Proteolysis targeting chimeras (PROTACs) is catalytic heterobifunctional molecules that can selectively degrade a protein of interest by recruiting the ubiquitin E3 ligase to the target. PROTACs enhance the ability to drug biological relevant targets through ubiquitylation and degradation based on the proteasome. In the early stage of PROTAC development, permeability assay is crucial for the estimation of the potential molecules.
As an experienced services provider in molecules discovery and research, Profacgen offers several permeability assays service:
Parallel Artificial Membrane Permeability Assay (PAMPA)
PAMPA is used as a model of passive, transcellular permeation, that evaluate permeability over a large pH range for understanding how compounds might be absorbed across the entire gastrointestinal tract. Depending upon the particular lipid and the buffers used, PAMPA assay could be predictive of gastrointestinal tract absorption (PAMPA-GIT), blood-brain barrier permeability (PAMPA-BBB) or transdermal penetration (Skin-PAMPA). PAMPA is considered as easier, faster and less expensive method over other assays in measuring artificial membrane permeability and drug absorption potential.
Caco-2 Permeability Assay
Caco-2 cells are a human colon epithelial cancer cell line and express transporter proteins, efflux proteins, and Phase II conjugation enzymes to model a variety of transcellular pathways as well as metabolic transformation of test substances. When cultured as a monolayer, Caco-2 cells differentiate to form tight junctions between cells to serve as a model of paracellular movement of compounds across the monolayer. In many respects, the Caco-2 cell monolayer is used as a model of human intestinal absorption of drugs and other compounds. The Caco-2 permeability screen is considered to be more representative of human absorption in mimicing processes such as transcellular transport, paracellular transport, and some aspects of efflux and active transport.
Madin - Darby canine kidney cell line (MDCK) Permeability Assay
The MDCK permeability assay is performed to measure test compounds across a monolayer of MDCK cells. With high-monolayer integrity, and morphologic homogeneity, the cells can be seeded on 24- or 96-well plates and then used in high throughput screening. The MDCK cells are easily transfected to express specific transporters and produce robust assay results. Meanwhile, the most concern of using MDCK cells is the presence of endogenous transporters of nonhuman origin, the canine P-glycoprotein (Pgp), which may interfere with permeability and transporter studies and lead to less reliable data.
Advantages of our permeability assay services:
Multiple types assays.
Several technology platforms.
Highly reliable and reproducible results
Quality one-stop PROTACs service
Profacgen promises to work closely with clients, please contact us for more information.
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2. Van Breemen RB, Li Y. (2005). Caco-2 cell permeability assays to measure drug absorption. Expert Opinion on Drug Metabolism & Toxicology, 1(2), 175–185. doi:10.1517/17425255.1.2.175
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