Study on the Determination of Anesthetic and Their Applications
|School||Hunan Normal University|
|Keywords||Midazolam Bovine Serum Albumin Resonanve LightScattering Etomidate High Performance Liquid Chromatography|
In today’s clinical practice, anesthesia depends primarily on the anesthetists’experience. Since either overdosing or underdosing the patients could bring extra harm to them, the monitoring of anesthetics is of vital importance. The two major anesthetics-etomidate and midazolam-are used for clinically total intravenous anesthesia in clinical diagnosis and treatment process, and there are nowadays quite a few researches on their clinical application and side effects, but researches on the detection of etomidate and midazolam are relatively few, in consequence, it is of substantial importance to establish new methods to detect those two anesthetics efficiently.Based on our study of sample pretreatment and analysis of etomidate and midazolam, the high sensitivity and easy operation methods for the determination of etomidate and midazolam in plasmas or injections were established. Further more the interactive mechanism and energetic transfer were elaborated between midazolam with bovine serum albumin.The main contents of this thesis are as follows:1. This study begins with a brief overview of the application and effect of etomidate and midazolam in clinical anesthesia, and it goes further to analyze their detection methods. Based on the background, our research object was proposed.2. The interactive mechanism and energetic transfer between midazolam and bovine serum albumin were studied, and a new method was established to determine midazolam by fluorescence quenching. The main conclusions are:(1) The results showed that the combination constant K was5.58×104L/mol(25℃), and the number of binding sites n was1.043(25℃). The transfer efficiency of energy and distance between Midazolam and BSA was obtained (E is0.253, R0is2.64nm, r is3.17nm) based on the mechanism of Forster energy transfer. The main sort of binding force can be obtained according to the thermodynamic parameters.(2) In the Tris-HCl buffer solution (pH8.5), the fluorescent quenching value of BSA at341nm was linear with the concentration of midazolam in the range of4.0～60.0μmol/L, the detection limit was1.19μmol/L. The recoveries were within the range of96.8%～103.3%. The proposed method was proved to be sensitive and simple, as demonstrated in samples.3. A new method was established of midazolam determination by resonance light scattering. In the Tris-HCl buffer solution (pH7.3), the RLS added value was linear with concentration of midazolam in the range of0.072～4.02μmol/L. The detection limit was0.022mol/L, and the recoveries were within the range of97.2～103.3%. The method was highly sensitive and easy to operate when applied in the detection of actual samples with satisfaction.4. A novel method was established to determine etomidate by resonance light scattering. In the NaAc-HAc buffer solution (pH3.8), the RLS added value was linear with concentration of etomidate in the range of1.2～35μmol/L. The detection limit was0.37μmol/L, and the recoveries were within the range of98.0%～102.4%. The new method was simple, easy to operate, and highly sensitive with less pollution, and it was quite satisfactory when used for determining etomidate in injections.5. Because of the complexity of plasma samples, this study contributes to a new method applicable to the detection of etomidate in plasma samples based on anti-extraction and RP-HPLC technique. The samples were separated by extraction and re-extraction with HCl-chloroform and detected by UV detector. The peak area was linear with concentration of etomidate in the range of2.50～250.0μg/ml and the recoveries were within the range of99.0%～102.0%. The new method processes samples simply, raises recovery rate, enhances sensitivity, and applies easily.