Polymer Gels pp 341-359 | Cite as

Thermo-intelligent Injectable Implants: Intricate Mechanisms and Therapeutic Applications

  • Pradeep Kumar
  • Yahya E. Choonara
  • Viness Pillay
Part of the Gels Horizons: From Science to Smart Materials book series (GHFSSM)


The importance, influence and effectiveness of thermo-intelligent systems are evident from the fact that thermo-induced bioactive and biointeractive therapy features among the only two stimuli-responsive systems undergoing clinical trials. This chapter provides a detailed mechanistic account of the most widely used thermosensitive polymers such as chitosan-β-glycerophosphate, poly(ethylene glycol)-g-chitosan, methylcellulose, Pluronics, amphiphilic poly(ethylene glycol)/polyhydroxy acids block copolymers and poly(N-isopropylacrylamide). The inherent thermogelling mechanisms governing these specialized injectable implants include, but not limited to, attractive and repulsive interchain interactions, formation of dehydrated hydrophobic architectures, steep decline in the mobility of the polymeric side chains, creation of reversible crosslinking loci, creation of highly stabilized hydrophobically crosslinked networks, lattice restructuring, decrease in critical micelle concentration, advent of frictional forces between the copolymer micelles, entropy change from gauche state to antistate, increase in the volume fraction of micelles and chain collapse before aggregation followed by polymer scattering. Additionally, the chapter evaluates the behaviour and integration of injectable thermogelling systems towards the fabrication and development of therapeutic paradigms. Furthermore, the combinatorial stigmergy of multiplatform multi-responsive conjugated systems is proposed as an alternative and futuristic approach.


Thermoresponsive Thermosensitive Thermogels Hydrogels Injectable Thermogelation mechanism Drug delivery Polymers Implant 


Financial and Competing Interests Disclosure

The authors have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending or royalties. No writing assistance was utilized in the production of this manuscript.


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Copyright information

© Springer Nature Singapore Pte Ltd. 2018

Authors and Affiliations

  • Pradeep Kumar
    • 1
  • Yahya E. Choonara
    • 1
  • Viness Pillay
    • 1
  1. 1.Wits Advanced Drug Delivery Platform Research Unit, Department of Pharmacy and Pharmacology, Faculty of Health SciencesSchool of Therapeutic Sciences, University of the WitwatersrandJohannesburgSouth Africa

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