AI 中文总结
该研究提出几何编码多接收器荧光测定策略，利用内部滤光效应的空间衰减作为定量维度，实现全范围非线性荧光定量，为强内部滤光效应下的荧光计量提供通用框架。
AI 中文摘要
内部滤光效应（IFE）会将名义上线性的荧光-浓度关系转变为与几何相关且常为非单调的响应，导致灵敏度降低、浓度模糊，以及在高光学密度下出现不准确的低估。本文提出一种空间编码多接收器荧光测定策略，该策略不消除或校正IFE，而是将IFE诱导的空间荧光衰减作为额外的定量编码维度。沿激发轴产生的荧光在独立定位的接收器窗口上进行积分，通过对联合荧光强度向量进行非线性优化来恢复浓度。选择色氨酸作为与生物医学相关的模型荧光团来验证所提出的策略。单窗口校准呈现出消失梯度边界和双值浓度反转，而两个空间分离的接收器窗口在全浓度范围内恢复了全局可识别性。对35种双接收器几何结构的筛选确定了最小不确定度构型，其平均95%误差半宽度为mean E_95=0.884 mg/L；以及最大灵敏度构型，其噪声归一化响应灵敏度达到mean S_N=3.832 a.u./(mg/L)。通过将空间衰减转换为多维浓度坐标，该方法无需稀释、单独的吸光度测量或分段校准即可扩展定量荧光分析，并为甚至在强IFE条件下的荧光计量学提供了通用计量框架。
英文摘要
The inner filter effect (IFE) transforms the nominally linear fluorescence-concentration relationship into a geometry-dependent and often nonmonotonic response, resulting in reduced sensitivity, concentration ambiguity, and inaccurate underestimation at high optical densities. Here, we introduce a spatially encoded multireceiver fluorometric strategy that does not eliminate or correct the IFE, but instead harnesses the spatial fluorescence attenuation induced by IFE as an additional quantitative encoding dimension. Fluorescence generated along the excitation axis is integrated over independently positioned receiver windows, and concentration is recovered by nonlinear optimization of the joint fluorescent intensity vector. Tryptophan was selected as a biomedically relevant model fluorophore to validate the proposed strategy. Single-window calibration exhibited vanishing-gradient boundary and two-valued concentration inversions, whereas two spatially separated receiver windows restored global identifiability across the full concentration range. Screening of 35 two-receiver geometries identified the minimum-uncertainty configuration, achieving an average 95% error half-width of mean E_95= 0.884 mg/L, and the maximum-sensitivity configuration, reaching a noise-normalized response sensitivity of mean S_N=3.832 a.u./(mg/L). By converting spatial attenuation into a multidimensional concentration coordinate, this approach extends quantitative fluorescence analysis without dilution, a separate absorbance measurement, or piecewise calibration and provides a general metrology framework for fluorescence metrology even under strong IFE conditions.
Comments13 pages, 5 figures
