摘要本文通过实验研究了一种激光换能片的力学效能,该换能片能够将脉冲激光能量转换成冲击波,冲击波经药液耦合传递至皮肤,可以暂时性克服皮肤角质层屏障,形成“微型通道”,短时间内使药液透过角质层进入皮肤,实现透皮给药。67447
对于不同的激光换能片,要想使得激光冲击波力学效应达到较好,需要对不同的参数组合进行实验,包括激光能量、激光光斑面积、药液盒孔径、药液盒厚度等参数,每一个参数变化都会影响换能片的力学效应。
本文实验中采用的激光汇聚透镜焦距为150mm,依次固定离焦度而改变激光能量进行激光冲击力检测。由检测数据的分析结果表明,当离焦度较小(0mm~-20mm)时,冲击力的幅值会随着激光能量的增加而趋于饱和。具体表现为,当光斑面积固定,随激光脉冲能量的增加,冲击力的幅值逐步增加至峰值,以后便不再显著增加;当离焦度较大(-80mm~-90mm)时,冲击力的幅值随激光能量的增加呈现起伏不定的振荡变化。
上述换能片产生的冲击力的幅值在较小离焦度下随激光能量密度增加所呈现的饱和变化关系,有实际的应用价值:当激光冲击力的幅值达到透皮给药的阈值要求,且接近饱和强度时,若再增加激光能量,冲击力的幅值并不随之显著增加,这降低了对于激光能量控制精度的要求,有利于保护皮肤不受损伤;而在较大离焦度的情况下,冲击力幅值随激光能量增加所呈现的振荡变化表现,会导致冲击力的大小难以掌控,不适于在实际透皮给药操作时采用。
本文研究中使用的激光换能片,其结构设计为一套包括了约束层、吸收层、保护层和药液盒的一体化“插片”,总厚度约1.3 mm,直径约12 mm,换能片的设计结构紧凑、易于符合临床上的一次性使用要求,方便装卸,便于批量生产,适合于无损伤皮下微量给药用途。
本文的研究结果,可以为此换能片的结构设计与改进提供实验依据。
毕业论文关键词 激光冲击波(激光压力波、光机械波)等离子体 激光换能片 力学效应
毕业设计说明书(论文)外文摘要
Title Study of Mechanical effects of laser shock wave and its influencing factors
Abstract
This paper passing through experiments study on mechanical efficiency of a kind of laser transducing sheet. The transducing sheet can convert laser energy into shock wave. This experiment is as a basis for the laser transdermal administration. Shock wave through the liquid coupling transfer to the skin. There will be a micro-channel. It can temporarily overcome the skin stratum corneum barrier. It can make the liquid through the stratum corneum into the skin within a short time and realize the transdermal drug delivery, this is the principle of the laser transdermal delivery.
For the different laser transducer film, to make laser blast to achieve better mechanical effects, Need to experiment with different combinations of parameters Including laser energy, the laser spot size, the liquid cartridge aperture, the liquid cell thickness and other parameters, Each parameter can influence mechanical effects of the transducer film.
The laser convergent lens with focal length of 150mm used in this experiment, we fixed defocus degree sequentially and change laser energy to do the test of laser impact force. The results of test data show us, When the defocus degree is small(0~-20mm), Amplitude of the impact force increase as the laser energy density and saturation. Specific performance, when we fixed the spot size, As the increasing of laser pulse energy, amplitude of the impact force gradually increase to a peak and then will not longer increased significantly. When defocused degree is large(-80mm~-90mm),there will be a oscillation of the Impact force amplitude increasing when we add the laser energy( No saturation trends).