Various artificial membranes (e.g. PAMPA) and cellular-based membranes (e.g. Caco-2) are used for screening during early stages of drug discovery. However, these methods are not well suited for evaluation of pharmaceutical formulations and the effects of various excipients on drug availability. When drug molecules permeate biological membranes they encounter two types of permeation resistance, a membrane resistance in the lipophilic membrane and diffusion resistance in the unstirred water layers adjacent to both surfaces of the lipophilic membrane. We have developed an artificial membrane that is cheap and simple to prepare. The unstirred water layer consists of a hydrated semi-permeable cellophane membrane with a molecular weight cutoff (MWCO) of 12,000-14,000 Da and a lipophilic membrane of pure n-octanol in a nitrocellulose matrix. In the diffusion cell the hydrated cellophane membrane (thickness 210-230 microm) is on the donor side and the lipophilic octanol membrane (thickness about 120 microm) on the receptor side. Permeation of ionizable lipophilic drug molecules was diffusion-controlled when the drug was unionized but lipophilic membrane controlled when the drug was ionized. Drug permeation patterns from cyclodextrin containing formulations through the membrane were similar to those previously observed for biological membranes such as hairless mouse skin and the eye cornea.
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http://dx.doi.org/10.1016/j.ijpharm.2006.07.009 | DOI Listing |
Curr Top Dev Biol
January 2025
Department of Pharmaceutics, School of Pharmacy, University of Washington.
The active metabolite of vitamin A, all-trans-retinoic acid (atRA), is critical for maintenance of many cellular processes. Although the enzymes that can synthesize and clear atRA in mammals have been identified, their tissue and cell-type specific roles are still not fully established. Based on the plasma protein binding, tissue distribution and lipophilicity of atRA, atRA partitions extensively to lipid membranes and other neutral lipids in cells.
View Article and Find Full Text PDFToxicology
January 2025
Deparment of clinical pharmacy, Jieyang People's Hospital, 522000, China. Electronic address:
Drug-induced autoimmunity (DIA) is a non-IgE immune-related adverse drug reaction that poses substantial challenges in predictive toxicology due to its idiosyncratic nature, complex pathogenesis, and diverse clinical manifestations. To address these challenges, we developed InterDIA, an interpretable machine learning framework for predicting DIA toxicity based on molecular physicochemical properties. Multi-strategy feature selection and advanced ensemble resampling approaches were integrated to enhance prediction accuracy and overcome data imbalance.
View Article and Find Full Text PDFMolecules
January 2025
Preclinical Department, Faculty of Medicine & Defence Health, Universiti Pertahanan Nasional Malaysia, Kuala Lumpur 57000, Malaysia.
2-phenylchromen-4-one, commonly known as flavone, plays multifaceted roles in biological response that can be abundantly present in natural sources. The methoxy group in naturally occurring flavones promotes cytotoxic activity in various cancer cell lines by targeting protein markers, in facilitating ligand-protein binding mechanisms and activating cascading downstream signaling pathways leading to cell death. However, the lipophilic nature of these analogs is a key concern as it impacts drug membrane transfer.
View Article and Find Full Text PDFFoods
January 2025
Department of Pharmacognosy, Faculty of Pharmacy, "Victor Babes" University of Medicine and Pharmacy Timişoara, Eftimie Murgu Square, No. 2, 300041 Timişoara, Romania.
There is a growing need for safer alternatives to synthetic additives commonly used in lipophilic carriers for products such as foods, pharmaceuticals, personal care items, and cosmetics. Natural antioxidants, which prevent lipid peroxidation while providing additional health benefits, offer a promising solution. Evening primrose oil, a rich source of antioxidant compounds with numerous biological benefits, emerges as a potential natural preservative for oil-based products.
View Article and Find Full Text PDFFront Pharmacol
January 2025
Hubei Shizhen Laboratory, Wuhan, China.
Introduction: The mortality rate for liver cancer is extremely high but clinical treatments have not made much progress, so it is necessary to develop anticancer agents with lower toxicities and more effective liver-targeting drug delivery systems (LTDDSs). At present, LTDDSs mediated by the asialoglycoprotein receptor (ASGPR) show excellent effects at improving the liver-targeting and antitumor effects of drugs. However, the galactosyl ligands are typically prepared by chemical synthesis and have some shortcomings.
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