Spatially monitoring oxygen level in 3D microfabricated cell culture systems using optical oxygen sensing beads.
Spatially monitoring oxygen level in 3D microfabricated cell culture systems using optical oxygen sensing beads.
复制标题
使用光学氧传感珠空间监测 3D 微加工细胞培养系统中的氧气水平。
DOI：
10.1039/c3lc41366g
复制
发表时间：
2013
期刊：
影响因子：
6.1
通讯作者：
Carrier,RebeccaL
中科院分区：
文献类型：
--
作者：
Wang,Lin;Acosta,MiguelA;Leach,JennieB;Carrier,RebeccaL
在细胞培养中，测量和监测单细胞水平(几十微米级)的局部氧浓度的能力通常是可取的，但很难实现。在这项研究中，制备了生物相容的氧敏微珠，并测试了其在三维微图案化细胞培养系统中实时监测和绘制局部氧浓度的潜力。每个氧敏小球都由一个二氧化硅核和一个聚二甲基硅氧烷(PDMS)壳组成，前者负载氧敏感的Ru(Ph2hen3)Cl2染料和氧不敏感的尼罗蓝参考染料，后者具有生物兼容性。将人肠上皮Caco-2细胞接种于微孔阵列构图的PDMS和I型胶原基质上，培养3~7天，然后与氧敏小球接触。利用图像分析算法将微珠的荧光强度转换为培养系统中的分氧压，数十微米尺寸的氧敏微珠能够对微制造系统中的局部氧气浓度进行空间测量。结果一般表明，井内的氧气水平低于井顶，局部氧气水平取决于细胞培养表面的结构特征。有趣的是，细胞培养底物的化学成分似乎也影响氧气水平，与基于PDMS的细胞培养系统相比，I型胶原细胞培养系统的氧气浓度较低。总的来说，研究结果表明，氧敏小球可以实现对三维微细加工细胞培养系统中微环境氧水平的实时和局部监测。
Capability of measuring and monitoring local oxygen concentration at the single cell level (tens of microns scale) is often desirable but difficult to achieve in cell culture. In this study, biocompatible oxygen sensing beads were prepared and tested for their potential for real-time monitoring and mapping of local oxygen concentration in 3D micro-patterned cell culture systems. Each oxygen sensing bead is composed of a silica core loaded with both an oxygen sensitive Ru(Ph2phen3)Cl2 dye and oxygen insensitive Nile blue reference dye, and a poly-dimethylsiloxane (PDMS) shell rendering biocompatibility. Human intestinal epithelial Caco-2 cells were cultivated on a series of PDMS and type I collagen based substrates patterned with micro-well arrays for 3 or 7 days, and then brought into contact with oxygen sensing beads. Using an image analysis algorithm to convert florescence intensity of beads to partial oxygen pressure in the culture system, tens of microns-size oxygen sensing beads enabled the spatial measurement of local oxygen concentration in the microfabricated system. Results generally indicated lower oxygen level inside wells than on top of wells, and local oxygen level dependence on structural features of cell culture surfaces. Interestingly, chemical composition of cell culture substrates also appeared to affect oxygen level, with type-I collagen based cell culture systems having lower oxygen concentration compared to PDMS based cell culture systems. In general, results suggest that oxygen sensing beads can be utilized to achieve real-time and local monitoring of micro-environment oxygen level in 3D microfabricated cell culture systems.