Polyelectrolyte brush amplified electroactuation of microcantilevers

被引:103
作者
Zhou, Feng [1 ]
Biesheuvel, P. Maarten [1 ]
Chol, Eun-Young [1 ]
Shu, Wenmiao [1 ]
Poetes, Rosa [2 ]
Steiner, Ullrich [2 ]
Huck, Wilhelm T. S. [1 ]
机构
[1] Univ Cambridge, Melville Lab Polymer Synth, Cambridge CB2 1EW, England
[2] Univ Cambridge, Cavendish Lab, Dept Phys, Cambridge CB3 0HE, England
基金
英国工程与自然科学研究理事会;
关键词
D O I
10.1021/nl073157z
中图分类号
O6 [化学];
学科分类号
0703 ;
摘要
This paper describes the electroactuation of microcantilevers coated on one side with cationic polyelectrolyte brushes. We observed very strong cantilever deflection by alternating the potential on the cantilever between +0.5 and -0.5 V at frequencies up to 0.25 Hz. The actuation resulted from significant increases in the expansive stresses in the polymer brush layer at both negative and positive potentials. However, the deflection at negative bias was significantly larger. We have developed a theoretical framework that correlates conformational changes of the polymer chains in the brush layer with the reorganization of ions due to the potential bias. The model predicts a strong increase in the polymer volume fraction, close to the interface, which results in large expansive stresses that bend the cantilever at negative potentials. The model also predicts that the actuation responds much stronger to negative potentials than positive potentials, as observed in the experiments.
引用
收藏
页码:725 / 730
页数:6
相关论文
共 32 条
[1]   Micro-cantilevers with end-grafted stimulus-responsive polymer brushes for actuation and sensing [J].
Abu-Lail, NI ;
Kaholek, M ;
LaMattina, B ;
Clark, RL ;
Zauscher, S .
SENSORS AND ACTUATORS B-CHEMICAL, 2006, 114 (01) :371-378
[2]  
Bergsjo P, 1997, ACTA OBSTET GYN SCAN, V76, P1
[3]   Electrolyte-induced collapse of a polyelectrolyte brush [J].
Biesalski, M ;
Johannsmann, D ;
Rühe, J .
JOURNAL OF CHEMICAL PHYSICS, 2004, 120 (18) :8807-8814
[4]   Self-consistent field theory of protein adsorption in a non-Gaussian polyelectrolyte brush [J].
Biesheuvel, PM ;
Leermakers, FAM ;
Stuart, MAC .
PHYSICAL REVIEW E, 2006, 73 (01)
[5]   A modified Poisson-Boltzmann model including charge regulation for the adsorption of ionizable polyelectrolytes to charged interfaces, applied to lysozyme adsorption on silica [J].
Biesheuvel, PM ;
van der Veen, M ;
Norde, W .
JOURNAL OF PHYSICAL CHEMISTRY B, 2005, 109 (09) :4172-4180
[6]   Ionizable polyelectrolyte brushes: brush height and electrosteric interaction [J].
Biesheuvel, PM .
JOURNAL OF COLLOID AND INTERFACE SCIENCE, 2004, 275 (01) :97-106
[7]   Synthesis and characterization of polymer brushes on micromechanical cantilevers [J].
Bumbu, GG ;
Kircher, G ;
Wolkenhauer, M ;
Berger, R ;
Gutmann, JS .
MACROMOLECULAR CHEMISTRY AND PHYSICS, 2004, 205 (13) :1713-1720
[8]   Micromechanical cantilever technique: A tool for investigating the swelling of polymer brushes [J].
Bumbu, Gina-Gabriela ;
Wolkenhauer, Markus ;
Kircher, Gunnar ;
Gutmann, Jochen S. ;
Berger, Ruediger .
LANGMUIR, 2007, 23 (04) :2203-2207
[9]   Weighing of biomolecules, single cells and single nanoparticles in fluid [J].
Burg, Thomas P. ;
Godin, Michel ;
Knudsen, Scott M. ;
Shen, Wenjiang ;
Carlson, Greg ;
Foster, John S. ;
Babcock, Ken ;
Manalis, Scott R. .
NATURE, 2007, 446 (7139) :1066-1069
[10]   The effect of [CuI]/[CuII] ratio on the kinetics and conformation of polyelectrolyte brushes by atom transfer radical polymerization [J].
Cheng, Nan ;
Azzaroni, Omar ;
Moya, Sergio ;
Huck, Wilhelm T. S. .
MACROMOLECULAR RAPID COMMUNICATIONS, 2006, 27 (19) :1632-1636