Sci Food Agric
January 2025
College of Food Science and Engineering, South China University of Technology, Guangzhou, China.
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