Homma R, Takada Y, Karube I, Kimura K, Muramatsu H
Department of Blood Products, National Institute of Health, Tokyo, Japan.
Anal Biochem. 1992 Aug 1;204(2):398-404. doi: 10.1016/0003-2697(92)90257-8.
A novel apparatus called a quartz chemical analyzer (QCA) has been developed using a quartz crystal resonator. This apparatus measures sample viscosity changes based on resonant frequency changes of the quartz crystal. The apparatus was used to determine bacterial endotoxin concentrations by monitoring the gelation reaction of Limulus amebocyte lysate. The QCA determined endotoxin concentrations with good accuracy and reproducibility in the range of 0.001-3 EU/ml for endotoxin standard (JP XII). For endotoxin determination in human whole blood and plasma samples, the inhibitory reaction was eliminated by pretreatment of a fourfold dilution at 60 degrees C and incubation for 30 min. There are many advantages of the QCA method compared with the turbidimetric and chromogenic methods. For example, QCA can measure sample viscosity changes with high sensitivity and accuracy because QCA detects minor resonant frequency changes and the frequency data give a numerical value for easy quantitation. QCA can examine turbid samples, and the required quantities of samples and reagents are small, since the quartz crystal detects sample viscosity changes directly. The endotoxin determination time may be shortened by raising the reaction temperature, and QCA can detect other types of coagulation reactions.
一种名为石英化学分析仪（QCA）的新型仪器已利用石英晶体谐振器开发出来。该仪器基于石英晶体的共振频率变化来测量样品粘度的变化。该仪器通过监测鲎试剂的凝胶化反应来测定细菌内毒素浓度。对于内毒素标准品（日本药典第十二版），QCA在0.001 - 3 EU/ml范围内测定内毒素浓度时具有良好的准确性和重现性。对于人全血和血浆样品中的内毒素测定，通过在60℃下进行四倍稀释并孵育30分钟的预处理消除了抑制反应。与比浊法和显色法相比，QCA法有许多优点。例如，QCA可以高灵敏度和准确性地测量样品粘度变化，因为QCA检测微小的共振频率变化，并且频率数据给出数值便于定量。QCA可以检测浑浊样品，并且所需的样品和试剂数量少，因为石英晶体直接检测样品粘度变化。提高反应温度可以缩短内毒素测定时间，并且QCA可以检测其他类型的凝固反应。
