Motion-based pH sensing using spindle-like micromotors
micromotor, autonomous movement, self-propelling, motion-based sensing
In this study, we report a spindle-like micromotor. This device, which isfabricated using a one-step electrospinning method, consists of biodegradablepolycaprolactone and an anionic surfactant. Intriguingly, not only can theresulting micromotor move autonomously on the surface of water for a longperiod of time (~40 min) due to the Marangoni effect, but it also exhibits a pHsensing behavior due to variations in the surface tension caused by the releaseof surfactant under different pH conditions. More interestingly, we reveal thatthe motion-based pH sensing property is size-dependent, with smaller structuresexhibiting a higher sensitivity. In addition, since polycaprolactone is a biodegradablematerial, the micromotor described in this study can be easily degradedin solution. Hence, features such as one-step fabrication, motion readout, andbiodegradability render this micromotor an attractive candidate for sensingapplications.
Tsinghua University Press
Limei Liu,Yonggang Dong,Yunyu Sun,Mei Liu,Yajun Su,Hui Zhang,Bin Dong, Motion-based pH sensing using spindle-like micromotors. NanoRes.2016, 9(5): 1310–1318