Zhang L, Langmuir M E, Bai M, Rudolf Seitz W
Department of Chemistry, University of New Hampshire, Durham, NH 03824, USA.
Talanta. 1997 Sep;44(9):1691-8. doi: 10.1016/s0039-9140(97)00080-5.
We have developed a low cost pH sensor based on an optical reflective device (ORD) coupled to a toughened, lightly crosslinked aminated polystyrene membrane. Protonation of the amine group causes the polymer to swell. This is accompanied by a decrease in the turbidity of the membrane. As a result, reflected intensity measured by the ORD is a function of pH. The resulting pH sensor is inexpensive and has modest power requirements. The sensor is stable, provided the membrane is not allowed to dry out and crack. Changing ionic strength affects response both by changing the turbidity of the membrane due to refractive index effects and also by reducing the extent to which the protonated polymer swells. Increasing temperature leads to a larger change in turbidity.
我们开发了一种基于光学反射装置（ORD）与强化的、轻度交联的胺化聚苯乙烯膜耦合的低成本pH传感器。胺基的质子化会导致聚合物膨胀。这伴随着膜的浊度降低。因此，ORD测量的反射强度是pH的函数。由此产生的pH传感器价格低廉，功率需求适中。只要膜不干燥开裂，该传感器就很稳定。改变离子强度会影响响应，这是因为折射率效应改变了膜的浊度，同时也降低了质子化聚合物的膨胀程度。温度升高会导致浊度有更大的变化。
