Local pH Monitoring of Small Cluster of Cells using a Fiber-Optic Dual-Core Micro-Probe.
Local pH Monitoring of Small Cluster of Cells using a Fiber-Optic Dual-Core Micro-Probe.
复制标题
DOI：
10.1016/j.snb.2016.10.079
复制
发表时间：
2017-03-31
期刊：
影响因子：
--
通讯作者：
Ma Y
中科院分区：
文献类型：
--
作者：
Chen S;Yang Q;Xiao H;Shi H;Ma Y
组织和细胞的生物学研究已经使许多发现成为可能，但是这些研究仍然由于细胞异质性而具有潜在的失效风险。通过高精度技术，最近的研究表明，低数量细胞研究的结果和基于细胞群的结果之间确实存在差异。因此，迫切需要重新评估有限数量细胞的关键原则。在这项研究中，一种新的设计的双芯光纤pH微探针的制作和展示小生境环境pH传感具有高空间分辨率。采用有机改性硅酸盐（OrMoSis）溶胶-凝胶薄层，在70 μm的探针针尖上包埋pH指示剂2′，7′-双（2-羰基乙基）-5（6）-羧基荧光素（BCECF），使其功能化。在生物学相关的pH范围6.20 ~ 7.92内，I560 nm/I640 nm荧光比值与细胞间pH值呈良好的线性关系（R2 = 0.9834），pH分辨率为0.035 ± 0.005 pH单位。探头的水平空间分辨率被证明小于2 mm。此外，通过测量培养的人肺癌细胞（A549）暴露于二氧化钛纳米颗粒（TiO 2 NPs）时的局部细胞外pH变化来评估探针。结果表明，该探针具有上级的快速，局部和连续监测一小群细胞的能力，这为研究人员提供了一种快速，准确的技术来进行局部pH测量细胞异质性相关的研究。
Biological studies of tissues and cells have enabled numerous discoveries, but these studies still bear potential risks of invalidation because of cell heterogeneity. Through high-accuracy techniques, recent studies have demonstrated that discrepancies do exist between the results from low-number-cell studies and cell-population-based results. Thus the urgent need to re-evaluate key principles on limited number of cells has been provoked. In this study, a novel designed dual-core fiber-optic pH micro-probe was fabricated and demonstrated for niche environment pH sensing with high spatial resolution. An organic-modified silicate (OrMoSils) sol-gel thin layer was functionalized by entrapping a pH indicator, 2′, 7′-Bis (2-carbonylethyl)-5(6)-carboxyfluorescein (BCECF), on a ~70 μm sized probe tip. Good linear correlation between fluorescence ratio of I560 nm/I640 nm and intercellular pH values was obtained within a biological-relevant pH range from 6.20 to 7.92 (R2 = 0.9834), and with a pH resolution of 0.035 ± 0.005 pH units. The probe’s horizontal spatial resolution was demonstrated to be less than 2mm. Moreover, the probe was evaluated by measuring the localized extracellular pH changes of cultured human lung cancer cells (A549) when exposed to titanium dioxide nanoparticles (TiO2 NPs). Results showed that the probe has superior capability for fast, local, and continual monitoring of a small cluster of cells, which provides researchers a fast and accurate technique to conduct local pH measurements for cell heterogeneity-related studies.