Key Laboratory for Microstructural Material Physics of Hebei Province, School of Science, Yanshan University. Qinhuangdao, Hebei, 066004, PR China.
College of Liren, Yanshan University, Qinhuangdao, Hebei, 066004, PR China.
Sci Rep. 2018 May 2;8(1):6916. doi: 10.1038/s41598-018-25228-8.
A flexible and stable biomimetic SERS substrate was successfully fabricated by depositing gold (Au) nanoislands on the dragonfly wings (DW) via a simple DC magnetron sputtering system. Characterizations of the Au/DW nanostructure indicated that the optimum Au/DW-45 (sputtering time was 45 min) substrate owns high sensitivity, good stability and outstanding reproducibility. The limit of detection (LOD) for Rhodamine 6 G (R6G) was as low as 10 M and enhancement factor (EF) was calculated to be 2.8 × 10. 70-day-duration stability tests showed that Raman intensity of R6G reduced only by 12.9% after aging for 70 days. The maximum relative standard deviations (RSD) of SERS intensities from 100 positions of Au/DW-45 substrate were less than 8.3%, revealing outstanding uniformity and reproducibility. Moreover, the flexible Au/DW-45 bioscaffold arrays were employed to solve the vital problem of pesticide residues. By directly sampling from tomato peels via a "press and peel off" approach, cypermethrin has been rapidly and reliably determined with a LOD centered at 10 ng/cm and a correlation coefficient (R) of 0.987. The positive results demonstrated that the Au-based DW biomimetic arrays may offer an efficient SERS platform for the identification of various pesticide residues on real samples.
通过简单的直流磁控溅射系统在蜻蜓翅膀（DW）上沉积金（Au）纳米岛，成功制备了一种灵活稳定的仿生 SERS 基底。Au/DW 纳米结构的特性表明，最佳的 Au/DW-45（溅射时间为 45 分钟）基底具有高灵敏度、良好的稳定性和出色的重现性。Rhodamine 6G（R6G）的检测限（LOD）低至 10-10 M，增强因子（EF）计算为 2.8×107。70 天的稳定性测试表明，老化 70 天后 R6G 的拉曼强度仅降低了 12.9%。Au/DW-45 基底 100 个位置的 SERS 强度的最大相对标准偏差（RSD）小于 8.3%，显示出出色的均匀性和重现性。此外，灵活的 Au/DW-45 生物支架阵列被用于解决农药残留的重要问题。通过直接从番茄皮上进行“按压和剥落”采样，可以快速可靠地测定氯菊酯，检测限为 10ng/cm，相关系数（R）为 0.987。阳性结果表明，基于 Au 的 DW 仿生阵列可能为在实际样品中鉴定各种农药残留提供高效的 SERS 平台。
