Abstract Concentrations of vitamin B2 in milk were evaluated based on photoluminescence (PL) peak intensities at around λ = 545 nm. PL was measured in a back-scattering configuration using a 3.2 mm diameter optical fibre bundle irradiated by ultra-violet LEDs, violet LEDs or a blue LED as the excitation light. The tip of the optical fibre bundle was dipped into commercially available whole milk, low-fat milk and non-fat milk. PL peaking at 545 nm was observed under LED irradiation. Vitamin B2 concentrations were measured using a standard addition method and a calibration curve method. Deviation between the vitamin B2 concentration measured by PL using a standard addition method and those by HPLC technique varied with wavelength of excitation light and was smallest with violet LED (405 nm) excitation. The standard deviation of results measured by PL using a calibration curve method was better than those using a standard addition method.

中文翻译：

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评估不同维生素 B2 浓度牛奶的光致发光

摘要 根据 λ = 545 nm 附近的光致发光 (PL) 峰强度评估牛奶中维生素 B2 的浓度。PL 是在反向散射配置中测量的，使用由紫外 LED、紫光 LED 或蓝光 LED 作为激发光照射的 3.2 毫米直径光纤束。将光纤束的尖端浸入市售的全脂牛奶、低脂牛奶和脱脂牛奶中。在 LED 照射下观察到 545 nm 处的 PL 峰值。使用标准添加法和校准曲线法测量维生素 B2 浓度。使用标准添加法通过 PL 测量的维生素 B2 浓度与通过 HPLC 技术测量的维生素 B2 浓度之间的偏差随激发光的波长而变化，并且在紫色 LED (405 nm) 激发下最小。