Direct visualization of the real time swelling and collapse of a poly(methacrylic acid) brush using atomic force microscopy

• DOI: 10.1039/b812872c
• Publication Date: 2008-10-28T10:30:15Z
• Authors: Andrew J. Parnell; Simon J. Martin; Richard A. L. Jones; C. Vasilev; Colin J. Crook; Anthony J. Ryan
• Keywords: Force Spectroscopy; Poly(N-isopropylacrylamide)

The reversible height change dynamics of a poly(methacrylic acid) brush, weak polyelectrolyte in response to pH changes, were observed using atomic force microscopy. brush thickness could be repeatably and reversibly switched between 40 nm at 3 120 10.5. swelling collapse transitions took 6 s the AFM measurements, but high resolution spectroscopy measurements showed that can made happen less than second. We conclude time these switches is limited practise by physical taken exchange solvents intrinsic slow brush.