Sulfo-Cy3 Dextran (MW 100000)

TEER measures electrical resistance across epithelial or endothelial monolayers cultured on permeable supports, and the readout reflects ionic conductance through the cell barrier, especially the paracellular pathway regulated by junctional integrity. TEER can be measured without destroying the monolayer and is commonly used before or during transport, permeability, barrier-disruption, and barrier-maturation experiments. TEER values are influenced by biological maturation and technical conditions; reported factors include temperature, medium formulation, passage number, electrode geometry, membrane properties, and junctional length during early monolayer maturation. Therefore, TEER should be interpreted with blank-insert subtraction, area normalization, repeated readings, and, when possible, orthogonal barrier readouts such as FITC-dextran flux or tight-junction staining.

Bioluminescent and fluorescent imaging xenograft models use tumor cells engineered to express optical reporters so tumor engraftment, growth, dissemination, and treatment response can be monitored longitudinally in living animals and validated ex vivo. Bioluminescence imaging usually measures luciferase activity after substrate administration and is commonly used as a surrogate for viable reporter-expressing tumor burden, while fluorescence imaging measures reporter or probe emission and can support tumor localization, ex vivo confirmation, or complementary multimodal analysis.