alexa stimuli responsive polymers| stimuli for biomedical applications
ISSN: 2161-0398
Journal of Physical Chemistry & Biophysics
Like us on:
Make the best use of Scientific Research and information from our 700+ peer reviewed, Open Access Journals that operates with the help of 50,000+ Editorial Board Members and esteemed reviewers and 1000+ Scientific associations in Medical, Clinical, Pharmaceutical, Engineering, Technology and Management Fields.
Meet Inspiring Speakers and Experts at our 3000+ Global Conferenceseries Events with over 600+ Conferences, 1200+ Symposiums and 1200+ Workshops on
Medical, Pharma, Engineering, Science, Technology and Business

Stimuli Responsive Polymers for Biophysical Applications

Ajay Vidyasagar*
Department of Chemical Engineering and Materials Science, University of Minnesota, USA
Corresponding Author : Ajay Vidyasagar
Department of Chemical Engineering and Materials Science
University of Minnesota, 421 Washington ave SE
Minneapolis, MN – 55455, USA
E-mail: [email protected]
Received December 05, 2013; Accepted December 08, 2013; Published December 11, 2013
Citation: Vidyasagar A (2013) Stimuli Responsive Polymers for Biophysical Applications. J Phys Chem Biophys 3:e116. doi:10.4172/2161-0398.1000e116
Copyright: © 2013 Vidyasagar A. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Visit for more related articles at Journal of Physical Chemistry & Biophysics

Our quest to mimic biological functions using synthetic routes is an ongoing challenge that has shown immense potential in several biomedical applications. The potential of utilizing the smart behaviour of responsive polymers is wide open and has attracted the attentions of several leadingresearchers in the last two decades. Potential applications include and but limited are in drug delivery [1,2], biosensors [3], tissue engineering [4] and actuators [5]. The design of novel systems has to meet several criteria in order to become effective biomedical tools. They must be relativelysimple to synthesize and deliver in vivo, exhibit specific responses tuned to targeted event ofinterest, be biocompatible/ biodegradable and be cost effective.
Polymers that respond to specific stimuli by undergoing conformational or phase changes are ofparticular interest. The most widely studied synthetic smart responsive polymer is poly(Nisopropylacrylamide)( poly(NIPAAm)) which undergoes a reversible transition from a soluble hydrophilic coil state to an insoluble hydrophobic globule state at approximately 320C in aqueous solutions [6-8]. The temperature at which the transition occurs is called the lower critical solution temperature (LCST), below which the polymer segments and solvent molecules co-exist as a single homogeneous phase with favourable free energy of mixing (G<0). Above LCST, demixing occurs between the polymer segments and solvent molecules resulting in an increase in free energy (G>0) due to phase separation. Other thermoresponsive polymers include poly(diethylacrylamide) (poly(DEAAm)) [9], Poly(N-vinylcaprolactone) (Poly(VCL) [10] and poly(N-(dl)-(1-hydroxymethyl) propylmethacrylamide) (poly(dl)- HMPMA) [11], which all have a LCST in the range 32-370C. The close proximity of the transitions to physiological temperatures makes these polymers ideal for several biological applications.
Like temperature, pH is an important environmental stimuli for biomedical applications. Some ofthe common pH responsive polymers like poly(acrylic acid) (PAA), Chitosan, poly(L-lysine) (PL),and poly(ethylene imine) (PEI) [12-14]. There are drastic changes to the pH environment from the gastrointestinal tract (pH-1.3) to the stomach (pH 5-8). The presence of ionization groups likeamino or carboxyl groups offers pH sensitivity making them very desirable. Researcher’s usually combine thermo and pH responsiveness in order to design multi-responsive polymer systems. For example, NIPAAm copolymerized with acrylic acid and spirobenzopyran, provides temperature, pH and photo responsiveness [15]. In another example, colloidal particles have beenused to design adhesion platforms for protein and specific cell types [16]. The possibilities of designing multiresponsive polymers are endless. There are however certain challenges owing tospatial restrictions that may occur especially at surfaces and interfaces of polymer gels or other similar systems. Another emerging area is to take advantage of biological compatibility with the synthetic versatility by designing hybrid polymers. For instance, poly(ethylene glycol) (PEG)segments have been conjugated with proteins to enhance biological activity [17]. In another example, poly(NIPAAm) conjugated to streptavidin engineered to present a thiol functionality by introducing a cysteine residue near a Biotin site. It was seen that Biotin reacts strongly by binding with the polymer-streptavidin conjugate below the LCST (<320C) of NIPAAm. No evidence ofsuch strong binding was seen above the LCST, owing to the phase transition of the bioconjugate [18].
The design of stimuli responsive polymers in relatively a new and emerging area with infinite possibilities that need to be explored. The wide range of potential applications in biomedical fields such as in drug delivery, tissue engineering, surface activation, sensors, actuators etc. is only scratching the surface. Polymers that respond to single stimuli like temperature or pH alone are unlikely to find widespread applications. There is a need to fabricate materials that are truly smart with fine control over molecular weight, composition, and block architecture, incorporating multiple functionality within the polymer structures. The design of hybrid polymers that marry synthetic and biological features is the future of smart polymers for future biomedical applications. It is also imperative that researches focus on key areas like understanding the underlying molecular mechanism of designing better systems, improving mechanical robustness, improving specificity, and solving spatial constraints associated with confined systems.

Select your language of interest to view the total content in your interested language
Post your comment

Share This Article

Recommended Conferences

  • 2nd International Conference on Physics
    Aug 28-30, 2017 Brussels, Belgium
  • 5th Global Chemistry Congress
    September 04-06, 2017 London, UK
  • 3rd World Chemistry Conference
    September 11-12, 2017 Dallas, USA
  • Global Conference on Physical Chemistry
    September 18-19, 2017 Dublin, Ireland
  • 2nd International Conference on Applied Chemistry  
    October 16-17, 2017 Toronto, Canada

Article Usage

  • Total views: 11664
  • [From(publication date):
    December-2013 - Aug 19, 2017]
  • Breakdown by view type
  • HTML page views : 7857
  • PDF downloads :3807

Post your comment

captcha   Reload  Can't read the image? click here to refresh

Peer Reviewed Journals
Make the best use of Scientific Research and information from our 700 + peer reviewed, Open Access Journals
International Conferences 2017-18
Meet Inspiring Speakers and Experts at our 3000+ Global Annual Meetings

Contact Us

© 2008-2017 OMICS International - Open Access Publisher. Best viewed in Mozilla Firefox | Google Chrome | Above IE 7.0 version