Before carrying out drug analysis, it is necessary to be equipped with suitable testing equipment and other instruments that are the basis of drug quality testing. When using the analytical test platform for drug analysis, it is also necessary to strictly comply with the inspection operation process to guarantee the accuracy and reliability of test results. Pharmaceutical analysis and testing can study the composition, physical and chemical properties, authenticity, purity, and the content of active ingredients of drugs, which ensures that people can use drugs reasonably and effectively. And biological drug analysis mainly includes chemical method, instrumental analysis, and bioassays.
Chemical method
Chemical methods include gravimetric and titration methods. Gravimetric method refers to the separation of the substance or compound related to the component to be tested, and the content of the component is determined according to its mass. Chondroitin sulfate and fat content in pancreatic enzymes are both determined by gravimetric method. Titration refers to determining the content of the substance according to the consumption of standard solution volume. At present, the content of amino acid and sugar drugs is determined by titration method.
Chemical method is mainly used for constant analysis, with high accuracy. However, it is complicated and time-consuming, which is not conducive to automation. Currently, the research, application, and improvement of instrumental analysis methods are the hot spots of biological drug analysis.
Instrumental analysis method
Instrumental analysis method is used for micro and trace analysis with high sensitivity. It mainly includes optical method, electrochemical method, chromatography, electrophoresis, enzymatic method, and immune method.
Bioassays
This is a method for quantitative analysis of the biological activity of a drug on an organism or an isolated organ.
It can be used for impurity inspection, toxicity determination, and titer determination of drugs. The bioassay method is generally closely related to the activity and efficacy of drugs, and the results are relatively intuitive. However, the use of a large number of animals and the complication of experimental operation as well as other factors all bring about poor precision. Therefore, it is gradually replaced by the physicochemical method.
Common drug analysis methods are as follows
1. Gravimetric analysis
Gravimetric analysis is the basic chemical method in drug analysis and testing. It refers to getting a certain weight of sample, using an appropriate method to separate the measured component from other components in the sample, then converting it into a certain form to weight, and finally obtaining the content of the component. According to different separation methods, gravimetric methods are usually divided into precipitation gravimetric method, volatilization gravimetric method, extraction gravimetric method, and electrolytic gravimetric method. The accuracy of the analysis results is high.
2. Acid-base titration
Acid-base titration is to drop a reagent solution with a known accurate concentration into the solution of the tested substance until the chemical reaction is complete. According to the concentration of the reagent solution used and its volume, researchers can obtain the content of the measured component. As a chemical analysis method, acid-base titration is widely used in practical production. The content of the main components of many industrial products such as caustic soda, soda ash, ammonium sulfate, and ammonium bicarbonate is generally determined by acid-base titration. Acid-base titration is also commonly used in the analysis of raw materials, intermediate products, and finished products in the food industry.
3. PH value determination method
pH is the negative logarithm of the hydrogen ion activity in a solution and is used to indicate the acidity of a solution. The device used for pH measurement is called pH meter or acidity meter, and the acidity meter consists of two parts, a pH measurement battery and a pH indicator. The pH measurement cell is a primary cell consisting of a glass electrode, a saturated calomel electrode, and the solution to be measured. The glass electrode is the indicating electrode, and the calomel electrode is the reference electrode, which is used as a reference for indicating the potential of the electrode. The pH value determination method is now included in the pharmacopoeia of various countries.
4. Spectroscopy
The main principle of spectroscopic technology is that the drug to be detected can be radiated through different frequencies. When the frequencies in a certain range are accepted by some substances, vibration and rotation will occur. After the recording of data such as wavelength, the spectrum will be obtained. Based on the spectrum, the actual structural form of the drug and the elements of the drug can be judged and analyzed, which has the advantages of faster detection speed and higher efficiency.
5. Chemiluminescence technology
In drug analysis and detection, chemiluminescence method is a relatively common technical method, which is mainly based on the principle that the concentration of the detected substances in the chemical detection system and the chemiluminescence intensity of the system have a linear quantitative relationship under specific conditions. The instrument detects the chemiluminescence intensity of the whole system, and determines the actual content of the detected substance.
6. Chromatography
Chromatography, also known as “chromatographic analysis”, is a method and means of separation and analysis. It is mainly through the selective distribution of different substances in different phases, and the elution operation is carried out by the mobile phase of the mixture present in the stationary phase, and the different substances in the mixture will move at different speeds, which will then achieve the final effect of separation.
7. Electrophoresis
Electrophoresis is one of the important means of biotechnology and biochemical drug analysis. It has the advantages of high sensitivity, good reproducibility, wide detection range, and simple operation.
8. DNA amplification
DNA amplification technology belongs to PCR technology, which can expand the fragments of DNA samples in test tubes about a million times, and can be directly observed with the naked eye. The application of DNA amplification technology can make experiments that may take weeks or even months to be completed within a few hours. DNA amplification technology has certain sensitivity, specificity, convenience, and efficiency.
Conclusion
The quality of drugs is related to human safety and health. In order to ensure the quality of drugs, analysis and testing should be carried out in strict accordance with drug quality standards.
