Join us for The Sir Martin Wood Prize Lecture where we will hear from Prof. Takamasa Sakai from the Department of Bioengineering, The University of Tokyo.
Prof. Sakai will discuss his research on ‘Tetra Gels’, a structurally homogenous hydrogel with limited degrees of freedom, eliminating several types of heterogeneity intrinsic to conventional gels.
In this talk, Prof Sakai will discuss their approach to synthesizing these hydrogels and how they may be used in the future for both fundamental studies of hydrogels and in use in medical applications.
The Sir Martin Wood Prize, named after the founder of Oxford Instruments, was established in 1999 with the objective of giving recognition and encouragement to young scientists in Japan. The Prize is sponsored by the British company Oxford Instruments plc.
The Sir Martin Wood Prize is awarded annually to a scientist, younger than 45, who has achieved remarkable results in condensed matter science at a university or research institute in Japan. Condensed matter science includes condensed matter physics, inorganic-organic chemistry, material science and surface-interface physics.
Abstract:
A hydrogel (hereafter referred to as a “gel”) is a material in which a three-dimensional polymer network absorbs and swells with water. Gels are familiar materials found in dairy items such as diapers, soft contact lenses, and food products. Moreover, since the soft tissues of living organisms have similar structures and compositions, gels have attracted attention both as models for biological tissues and as candidates for medical applications. A precise understanding of the relationship between network structure and physical properties is the starting point for achieving these goals and holds a central position in gel science. However, the network structure of a gel is inherently heterogeneous, and even the most advanced microscopy techniques cannot visualize it, making it impossible to quantitatively represent the network structure. Consequently, experimental verification of theoretical predictions for the structure–property relationship of gels has been challenging, and conventional theories have been treated as only coarse approximations.
In response, we conceived that synthesizing a series of gels with suppressed heterogeneity—previously considered unavoidable—would be the starting point for a fundamental understanding of gels. Based on this idea, we pioneered the design and development of structurally homogeneous gels, termed Tetra Gels. Tetra Gels are synthesized from two types of four-armed prepolymers, each bearing mutually reactive functional groups. This molecular design limits the degrees of freedom of the resulting network, thereby eliminating, in principle, several types of heterogeneity intrinsic to conventional gels. Furthermore, the Tetra Gel family can be defined by three independent control parameters: (i) the molecular weight of the prepolymers, (ii) the prepolymer concentration, and (iii) the extent of connectivity between prepolymers. By systematically tuning these parameters and comprehensively measuring the physical properties of the resulting gels, we succeeded in describing various gel properties as functions of the three independent variables. Through the promotion of this experimentally grounded and quantitative approach—what we term “Precision Gel Science”—we have discovered phenomena such as negative energy elasticity hidden in gel elasticity, a universal equation of state of osmotic pressure, and the quantitative characterization of network inhomogeneity. In the presentation, these findings will be introduced and discussed.
In parallel with these fundamental studies, we are also developing medical hydrogels using Tetra Gel as a platform. Because the structure–property relationships of Tetra Gels are formulated, prototyping can be achieved extremely rapidly—within as little as one week. Tetra Gels can be designed to solidify at a desired time, exhibit targeted mechanical properties, and degrade at a controlled rate. Using this rational design approach, we are developing medical gels such as hemostatic agents, anti-adhesion materials, and scaffolds for regenerative medicine. This lecture will also present the current status of these translational research efforts.
This lecture will be taking place in the Sir William Henry Bragg Building Lecture Theatre, LT 2.37 (located on the 2nd floor).
Lunch will be provided after the seminar room GR18 (located on the ground floor).
Location
Sir William Henry Bragg Building, Lecture Theatre 2.37
June 4 2026
