Molecularly Imprinted Polymer And Flow Injection Chemiluminescence Based Determination Of Theophylline Substances

Theophylline drugs are attributed to methylxanthine drugs in pharmaceutical chemistry,which can relax bronchial smooth muscle.These drugs usually used for anti-asthma,anti-inflammation and cough treatment.Theophylline drugs are widely used in China because of their efficiency,convenience and low cost.However,the range of effective blood concentration is narrow and treatment dose is closed to the toxic dose of these drugs.Once the blood concentration of the theophylline drugs out of control,side effects occur in clinical practice,and even causes toxic reaction.Therefore,real-time blood drug concentration monitoring is extremely important for patients who use theophylline drugs,especially for patients with severe or continuous medication.At present,the main monitoring methods for theophylline drugs include HPLC,Gas chromatography,UV-visible spectrophotometer and Capillary electrophoresis.However,this kind of detection method has high technical requirements,large consumption,and high maintenance cost of the instrument,making it difficult to be widely used.Therefore,it is of great significance to develop new,easily popularized and low-cost detection technologies for the treatment of patients and the saving of medical resources.Based on this,this study combined molecular imprinting technology with flow injection chemiluminescence method to make sensors to detect theophylline substances.Molecularly imprinted polymers can be synthesized with cavities matching the shape,size and functional groups of the target molecule.Molecularly imprinted polymers can achieve specific recognition of the target molecule,which can be likened to antibody recognition of antigens or highly selective substrate of enzymes.Chemiluminescence is a kind of spectral analysis method without external light source.The sensor combines the advantages of the two technologies,and uses the flow injection technology to inject samples at the same time,which can collect signals in the thermodynamic non-equilibrium state,with simple operation and high stability.The combination of the two techniques can achieve the determination of target molecules in complex samples,which can effectively reduce the cost and has potential clinical value.The research content of this research includes the following four parts:1.Luminol-H₂O₂-NaOH-theophylline chemiluminescence system is established to determine theophylline.The sample is loaded by using flow injection technology,the chemiluminescence conditions and parameters are optimized.As the results,acquired linear equation is?I=7×10⁸c+230,the linear correlation coefficient R²=0.9963,linear range is 1×10^-72×10^-6mol/L.The theophylline solution is analyzed for 11 parallel determination at the same condition,and the relative standard deviation（RSD）of this method is 2.56%,this system can be used to analysis the samples.2.The route of flow injection was adjusted,the parameters of the system were optimized,and the system was combined with KMnO₄-HCHO chemiluminescence system for the determination of aminophylline.Within the concentration range of5×10^-41×10^-3mol/L,there is a linear relationship between relative chemiluminescence intensity and aminophylline,and the concentration limit is 2×10^-55 mol/L.The established method can be used for the determination of aminophylline.3.In order to further improve the selectivity of this method,the molecularly imprinted polymer of dihydroxypropylline was synthesized by means of bulk polymerization.The synthetic polymer was used as the recognition element and combined with Luminol-H₂O₂ chemiluminescence system to make a sensor for the determination of dihydroxypropylline.The linear range of the method is 1×10^-61×10^-4mol/L,and the concentration limit is 1×10^-77 mol/L.4.Doxofylline is determined by molecular imprinted and flow injection chemiluminescence sensor.The adsorption performance of the sensor is studied and the selectivity of the method can be improved effectively.The regression equation is?I=45.419c+345.06,the linear range is 1×10^-65×10^-5mol/L,and the concentration limit is 1×10^-77 mol/L.The sensor can be used to determine the doxofylline in complex samples.