Department of Chemistry, University of Pittsburgh, 219 Parkman Avenue, Pittsburgh, Pennsylvania 15260, United States.
Anal Chem. 2015;87(10):5013-25. doi: 10.1021/ac504679n. Epub 2015 Apr 27.
We review recent progress in the development of two-dimensional (2-D) photonic crystal (PC) materials for chemical and biological sensing applications. Self-assembly methods were developed in our laboratory to fabricate 2-D particle array monolayers on mercury and water surfaces. These hexagonal arrays strongly forward Bragg diffract light to report on their array spacings. By embedding these 2-D arrays onto responsive hydrogel surfaces, 2-D PC sensing materials can be fabricated. The 2-D PC sensors utilize responsive polymer hydrogels that are chemically functionalized to show volume phase transitions in selective response to particular chemical species. Novel hydrogels were also developed in our laboratory by cross-linking proteins while preserving their native structures to maintain their selective binding affinities. The volume phase transitions swell or shrink the hydrogels, which alter their 2-D array spacings, and shift their diffraction wavelengths. These shifts can be visually detected or spectrally measured. These 2-D PC sensing materials have been used for the detection of many analytes, such as pH, surfactants, metal ions, proteins, anionic drugs, and ammonia. We are exploring the use of organogels that use low vapor pressure ionic liquids as their mobile phases for sensing atmospheric analytes.
我们回顾了二维（2-D）光子晶体（PC）材料在化学和生物传感应用方面的最新进展。我们实验室开发了自组装方法，在汞和水表面上制造二维粒子阵列单层。这些六方阵列强烈正向布拉格衍射光，以报告它们的阵列间距。通过将这些 2-D 阵列嵌入到响应性水凝胶表面上，可以制造 2-D PC 传感材料。2-D PC 传感器利用响应性聚合物水凝胶，这些水凝胶经过化学官能化，可对特定化学物质选择性地发生体积相转变。我们实验室还开发了新型水凝胶，通过交联蛋白质同时保持其天然结构来维持其选择性结合亲和力。体积相转变会使水凝胶溶胀或收缩，从而改变其 2-D 阵列间距，并改变其衍射波长。这些位移可以通过视觉检测或光谱测量来检测。这些 2-D PC 传感材料已被用于检测许多分析物，如 pH 值、表面活性剂、金属离子、蛋白质、阴离子药物和氨。我们正在探索使用有机凝胶，其使用低蒸气压离子液体作为其流动相来感测大气分析物。
