Stimuli-induced changes and their applications

In the biomedical community, materials that are responsive to external stimuli play an important role because of the varying conditions that are found throughout the in vivo enviromnent. In this section, many of the responsive properties of polyelectrolytes and zwitterionic polymers will be discussed, and examples of applications for each responsive property will be provided if they have been demonstrated. If not, proposed applications are given. The subsections are ordered based on the relative level of activity in the scientific community to develop and utilize each stimulus for biomedical purposes. 

As discussed above, changes in the charge state of the polymer also result in changes in the conformation of the polymer. This responsive swelling behavior has been demonstrated in both hydrogel (Dogu, Kilic, Okay, 2009 Xu et al., 2008) and 

Switchable and Responsive Surfaces and Materials for Biomedical Applications 

This figure is reprinted from Mi et al. (2010) with permission. Copyright 2010 Elsevier. 

This allows the specific attachment of proteins or other signaling molecules within a nonfouling or protein-resistant background in CB polymer systems and polyampholyte copolymer systems with overall charge neutrality. This has been demonstrated in biosensor-based platforms with both chemistries, as a platform for highly sensitive and selective diagnostics (Tab Bernards, 2012 Vaisocherova et al., 2008, 

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