APTS-labeled dextran ladder: A novel tool to characterize cell layer tightness

Validation of in vitro cell culture models of the blood–brain barrier: Tightness characterization of two promising cell lines

“…Dextrans (average molecular weight = 5779 g/mol, MW/MN = 2.39) were labeled with APTS by reductive amination and analyzed by capillary electrophoresis (CE) as reported by Neuhaus et al10 The total fluorescence of APTS‐labeled dextran was determined by using a microplate reader (polarstar galaxy, BMG Labtech, Offenburg, Germany) at an excitation wave length of 485 nm and an emission filter at 520 nm. CE separations were performed at 25°C using a P/ACE 5500 system with a LIF detector (Beckman Instruments, Fullerton, CA), Ar laser (exc.…”

“…After derivatization, the fraction pattern was checked prior to first application for transport studies. Validation data were reported previously 10…”

“…Several studies using different types of molecules with different molecular weights were carried out for basic tightness characterizations,6–9 but no method for measuring a permeability pattern based on molecular weight of similar, oligomeric molecules had existed until now. We have developed a dextran ladder, where dextran was labeled with fluorescent APTS 10. With this tool a molecular weight dependent permeability pattern ranging from free APTS to APTS‐dextran consisting of 35 glucose units with a resolution of one glucose molecule can be obtained 11.…”

Novel DNA fluorescence probes based on N-[5-(11-functionalised-undecylamino)-9H-benzo[a]phenoxazin-9-ylidene]propan-1-aminium chlorides: synthesis and photophysical studies

“…In recent years, the development of fluorescent probes, which offer a wealth of information in various fields, has attracted the interest of researchers. [1][2][3] The strong influence of the surrounding medium on fluorescence emission, has led to fluorescent molecules being used as probes for the investigation of physicochemical, biochemical and biological systems. The solubility of the probes and the resulting specific interactions that can be established with the system to be probed are governed by their chemical nature; the hydrophobic, hydrophilic or amphiphilic character of the probe is essential in this regard.…”

A Novel Tool to Characterize Paracellular Transport: The APTS–Dextran Ladder

“…After derivatization, the fraction pattern was checked prior to first application for transport studies. Validation data were reported (33).…”