Photophobic and phototropic movement of a self-oscillating gel

Abstract

A photosensitive self-oscillating gel that incorporates the Belousov-Zhabotinsky reaction can undergo rhythmic mechanical oscillations. We exploit the dependence of the oscillation frequency on light intensity to generate both photophobic and phototropic movement of the gel under differential illumination. Our findings may be used in designing intelligent sensors that can execute biomimetic behaviours.

Using light to control the interactions between self-rotating assemblies of active gels

“…The gLSM has proven to be a powerful approach for predicting the behavior of these self-oscillating gels [8,14,16e20]. Of particular relevance here, we predicted that rectangular-shaped BZ gels on a surface would undergo selfpropelled, directed motion in the presence of light [21,22]; these predictions were recently confirmed experimentally [23]. We have augmented the gLSM [24] by incorporating the evolution of the activator concentration, u, outside the gels and within the external fluid:…”

Designing biomimetic reactive polymer gels

“…The next challenge is controlling the formation and rotation of two or more pinwheels. Notably, the BZ reaction is photosensitive [44] and hence, light can be used to regulate the movement of these gels [36,37,40,41,45]. Our very recent studies on the eight gels in Fig.…”

Modeling Stimuli-Induced Reconfiguration and Directed Motion of Responsive Gels

“…Epstein et al 48 considered a freely sliding BZ gel confined in a capillary tube; when one end of the tube was illuminated with light of a higher intensity than the other end of the tube, the gel displayed negative phototaxis, moving toward the darker region provided that, for the selected intensities, the frequency of oscillations is higher in the darker than in the brighter region. 48 …”