Jacobson James W, Oliver Kerry G, Weiss Christy, Kettman John
Luminex Corporation, Austin, Texas, USA.
Cytometry A. 2006 May;69(5):384-90. doi: 10.1002/cyto.a.20293.
Typically, bead-based assays ("bead arrays") use the mean or median value of a population of measurements to judge ligand binding or other activity, which results in a change in fluorescence intensity. Individual bead measurements are used here to calculate population parameters integral to the measurement of a bead array.
Using a commercially-available instrument designed for bead array measurements, a set of beads were labeled with biotin and then titrated with PE-Streptavidin. Data were collected under normal machine conditions as well as variations.
The "sensitivity" of the measurements was determined using parametric and nonparametric statistical methods as well as regression analysis over a limited range of the titration (concentration vs. response profile).
Results at low ligand concentrations suggest that precise measurements with bead array systems require a large number of individual bead measurements to be acquired. Individual bead measurements should be used to determine the mean and confidence intervals for the calculated measurements. These results also apply to regression analysis of concentration-response profiles. Furthermore, features of the instrument can be manipulated to achieve increased sensitivity and detection of lower amounts of ligand bound to the bead populations.
通常，基于微珠的检测方法（“微珠阵列”）使用一组测量值的均值或中值来判断配体结合或其他活性，这会导致荧光强度发生变化。此处使用单个微珠测量值来计算微珠阵列测量中不可或缺的总体参数。
使用一台为微珠阵列测量设计的商用仪器，将一组微珠用生物素标记，然后用PE-链霉亲和素进行滴定。在正常仪器条件以及各种变化条件下收集数据。
使用参数统计方法、非参数统计方法以及在滴定的有限范围内进行回归分析（浓度与响应曲线）来确定测量的“灵敏度”。
低配体浓度下的结果表明，使用微珠阵列系统进行精确测量需要获取大量单个微珠测量值。应使用单个微珠测量值来确定计算测量值的均值和置信区间。这些结果也适用于浓度-响应曲线的回归分析。此外，可以操控仪器的特性以提高灵敏度并检测与微珠群体结合的更低量配体。
