The measurement of pH is important throughout many biological systems, but there are limited available technologies to enable its periodical monitoring in the complex, small volume, media often used in cell culture experiments across a range of disciplines. Herein, pad printed electrodes are developed and characterised through modification with: a commercially available fullerene multiwall carbon nanotube composite applied in Nafion, casting of hydrophobic ubiquinone as a pH probe to provide the electrochemical signal, and coated in Polyethylene glycol to reduce fouling and potentially enhance biocompatibility, which together are proven to enable the determination of pH in cell culture media containing serum. The ubiquinone oxidation peak position (E_pa) provided an indirect marker of pH across the applicable range of pH 6 – 9 (R²=0.9985, n=15) in complete DMEM. The electrochemical behaviour of these sensors was also proven to be robust; retaining their ability to measure pH in cell culture media supplemented with serum up to 20% (v/v) [encompassing the range commonly employed in cell culture], cycled >100 times in 10% serum containing media and maintain >60% functionality after 5 day incubation in a 10% serum containing medium. Overall, this proof of concept research highlights the potential applicability of this, or similar, electrochemical approaches to enable to detection or monitoring of pH in complex cell culture media.

pH值的测量在许多生物系统中都非常重要，但是有限的可用技术无法在许多学科的细胞培养实验中经常使用的复杂，小体积的培养基中进行定期监测。本文中，对焊盘印刷电极进行了开发和表征，方法是通过以下修饰进行修饰：在Nafion上应用市售富勒烯多壁碳纳米管复合材料，浇铸疏水性泛醌作为pH探针以提供电化学信号，并涂上聚乙二醇以减少结垢并潜在地增强生物相容性，共同证明可以测定含血清的细胞培养基中的pH值。泛醌氧化峰位置（E _pa）提供了在完整DMEM中pH值适用范围6 – 9（R ² = 0.9985，n = 15）内的间接pH标记。这些传感器的电化学行为也被证明是可靠的。保持其在补充了高达20％（v / v）血清的细胞培养基中测量pH值的能力[涵盖细胞培养中常用的范围]，在含10％血清的培养基中循环> 100次，并在保持> 60％的功能后在含10％血清的培养基中孵育5天。总的来说，这一概念验证研究突出了这种或类似的电化学方法在检测或监测复杂细胞培养基中的pH值方面的潜在适用性。