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Title: Switchable Hydrophobic-Hydrophilic Surfaces

Technical Report ·
DOI:https://doi.org/10.2172/806703· OSTI ID:806703

Tethered films of poly n-isopropylacrylamide (PNIPAM) films have been developed as materials that can be used to switch the chemistry of a surface in response to thermal activation. In water, PNIPAM exhibits a thermally-activated phase transition that is accompanied by significant changes in polymer volume, water contact angle, and protein adsorption characteristics. New synthesis routes have been developed to prepare PNIPAM films via in-situ polymerization on self-assembled monolayers. Swelling transitions in tethered films have been characterized using a wide range of techniques including surface plasmon resonance, attenuated total reflectance infrared spectroscopy, interfacial force microscopy, neutron reflectivity, and theoretical modeling. PNIPAM films have been deployed in integrated microfluidic systems. Switchable PNIPAM films have been investigated for a range of fluidic applications including fluid pumping via surface energy switching and switchable protein traps for pre-concentrating and separating proteins on microfluidic chips.

Research Organization:
Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Sandia National Lab. (SNL-CA), Livermore, CA (United States)
Sponsoring Organization:
US Department of Energy (US)
DOE Contract Number:
AC04-94AL85000
OSTI ID:
806703
Report Number(s):
SAND2002-3870; TRN: US0301391
Resource Relation:
Other Information: PBD: 1 Dec 2002
Country of Publication:
United States
Language:
English