University of Washington HomepageUniversity of Washington Electrical Engineering Department HomepageMEMS Laboratory Homepage

Projects Archive

Thermally Responsive ppNIPAM Thin Films - Protein and Cell Arrays on Thermally Responsive Polymers


Team Members

Yanbing Wang, Yael Hanein, Ashutosh Shastry, Denice Denton, Karl F. Böhringer, Xuanhong Chen, Buddy Ratner (Bioengineering)



Programmable surface chemistry has been achieved by depositing a temperature sensitive polymer onto arrays of micro-fabricated metallic heaters. Activating a single heater causes a localized change in the device surface chemistry from non-fouling to fouling in an aqueous environment. Two types of proteins and two types of cells were used to demonstrate localized immobilization of proteins and cells on such surfaces. These experiments show, for the first time, selective cell attachments on thermally responsive polymer controlled by a micro heater array. It suggests a new approach to realize proteomic chips and cell chips.


b a

Figure 1: . Schematic description of ppNIPAM devices. (a) Devices consist of micro-heaters on a glass slide coated with ppNIPAM. (b) Active heater (dark) turns the surface fouling. Selective protein/cell adsorption occurs exclusively on heated areas. Temperature sensitive paint was used to characterize the temperature profile. (c) A second adsorption step with different protein/cell solution on a different heater.

Figure 2: Two steps of cell attachments on the top and bottom heater, respectively. (a) Bright field mode and (b) Fluorescence mode.


Selected Publications

A complete list of our publications (many of them available online) can be found here.