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Fluorescence-based assessment of plasma-induced hydrophilicity in microfluidic devices via Nile Red adsorption and depletion.

ABSTRACT: We present a simple method, called fluorescence-based assessment of plasma-induced hydrophilicity (FAPH), that enables spatial mapping of the local hydrophilicity of surfaces normally inaccessible by traditional contact angle measurement techniques. The method leverages the change in fluorescence of a dye, Nile Red, which is adsorbed on an oxygen plasma-treated surface, and its correlation with the contact angle of water. Using FAPH, we explored the effect of microchannel geometries on the penetration distance of oxygen plasma into a microchannel and found that entrance effects prevent uniform treatment. We showed that these variations have a significant impact on cell culture, and thus the design of cell-based microfluidic assays must consider this phenomenon to obtain repeatable and homogeneous results.

SUBMITTER: Guckenberger DJ

PROVIDER: S-EPMC4144722 | biostudies-literature | 2014 Aug

REPOSITORIES: biostudies-literature

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Fluorescence-based assessment of plasma-induced hydrophilicity in microfluidic devices via Nile Red adsorption and depletion.

Guckenberger David J DJ Berthier Erwin E Young Edmond W K EW Beebe David J DJ

Analytical chemistry 20140717 15

We present a simple method, called fluorescence-based assessment of plasma-induced hydrophilicity (FAPH), that enables spatial mapping of the local hydrophilicity of surfaces normally inaccessible by traditional contact angle measurement techniques. The method leverages the change in fluorescence of a dye, Nile Red, which is adsorbed on an oxygen plasma-treated surface, and its correlation with the contact angle of water. Using FAPH, we explored the effect of microchannel geometries on the penet ...[more]

PMID: 25032783

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Dataset Information

Fluorescence-based assessment of plasma-induced hydrophilicity in microfluidic devices via Nile Red adsorption and depletion.

Publications

Fluorescence-based assessment of plasma-induced hydrophilicity in microfluidic devices via Nile Red adsorption and depletion.

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