Sun Q, Tran M, Smith B W, Winefordner J D
Department of Chemistry, University of Florida, P.O. Box 117200, Gainesville, FL 32611-7200, USA.
Talanta. 2000 Jun 21;52(2):293-300. doi: 10.1016/s0039-9140(00)00340-4.
The feasibility of using laser induced-breakdown spectroscopy (LIBS) as a quick and simple method to analyze trace elemental concentrations in the stratum corneum of human skin was investigated. A 60 mJ pulse(-1) Nd:YAG laser operating at 1064 nm was used to form the laser induced plasma. Zinc was chosen for this study. By using poly-(methyl methacrylate) (PMMA) solution to coat the slides, zinc standard solutions were dispersed on the slides with the help of a centrifuge. The percent of R.S.D. of the dispersed area size obtained from 17 measurements was 6%. The precision from intra-measurements (precision on one slide) and inter-measurements (precision between slides) was 4-8% and less than 1%, respectively. A calibration curve with a linear correlation coefficient of 0.998 and a detection limit of 0.3 ng cm(-2) were obtained. An aqueous zinc solution or zinc ointment was deposited on the biceps area of the forearms of several volunteers for a time period of 30 min and 2.75 h. Six skin layers of 2-3 mum each in thickness were then removed using cyanoacrylate glue without causing any pain for the volunteers. The results indicated that Zn was absorbed through the skin and the concentration decreased exponentially with depth into the skin. The results indicate that LIBS is a useful tool for trace elemental analysis in human skin.
研究了使用激光诱导击穿光谱法（LIBS）作为一种快速简便的方法来分析人体皮肤角质层中痕量元素浓度的可行性。使用一台输出波长为1064nm、脉冲能量为60mJ的Nd:YAG激光器来形成激光诱导等离子体。本研究选择了锌元素。通过使用聚甲基丙烯酸甲酯（PMMA）溶液涂覆载玻片，借助离心机将锌标准溶液分散在载玻片上。从17次测量获得的分散区域尺寸的相对标准偏差（R.S.D.）百分比为6%。测量内精度（在一张载玻片上的精度）和测量间精度（不同载玻片之间的精度）分别为4 - 8%和小于1%。获得了线性相关系数为0.998且检测限为0.3 ng cm⁻²的校准曲线。将锌水溶液或锌软膏涂抹在几名志愿者前臂的二头肌区域，持续30分钟和2.75小时。然后使用氰基丙烯酸酯胶水无痛地去除每层厚度为2 - 3μm的六层皮肤。结果表明，锌通过皮肤被吸收，且其浓度随深入皮肤的深度呈指数下降。结果表明，LIBS是用于人体皮肤痕量元素分析的一种有用工具。
