SO₂ and its derivatives (HSO₃⁻, SO₃²⁻) play a significant important role in many industries and organisms. Based on coumarin and benzopyranose, a promising NIR ratiometric fluorescent probe BAOA (11-oxo-2,2′,3,3′,6,7,7′,8′-octahydro -1H,1′H,5H,6′H,11H- [10,12′-bipyrano [2,3-f] pyrido [3,2,1-ij] quinolin]-13′-ium perchlorate) was designed and developed to detect HSO₃⁻ rapidly and sensitively. The sensing mechanism was Michael addition reaction, in which, strongly nucleophilic HSO₃⁻ attacked carbon-carbon double bonds and BAOA-HSO₃ was formed. A superior linear calibration curve between the fluorescence ratio I₄₉₀/I₇₂₂ and concentrations of HSO₃⁻ was obtained in the range of 1.25–8.75 μmol/L and the LOD was figured out as 63.0 nmol/L. Cell experiments showed that BAOA could not only locate mitochondria, lysosomes, ER and Golgi but also detect exogenous HSO₃⁻ in living cells.

SO ₂及其衍生物（HSO ₃ ^-、SO ₃ ^2-）在许多工业和生物体中发挥着重要的作用。基于香豆素和苯并吡喃糖，一种有前途的 NIR 比率荧光探针 BAOA (11-oxo-2,2',3,3',6,7,7',8'-octahydro -1H,1'H,5H,6' H,11H- [10,12'-bipyrano [2,3-f] pyrido [3,2,1-ij] quinolin]-13'-ium perchlorate) 被设计和开发用于快速、灵敏地检测 HSO ₃ ^-。传感机制是迈克尔加成反应，其中强亲核的HSO ₃ ^-攻击碳-碳双键并形成BAOA-HSO ₃。荧光比 I ₄₉₀之间的优异线性校准曲线/I ₇₂₂和 HSO ₃ ^{- 的}浓度范围为 1.25–8.75 μmol/L，LOD 计算为 63.0 nmol/L。细胞实验表明，BAOA不仅可以定位线粒体、溶酶体、内质网和高尔基体，还可以检测活细胞中的外源性HSO ₃ ^-。