Department of Chemical Engineering (EEBE) and Barcelona Research Center for Multiscale Science and Engineering, Universitat Politècnica de Catalunya, C/Eduard Maristany 10-14, Ed I2, 08019, Barcelona, Spain
Dr. Juan Torras
Department of Chemical Engineering (EEBE) and Barcelona Research Center for Multiscale Science and Engineering, Universitat Politècnica de Catalunya, C/Eduard Maristany 10-14, Ed I2, 08019, Barcelona, Spain
Porous biodegradable scaffolds provide a physical substrate for cells allowing them to attach, proliferate and guide the formation of new tissues. A variety of techniques have been developed to fabricate tissue engineering (TE) scaffolds, among them the most relevant is the thermally-induced phase separation (TIPS). This technique has been widely used in recent years to fabricate three-dimensional (3D) TE scaffolds. Low production cost, simple experimental procedure and easy processability together with the capability to produce highly porous scaffolds with controllable architecture justify the popularity of TIPS. This paper provides a general overview of the TIPS methodology applied for the preparation of 3D porous TE scaffolds. The recent advances in the fabrication of porous scaffolds through this technique, in terms of technology and material selection, have been reviewed. In addition, how properties can be effectively modified to serve as ideal substrates for specific target cells has been specifically addressed. Additionally, examples are offered with respect to changes of TIPS procedure parameters, the combination of TIPS with other techniques and innovations in polymer or filler selection.
Temperature‐sensitive (thermosensitive) hydrogels, which are part of the family of stimulus‐sensitive hydrogels, consist of water‐filled polymer networks that display a temperature‐dependent degree of swelling. Thermosensitive hydrogels, which can undergo phase transition or swell/de‐swell as temperature changes, have great potential in various technological and biomedical purposes for a number of reasons: their temperature response is reversible, hydrogels are stable and easy to prepare, they can be biocompatible and also be suitably combined with other organic and inorganic materials, resulting in new materials with outstanding properties. Among thermosensitive hydrogels poly(N‐isopropylacrylamide) (PNIPAAm) is the most extensively studied because it brings together the best properties of these materials. Consequently, in the past few years, a wide number of applications and new chemical processes to prepare PNIPAAm and their derivatives are being proposed. The objective of this review is to summarize the fundamentals of thermosensitive hydrogels and recent advances in preparation and both technological and biomedical applications of thermosensitive hydrogel, with a special focus on PNIPAAm and their derivatives. Special attention has been given to the discussion of challenges and future research perspectives based on new horizons not yet considered.
3 July 2012 in The Journal of Physical Chemistry A
Biosensors are increasingly taking a more active role in health science. The current needs for the constant monitoring of biomedical signals, as well as the growing spending on public health, make it necessary to search for materials with a combination of properties such as biocompatibility, electroactivity, resorption, and high selectivity to certain bioanalytes. Conducting polymer hydrogels seem to be a very promising materials, since they present many of the necessary properties to be used as biosensors. Furthermore, their properties can be shaped and enhanced by designing conductive polymer hydrogel-based composites with more specific functionalities depending on the end application. This work will review the recent state of the art of different biological hydrogels for biosensor applications, discuss the properties of the different components alone and in combination, and reveal their high potential as candidate materials in the fabrication of all-organic diagnostic, wearable, and implantable sensor devices.
19 September 2014 in The Journal of Physical Chemistry B