Monitoring of living cell attachment and spreading using reverse symmetry waveguide sensing

Abstract

The effect of the attachment and spreading of living cells on the modes of a grating coupled reverse symmetry waveguide sensor is investigated in real time. The reverse symmetry design has an increased probing depth into the sample making it well suited for the monitoring of cell morphology. As a result, significant changes in the incoupling peak height and peak shape were observed during cell attachment and spreading. It is suggested that the area under the incoupling peaks reflects the initial cell attachment process, while the mean peak position is mostly governed by the spreading of the cells.

Microfluidic channels laser-cut in thin double-sided tapes: Cost-effective biocompatible fluidics in minutes from design to final integration with optical biochips

“…For interrogating the waveguide sensors and recording the effective refractive index changes of the waveguide modes a benchtop GCI setup [11] and a BIOS OWLS system (Microvacuum Ltd., Hungary) [14] were used. Before integration, the sensor chips were cleaned with chromsulfuric acid according to published protocols [15,16] and dried with a stream of clean nitrogen gas.…”

Sample handling in surface sensitive chemical and biological sensing: A practical review of basic fluidics and analyte transport

“…In contrast to the desirable fast, yet gentle and controllable sample exchange, cumbersome pipetting from a closed cuvette implies the relatively uncontrolled removal of only a portion of the bathing medium. In addition, when the cuvette is mounted on the rotating goniometer of an integrated optical scanner (incoupling configuration [16]) the scanning has to be stopped to perform any manipulation in the sample volume of the closed cuvette and, therefore, typically for tens of seconds following sample 28 addition the response cannot be monitored. In an OWLS device without moving parts, such as the outcoupling configuration [17] or one of the various kinds of interferometry [7,17], the measurement would not have to be stopped, although there might be some optical perturbation due to fluid movements.…”

“…label-free detection with a typical temporal resolution of 10-20 s, which makes it an ideal research tool in several fields, including the online monitoring of protein adsorption [19,20,21,22], bacterial [23,24] and mammalian cell adhesion [25,26,27,28,29,30], supported lipid-bilayer deposition [31,32], polyelectrolyte multilayer build-up [33,34,35], nanoparticle surface adhesion and assembly [36,37], and receptor-ligand interactions [38,39].…”

“…of cells are monitored [14,25,26,28,30]. Depending on the aim of the investigation, cellular assays on a biosensor may take up to hours or days, and the fewer disturbances to the system during the measurement the better.…”

Label-free optical monitoring of surface adhesion of extracellular vesicles by grating coupled interferometry

“…In contrast to SPR, using waveguides the penetration depth can be easily tuned through waveguide design, matching in this way the sensing depth to the size of the adsorbed object. 5,6,7 An emerging area where the label-free surface sensitive sensors could be exploited is the interaction of extracellular vesicles (EVs) with model surfaces, biomolecules, polymers and receptors.…”