Munzke Dorit, Saunders John, Omrani Hengameh, Reich Oliver, Loock Hans-Peter
innoFSPEC, Institute for Chemistry, Physical Chemistry, University of Potsdam, Golm, Germany.
Appl Opt. 2012 Sep 10;51(26):6343-51. doi: 10.1364/ao.51.006343.
The dynamic range of fiber-optic fluorescent probes such as single fibers and fiber bundles is calculated for strongly absorbing samples, such as process liquids, foodstuffs, and lubricants. The model assumes an excitation beam profile based on a Lambertian light source and uses analytical forms of the collection efficiency, followed by an Abel transformation and numerical integration. It is found that the effect of primary absorption of the excitation light and secondary absorption of the fluorescence is profound. For fiber bundles and bifurcated fiber probes, the upper accessible concentration limit is roughly given by the absorption length of the primary and secondary absorption. Fluorescence detectors that are placed at right angles to the excitation beam axis or collinear to the beam axis are equally strongly affected by secondary absorption. A probe in which the same fiber is used for excitation and for collection of the fluorescence emerges as the fiber probe with the largest accessible concentration range.
针对诸如过程液体、食品和润滑剂等强吸收性样品，计算了单纤维和纤维束等光纤荧光探针的动态范围。该模型假定基于朗伯光源的激发光束轮廓，并使用收集效率的解析形式，随后进行阿贝尔变换和数值积分。结果发现，激发光的一次吸收和荧光的二次吸收的影响是深远的。对于纤维束和分叉光纤探针，可达到的浓度上限大致由一次吸收和二次吸收的吸收长度给出。与激发光束轴成直角放置或与光束轴共线的荧光探测器同样受到二次吸收的强烈影响。使用同一根光纤进行激发和荧光收集的探针成为可达到浓度范围最大的光纤探针。
