School of Electrical Engineering, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon 34141, Republic of Korea.
KAIST Institute for Health Science and Technology (KIHST), Daejeon 34141, Republic of Korea.
ACS Appl Mater Interfaces. 2021 Dec 1;13(47):55827-55839. doi: 10.1021/acsami.1c16735. Epub 2021 Nov 16.
There is an increasing interest in developing next-generation wearable ultrasound patch systems because of their wide range of applications, such as home healthcare systems and continuous monitoring systems for physiological conditions. A wearable ultrasound patch system requires a stable interface to the skin, an ultrasound coupling medium, a flexible transducer array, and miniaturized operating circuitries. In this study, we proposed a patch composed of calcium (Ca)-modified silk, which serves as both a stable interface and a coupling medium for ultrasound transducer arrays. The Ca-modified silk patch provided not only a stable and conformal interface between the epidermal ultrasound transducer and human skin with high adhesion but also offered acoustic impedance close to that of human skin. The Ca-modified silk patch was flexible and stretchable (∼400% strain) and could be attached to various materials. In addition, because the acoustic impedance of the Ca-modified silk patch was 2.15 MRayl, which was similar to that of human skin (1.99 MRayl), the ultrasound transmission loss of the proposed patch was relatively low (∼0.002 dB). We also verified the use of the Ca-modified silk patch in various ultrasound applications, including ultrasound imaging, ultrasound heating, and transcranial ultrasound stimulation for neuromodulation. The comparable performance of the Ca-modified patch to that of a commercial ultrasound gel and its durability against various environmental conditions confirmed that the Ca-modified silk patch could be a promising candidate as a coupling medium for next-generation ultrasound patch systems.
由于其广泛的应用，如家庭医疗保健系统和生理条件的连续监测系统，人们对开发下一代可穿戴超声贴片系统越来越感兴趣。可穿戴超声贴片系统需要与皮肤稳定的接口、超声耦合介质、柔性换能器阵列和小型化的操作电路。在本研究中，我们提出了一种由钙（Ca）改性丝组成的贴片，它既可以作为稳定的接口，也可以作为超声换能器阵列的耦合介质。Ca 改性丝贴片不仅为表皮超声换能器和人提供了稳定和顺应的接口，而且与人体皮肤具有高附着力，还提供了接近人体皮肤的声阻抗。Ca 改性丝贴片具有柔韧性和拉伸性（∼400%应变），可以附着在各种材料上。此外，由于 Ca 改性丝贴片的声阻抗为 2.15 MRayl，与人体皮肤的声阻抗（1.99 MRayl）相似，因此该贴片的超声传输损耗相对较低（∼0.002 dB）。我们还验证了 Ca 改性丝贴片在各种超声应用中的使用，包括超声成像、超声加热和经颅超声刺激用于神经调节。Ca 改性贴片与商用超声凝胶的性能相当，并且能够耐受各种环境条件，这证实了 Ca 改性丝贴片作为下一代超声贴片系统的耦合介质具有广阔的应用前景。
