Maione Emiliano, Shung K Kirk, Meyer Richard J, Hughes Jack W, Newnham Robert E, Smith Nadine Barrie
Encapsulation Systems Inc., Broomall, PA. 19008, USA.
IEEE Trans Ultrason Ferroelectr Freq Control. 2002 Oct;49(10):1430-6. doi: 10.1109/tuffc.2002.1041084.
For application in a portable transdermal drug-delivery system, novel transducers have been designed to enhance insulin transmission across skin using ultrasound. Previous research has shown transdermal delivery of insulin across skin using commercial sonicators operating at 20 kHz with intensities ranging from 12.5 to 225 mW/cm2. The goal of this research was to design and construct a small, lightweight transducer or array that could operate with a similar frequency and intensity range as a commercial sonicator used in previous transdermal ultrasound insulin experiments, but without the weight and mass of a sonicator probe. To obtain this intensity range, a cymbal transducer design was chosen because of its light, compact structure and low resonance frequency in water. To increase the spatial ultrasound field for drug delivery across skin, two arrays, each comprising of four cymbal transducers, were constructed. The first array, designated the standard array, used four cymbals transducer elements in parallel. A second array (named the stack array) used four cymbal transducers that used stacked piezoelectric discs to drive the titanium flextensional caps. Under similar driving conditions, the standard array produced intensities comparable to those achieved using a commercial sonicator.
为应用于便携式经皮给药系统，已设计出新型换能器，以利用超声波增强胰岛素透过皮肤的传输。先前的研究表明，使用工作频率为20kHz、强度范围为12.5至225mW/cm²的商用超声仪可实现胰岛素经皮递送。本研究的目标是设计并构建一个小型、轻便的换能器或阵列，其工作频率和强度范围与先前经皮超声胰岛素实验中使用的商用超声仪相似，但不具备超声仪探头的重量和质量。为获得该强度范围，选择了钹式换能器设计，因为其结构轻巧、紧凑且在水中的共振频率较低。为增加用于经皮给药的空间超声场，构建了两个阵列，每个阵列由四个钹式换能器组成。第一个阵列称为标准阵列，使用四个钹式换能器元件并联。第二个阵列（称为堆叠阵列）使用四个钹式换能器，这些换能器使用堆叠的压电盘来驱动钛质弯曲延伸帽。在相似的驱动条件下，标准阵列产生的强度与使用商用超声仪所达到的强度相当。
