Supplementary Material
“Axial orientation control of zebrafish larvae
using artificial cilia”
by Chia-Yuan Chen*, Tsung-Chun Chang Chien,
Karthick Mani, and Hsiang-Yu Tsai
Department of Mechanical Engineering, National Cheng Kung University
*To whom correspondenceshould be addressed.
*E-mail:; Tel:+886-6-2757575-62169.
The supplementary material includes the following:(a) The bioactivity test; (b) The larva head offsetting test.
(a) The bioactivity test.
To provide information related to the bioactivity of the tested larvae in the axial rotation process, the changes of heart rate at three different steps of the axial rotation operation, namely, before being introduced to, during operation, and after being discharged from the microchannel, are recorded and shown in Fig. S1.Specifically, at the second step the duty cycle was set as zero when the entire body of larva was fully supported by theunderneath artificial ciliainside the microchannel.Although an increase in heart rate is noted at this step of axial rotation, the heart rate at the after being discharged stepresumes to a level similar to that before being introduced to the microchannel data. Given that a typical axial orientation including image capturing takes less than a few seconds, such increase in heart rate for this short time period should have no effects to the development of the tested larvae in the long run.
Fig. S1 Changes of heart rate at three different stages in an orientation control process. A total of 20 larvae data was collected in this measurement treated with the anesthetic dosage of 0.091 mg/mL.
(b) The larva head offsetting test.
Azebrafish offsetting test was conducted to quantify the influence of the opaque property of artificial cilia on the optical access during zebrafish imaging. In this test, six different shifting distances (namely, 120, 220, 440, 610, 720, and 820 µm) away from the tip of the larva were tested at the duty cycle of 80%. The acquired results are shown in Fig. S2. For the shifting distance of 610 µm, where most of the regions of the cranial and thoracic cavities of the larva are visible, the orientation control is still applicable with high accuracy. However, the degree of rotation drops significantly at a larger offset distance such as 820 µm. This result is caused by the fact that a larger effective contact portion of the larva is away from the artificial cilia, and the axial rotation capability of the artificial cilia becomes less effective.
Fig. S2 Results of the zebrafish offsetting test. The symbol D is defined as the distance between the tip of the larva and the first occupied artificial cilium with distances varying from 120 µm (a), 440 µm (b), 610 µm (c), and 820 µm (d). (e): Changes of θfish are plotted against the distance D. A total of six larvae was tested.