Laser electrospray mass spectrometry (LEMS) measurement of the dissociation constant (K_d) for hen egg white lysozyme (HEWL) and N,N′,N″-triacetylchitotriose (NAG₃) revealed an apparent K_d value of 313.2 ± 25.9 μM for the ligand titration method. Similar measurements for N,N′,N″,N″’-tetraacetylchitotetraose (NAG₄) revealed an apparent K_d of 249.3 ± 13.6 μM. An electrospray ionization mass spectrometry (ESI-MS) experiment determined a K_d value of 9.8 ± 0.6 μM. In a second LEMS approach, a calibrated measurement was used to determine a K_d value of 6.8 ± 1.5 μM for NAG₃. The capture efficiency of LEMS was measured to be 3.6 ± 1.8% and is defined as the fraction of LEMS sample detected after merging with the ESI plume. When the dilution is factored into the ligand titration measurement, the adjusted K_d value was 11.3 μM for NAG₃ and 9.0 μM for NAG₄. The calibration method for measuring K_d developed in this study can be applied to solutions containing unknown analyte concentrations.

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解离常数（K的激光电喷雾质谱法（LEMS）测量_d为鸡蛋白溶菌酶（HEWL）和）Ñ，Ñ '，Ñ “-triacetylchitotriose（NAG ₃）揭示的表观ķ _d 313.2±25.9μM的值对配体滴定法。类似测量为Ñ，Ñ '，Ñ “，Ñ ”'-tetraacetylchitotetraose（NAG ₄）揭示的表观ķ _d 249.3±13.6微米。电喷雾电离质谱（ESI-MS）实验确定了K _d值为9.8±0.6μM。在第二种LEMS方法中，使用校准的测量确定NAG ₃的K _d值为6.8±1.5μM 。测得LEMS的捕获效率为3.6±1.8％，定义为与ESI羽流合并后检测到的LEMS样品的分数。当将稀释液计入配体滴定测量时，对于NAG _3而言，调整后的K _d值为11.3μM，对于NAG _4而言，调整后的K _d值为9.0μM 。本研究中开发的用于测量K _d的校准方法可以应用于含有未知分析物浓度的溶液。

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