Circulating tumor cell capture on a microfluidic chip incorporating both affinity and size

A microfluidic device comprising an array of obstacles coated with antibodies wherein a surface of the device is functionalized with dextran or dextran derivatives.

A microfluidic device comprising an array of obstacles coated with antibodies wherein a surface of the device has a contact angle of less than 15° over at least 10 hours.

-71. (canceled)

A method for capture and release of cells or cell fragments of interest, the method comprising:

• (a) flowing a sample comprising cells or cell fragments of interest on a surface coated with carbohydrate and binding moiety that selectively binds a cell surface marker selectively present on the cells or cell fragments of interest, and (b) using an enzyme that selectively cleaves the carbohydrate or a biotin derivative wherein the biotin derivative competitively releases biotin conjugates, or both, to thereby release the cells or cell fragments of interest from the surface.

-78. (canceled)