Start Date
10-5-2019 10:15 AM
End Date
10-5-2019 11:30 AM
Document Type
Event
Description
Extended research is being conducted in developing soft actuators for biomedical applications. Electroactive polymers, shape-memory alloys, shape-memory polymers and hydraulic or pneumatic actuators that will change the volume of a chamber to induce movement are some of the technologies being used.
Stimuli-responsive hydrogels as actuators is a subject of current research. Stimuli-responsive hydrogels are water absorbent polymer networks that change their volume in response to a given stimulus. The stimulus may be physical (temperature variability), biological (DNA molecules), or chemical (pH variability). Their capability to reverse their response when the stimulus is removed make them suitable to be used in actuation applications.
Thermo-responsive hydrogels are hydrophilic polymer substances that are synthesized into gels from aqueous solution, due to change in ambient temperature. If a temperature above the hydrogel’s lower critical solution temperature (LCST) is applied, the hydrogel will shrink, creating force. This response can be reversed when the temperature gradient is removed.
Recent research focus is on the use of hydrogels actuators in biomedical applications. An implantable device developed by Yang et al, consists of an artificial muscle aimed to mimic the function of the human bladder detrusor. A soft balloon-shaped membrane was fabricated using a thermos-responsive hydrogel with flexible electronics and wireless communication to assist the filling and voiding phase of the bladder.
The need for miniaturization in medical applications has triggered the development of small scale valves to be used in microfluidic circuits to mimic biological systems for testing and rapid screening of drugs or vaccines. In the work of Haefner et al, a highly integrated microfluidic circuit was developed, in which a thermo-responsive hydrogel was used as a microfluidic valve.
Actuation parameters such as response time, force, stroke and reversibility effect are some of the key aspects to consider. The ability to optimize and control actuation performance is another area of interest.
To this effect, various techniques and combinations of polymers and crosslinker materials are being used. As an example, a crosslinker such as synthetic clay (laponite) is being used to enhance the strength of a N-isopropylacrylamide (NIPA).
Hydrogels, as soft actuators, is an emerging topic of interest for biomedical applications. The capability to tune the actuation properties as well as to optimize and control its performance will encourage further developments towards commercialization of such technologies.
DOI
https://doi.org/10.5038/UHOQ9290
Thermo-Responsive Hydrogels as Actuators for Biomedical Applications
Extended research is being conducted in developing soft actuators for biomedical applications. Electroactive polymers, shape-memory alloys, shape-memory polymers and hydraulic or pneumatic actuators that will change the volume of a chamber to induce movement are some of the technologies being used.
Stimuli-responsive hydrogels as actuators is a subject of current research. Stimuli-responsive hydrogels are water absorbent polymer networks that change their volume in response to a given stimulus. The stimulus may be physical (temperature variability), biological (DNA molecules), or chemical (pH variability). Their capability to reverse their response when the stimulus is removed make them suitable to be used in actuation applications.
Thermo-responsive hydrogels are hydrophilic polymer substances that are synthesized into gels from aqueous solution, due to change in ambient temperature. If a temperature above the hydrogel’s lower critical solution temperature (LCST) is applied, the hydrogel will shrink, creating force. This response can be reversed when the temperature gradient is removed.
Recent research focus is on the use of hydrogels actuators in biomedical applications. An implantable device developed by Yang et al, consists of an artificial muscle aimed to mimic the function of the human bladder detrusor. A soft balloon-shaped membrane was fabricated using a thermos-responsive hydrogel with flexible electronics and wireless communication to assist the filling and voiding phase of the bladder.
The need for miniaturization in medical applications has triggered the development of small scale valves to be used in microfluidic circuits to mimic biological systems for testing and rapid screening of drugs or vaccines. In the work of Haefner et al, a highly integrated microfluidic circuit was developed, in which a thermo-responsive hydrogel was used as a microfluidic valve.
Actuation parameters such as response time, force, stroke and reversibility effect are some of the key aspects to consider. The ability to optimize and control actuation performance is another area of interest.
To this effect, various techniques and combinations of polymers and crosslinker materials are being used. As an example, a crosslinker such as synthetic clay (laponite) is being used to enhance the strength of a N-isopropylacrylamide (NIPA).
Hydrogels, as soft actuators, is an emerging topic of interest for biomedical applications. The capability to tune the actuation properties as well as to optimize and control its performance will encourage further developments towards commercialization of such technologies.