凝血反应压电频率动态响应规律的研究

Regularity of Dynamic Piezoelectric Frequency Response in Blood Coagulation

目的探讨体外凝血反应引起压电传感器频率变化的规律,建立压电凝血终点判断模型。方法理论分析凝血反应导致反应体系黏度密度变化规律,推导适合的频率动态响应模型并建立新的压电凝血终点判断法;用建立的反应模型检测凝血酶原时间(PT),并删减和延长不同长度的原曲线末段,然后以新方法和既有的最大拟合曲率判断法(MCF)判断终点并比较。结果根据反应体系黏度密度变化规律,理论推导出体外凝血反应过程中压电频率动态响应规律符合F=(f0-?f)+1+?e(t-ft0)/dt模型;根据该模型建立了新的反S拟合曲线法(ISF);与既有的最大拟合曲率法相比,前者检测速度更快(P<0.01),重复性更好(P<0.01)。结论该反S模型可以较理想地反映凝血反应中压电频率动态变化规律,ISF法可以理想的判断压电凝血终点。

OBJECTIVE To study the principle of dynamic response frequency in piezoelectric coagulation and establish a new method for endpoint determination of the analysis. METHODS A new dynamic piezoelectric frequency response model and endpoint determination method for the piezoelectric coagulation were derived, based on the theoretic analysis of viscosity and density changes in coagulation reaction system. The different final segments of the raw data among different coagulation curves were cut or extended respectively when a prothrombin test was performed by different reaction models. Then judged and compared the endpoint of coagulation reaction between new endpoint determination method and the old method-maximal curvature of fitting curve （MCF）. RESULTS The trend of dynamic frequency response of piezoelectric coagulation corresponded with the inverse S curve F =（f0-△f）＋△f/1＋e^（t-t0）/dtderived from theory according to the change regularity of the viscosity and density in the reaction system. Compared with the MCF, the inverse S-fitting determination method （ISF） based on the new model could improve the reproducibility （P~ 0. 01） and save more detection time （/9~ 0. 01）. CONCLUSIONS The new derived inverse S model can represent the principle of the dynamic frequency response perfectly, and the ISF based on it can be used for the endpoint determination in piezoelectric coagulation.