The pharmaceutical industry has always been a key application area of high-performance liquid chromatography. High-performance liquid chromatography is widely used in drug analysis tests such as identification, impurity inspection, content determination, in vivo analysis, and the establishment of drug quality analysis methods. For example, high-performance liquid chromatography can be used to determine the content of synthetic drugs and their preparations, and eliminate the interference of impurities in the drugs, additives in the preparations and coexisting drugs.
The Pharmacopoeia of the People’s Republic of China (PPRC) or the Chinese Pharmacopoeia (ChP), compiled by the Pharmacopoeia Commission of the Ministry of Health of the People’s Republic of China, is an official compendium of drugs, covering Traditional Chinese and western medicines, which includes information on the standards of purity, description, test, dosage, precaution, storage, and the strength for each drug.It is recognized by the World Health Organization as the official pharmacopoeia of China. The Chinese Pharmacopoeia(2020 ver.) provides detailed regulations on the adjustable items and adjustable ranges of the chromatographic condition parameters in 0512 high performance liquid chromatography.
Mobile phase
The physical and chemical properties of the filler must not be changed, such as the filler material, surface modification and bonding phase must be consistent; the change from fully porous filler to surface porous filler is allowed under the premise of meeting the above conditions. Allows the use of core-shell stationary phase chromatographic columns.
Packing particle size (dp), column length (L)
After changing the particle size and column length of the chromatographic column filler, the L/ DP value (or N value) should be within the range of -25% to +50% of the original value, and the particle size and column length of the chromatographic column filler should be adjusted within a certain range.
UHPLCS USHA USHB and USHC chiral liquid chromatography column have the advantages of high resolution, high selectivity, stability and reproducibility. It is suitable for the separation of various compounds. The chromatographic packing has 1.8, 2, 3, 5, 7, 9, 10μm and other particle sizes to choose from. Chromatographic column The column length ranges from 30mm-250mm. UHPLCS USHC chiral liquid chromatography column can be applied to the separation of most chiral compounds, with excellent resolution and durability, which greatly reduces the initial cost of analysis to mass preparation.
Flow rate
If the inner diameter of the chromatographic column and the particle size of the filler are changed, the flow rate can be calculated according to the following formula:
F2=F1x[(dc2²xdp1)/(dc1²xdp2)], on this basis, according to actual use
System pressure and retention time adjustment. Among them, the isocratic elution can be adjusted within the range of ±50% at the maximum; the gradient elution shall not be adjusted in addition to the adjustment according to the above formula, and the adjustment range shall not be expanded.
Injection volume
Adjust to meet the requirements of system suitability. If the column size changes, calculate the injection volume as follows: Vinj2=V inj1x(L2xdc2²)/(L1xdc1²), and adjust according to the sensitivity requirements.
Gradient elution program (Isocratic elution is not applicable)
te2=tcax (F/F2) >[(Lxd2)/(Lxdc1)],Keep the elution volume multiples of different specifications of chromatographic columns the same, so as to ensure the same gradient change, and need to consider the difference in system volume of different instruments.It is allowed to adjust the gradient elution program according to the chromatographic column specifications, but it is necessary to ensure that the elution volume multiples of the chromatographic columns of different specifications are the same, and the gradient changes are the same.
Mobile phase ratio
The minimum proportion of mobile phase components can be adjusted within the range of relative value ± 30% or absolute value ± 2% (select the maximum value between the two)；The minimum proportion of mobile phase components must be less than (100/n) %, n is the number of components in the mobile phase. The proportion of mobile phase components can be adjusted appropriately to ensure the system suitability and meet the requirements, and the final mobile phase elution strength shall not be weaker than the original gradient elution strength. The flow ratio can be adjusted within a certain range.
Mobile phase buffer salt concentration
It can be adjusted within ±10%, and within a certain range, the buffer salt concentration is allowed to be adjusted.
In addition, the 2020 edition of the Pharmacopoeia also stipulates: Unless otherwise specified, the reference solution under each species is usually taken for 5 consecutive injections, and the peak area measurement value (or internal standard ratio or its correction factor) is The relative standard deviation should not be greater than 2.0%.And this requirement can be based on the concentration or volume of the sample solution, the chromatographic peak response and the level of precision that the analytical method can achieve, etc., the standard deviation requirements can be tightened or relaxed, and the range of relaxation or tightening can meet the requirements of the product category. The required precision requirements shall prevail. Added detailed explanations for qualitative analysis (qualification by retention time, qualitative by spectral similarity, and qualitative by mass spectrometry information provided by mass detector). Added detailed explanations for qualitative analysis (qualification by retention time, qualitative by spectral similarity, and qualitative by mass spectrometry information provided by mass detector). The measurement method of multi-dimensional liquid phase (heart-cutting two-dimensional chromatography and comprehensive two-dimensional chromatography) has been newly added.
The Chinese Pharmacopoeia(2020 ver.) will be implemented on December 30, 2020. Its promulgation and implementation will help improve the overall level of my country’s drug standards, further protect the safety of public use of drugs, promote the adjustment of the pharmaceutical industry structure, and promote my country’s pharmaceutical products to go international. Realize the leap from a major pharmaceutical country to a powerful pharmaceutical country.
Post time: Jun-11-2021
