此外，若样本数值已经超出最高或最低标准品的范围，流式细胞术文献中通常会采用外推法进行处理，而QuickCal模板会自动执行这一操作。

此外多说一句，Spherotech的Calibration kit （如8峰球），原理上也是可以用来做流式定量的。但是有一个问题，Spherotech的具体荧光物质是保密的，用FITC通道校准的荧光，可能不是FITC, 而是一个与FITC相近的荧光。比如PE通道，它的8峰球也是可以做线性的，但是spherotech的球是Hard dyed(即内染的），所以根本不可能是PE蛋白（蛋白不能内染） ,如果我们此时用PE标记的抗体去定量，中间会产生误差。

References:

1 Kondratov, K., Nikitin, Y., Fedorov, A., Kostareva, A., Mikhailovskii, V., Isakov, D., Ivanov, A., & Golovkin, A. (2020). Heterogeneity of the nucleic acid repertoire of plasma extracellular vesicles demonstrated using high‐sensitivity fluorescence‐activated sorting. Journal of Extracellular Vesicles, 9(1), 1743139. https://doi.org/10.1080/20013078.2020.1743139

2 Mizutani, K. (2007). The Importance of Anti-HLA-Specific Antibody Strength in Monitoring Kidney Transplant Patients. American Journal of Transplantation, 7, 1027-1031. 

3 Pevna, M. (2014). Residual Cancer Lymphocytes in Patients With Chronic Lymphocytic Leukemia After Therapy Show Increased Expression of Surface Antigen CD52 Detected Using Quantitative Fluorescence Cytometry. Clinical Lymphoma, Myeloma & Leukemia, 14(5), 411-418. 

4 Thedsawad, A. (2011). Development of flow cytometry for detection and quantitation of red cell bound immunoglobulin G in autoimmune hemolytic anemia with negative direct Coombs test. Asian Pac J Allergy Immunol, 29, 364-367.