What is Caco-2 permeability?
Caco-2 permeability assay to investigate intestinal permeability. Cyprotex’s Caco-2 permeability assay uses an established method that measures the rate of flux of a compound across polarised Caco-2 cell monolayers and from which the data generated can be used to predict in vivo absorption of drugs.
What is Papp permeability?
Apparent permeability (Papp) based on the flux of a molecule across a barrier of known molecular weight is a measure of the integrity of the in vitro BBB model.
Why Caco-2 cells are used?
The Caco-2 cells isolated from human colorectal adenocarcinoma are widely used to screen for absorption rate of new compounds in the initial stage of drug discovery.
How do you calculate apparent permeability coefficient?
The formula to calculate apparent permeability or P aap= (dQ/dt)x 1/AC, where dQ/dt is change in concentration / change in time at steady state and A is the growth area and C is the initial conentration in apical chamber. is this formula correct.
How can you increase the permeability of a drug?
The approaches include traditional methods such as prodrugs, permeation enhancers, ion-pairing, etc., as well as relatively modern approaches such as nanoencapsulation and nanosizing. The most recent approaches include a combination/hybridization of one or more traditional approaches to improve drug permeability.
What is a good efflux ratio?
The use of animal or in vitro permeability test methods is recommended only for drug substances that are transported by passive mechanisms (efflux ratio of the test drug should be < 2).”
How do you differentiate Caco-2 cells?
Standard methods used to differentiate Caco-2 cells involve seeding them on culture inserts fitted with polycarbonate filters, and allowing spontaneous differentiation to proceed for two to three weeks in culture medium containing 10% or 20% foetal bovine serum (FBS) in both the apical (AP) and basolateral (BL) …
How do Caco-2 cells grow?
The cells should be kept at 37 °C in a humidified atmosphere containing 5 % CO2. For propagation in culture flasks, Caco-2 cells are seeded in a concentration of 105 cells/cm2. Medium should be changed every 3 days. At 80 % confluence, typically after 4–5 days, the cells are split 1:10 before further cultivation.
What is apparent permeability coefficient?
Apparent permeability coefficients (Papp) were calculated from the equation where ΔQ/Δtis the steady-state flux (mol/s), C0 is the initial concentration in the donor chamber at each time interval (mol/mL), and A is the surface area of the filter (cm2).
What affects permeability?
The permeability of a membrane is affected by temperature, the types of solutes present and the level of cell hydration. Increasing temperature makes the membrane more unstable and very fluid.
What are permeation enhancers?
Chemical permeation enhancers (CPEs) are molecules that interact with the constituents of skin’s outermost and rate limiting layer stratum corneum (SC), and increase its permeability. Designing and testing of new CPEs is a resource intensive task, thus limiting the rate of discovery of new CPEs.
How long does it take for Caco-2 cells to adhere?
about 48h
when Caco-2 cells are subcultured,it takes about 48h to attach substrate.It may takes more time for thawing cells. 2. the seed density is important for Caco-2 cells to form a nice monolayer.
What is efflux ratio?
Efflux ratio (ER) is defined as the ratio of flux from the basal to apical compartment to that from apical to basal compartment in the cell monolayer.
What 3 factors affect the permeability of cell membranes?
The permeability of a membrane is affected by temperature, the types of solutes present and the level of cell hydration.
What is Caco-2 cell permeability?
Caco-2 cell permeability assays to measure drug absorption Caco-2 cells are a human colon epithelial cancer cell line used as a model of human intestinal absorption of drugs and other compounds.
What affects the predictive ability of Caco-2 models?
The predictive ability of the models, although rather good for a preliminary study, is somewhat affected by the poor precision of the experimental Caco-2 measurements. Finally, the generalization ability of one model was checked on an external test set not derived from the data sets used to build the models.
What is the function of CaCO 2 cells?
In addition, Caco-2 cells 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. In many respects, the Caco-2 cell monolayer mimics the human intestinal epithelium.
How are Caco-2 cell monolayers cultured?
Caco-2 cell monolayers are usually cultured on semipermeable plastic supports that may be fitted into the wells of multi-well culture plates. Test compounds are then added to either the apical or basolateral sides of the monolayer.