1.Impurity profiling of macrolide antibiotics by liquid chromatography-mass spectrometry.
Acta Pharmaceutica Sinica 2013;48(5):642-7
Macrolide antibiotics are broad-spectrum, with activity against a range of Gram-positive, Gram-negative organisms and some anaerobes. The components of macrolide antibiotics are generally complicated. Therefore, it is very important to establish impurity profiles of these antibiotics to ensure their safety and process control. Compared with classical methods, the liquid chromatography-mass spectrometry method is particularly advantageous to characterize minor components at trace levels in terms of sensitivity, efficiency and selectivity, thus more and more widely used in establishments of impurity profiles. In this study, the general approaches to characterize minor components in complex pharmaceutical matrix, fragmentation pathways of 14- and 16-membered macrolide antibiotics and the establishment of the impurity profile of acetylspiramycin were given to provide valuable enlightenments to establish the impurity profiles of pharmaceutical products.
2.Theory of selectivity of RP-LC C18 column and its application
Acta Pharmaceutica Sinica 2010;45(5):555-9
In recent years, more and more researchers focus on the selectivity of RP-HPLC columns. Among these columns, C18 column is the most commonly used the column. Yet even the same filler can not give us the same separation effect with the columns of different brands and different types, therefore, it is important to choose the suitable HPLC column for carrying out an experiment. After study in recent years, some column classification, selection methods (e.g.: column parameter method, F value method) have been achieved and contributed to the finding of suitable columns and reducing the blindness of column selection. This paper summarizes the advantages of these methods and their limitations in the application process, and gives some advices and expectations to pharmaceutical analysis works based on the works of other researchers.
3.Strain-dependent effects of fluoxetine on tail suspension test in mice
Ming HU ; Guohua CHEN ; Changqin LIU
Chinese Journal of Behavioral Medicine and Brain Science 2013;(4):306-307
Objective To study the strain difference in response to the antidepressant fluoxetine in mouse tail suspension test.Methods Two outbred mouse strains (KM and ICR) and three inbred mouse strains (C57BL/6,Balb/c and DBA/2) were used in this study.They were treated with the selective serotonin reuptake inhibitor (SSRI) fluoxetine or saline and the immobility time in tail suspension test was recorded.Results There was significant difference of baseline immobility time among different stains with C57BL/6 the most immobile((145.0 ±16.8) s) and DBA/2 the least ((34.5 ± 6.1)s).Fluoxetine significantly decreased the immobility time in C57BL/6 ((116.0 ± 10.3) s vs (145.0 ± 16.8) s) of control),Balb/c ((44.3 ± 6.2) s vs (75.3 ± 10.3) s) of control) and DBA/2 mice ((16.6 ± 4.3) s vs (34.5 ± 6.1) s) of control),while the immobile time of KM and ICR mice was not influenced by fluoxetine.Conclusion The effects of fluoxetine in tail suspension test are strain dependent.Fluoxetiue exhibits antidepressant effects in C57BL/6,Balb/c and DBA/2 mice,but not in KM and ICR mice.
4.Near Infrared Correlation Coefficient Method with Characteristic Spectral Band for the Determination of Illegal Addition of Sildenafil Citrate in Capsules of Chinese Traditional Medicine
Xueliang WANG ; Yanchun FENG ; Changqin HU
Chinese Journal of Analytical Chemistry 2009;37(12):1825-1828
A near infrared (NIR) method for the detection of illegal addition of sildenafil citrate in capsules of Chinese traditional medicine was constructed. The diffuse reflectance near infrared spectra were recorded using integrated sphere and fiber optics respectively. Using the spectra of the sildenafil citrate standard as Reference spectra, the threshold of the correlation coefficient was set up based on the minimum effective concentration of the sildenafil citrate. By comparing the threshold with the correlation coefficient between the tested spectra and the Reference spectra in the selected spectral range, the tested sample contains sildenafil citrate is determined. For the integrated sphere method, the spectral range of 6070-5800 cm~(-1) and 4170-4070 cm~(-1) were selected, and 70% was set as threshold. For the fiber method, 6070-5800 cm~(-1) and 65% were used. 79 and 247 batches of the Chinese traditional medicines contained sildenafil citrate collected from the Chinese market were used to validate the two methods separately. The accuracy of the integrated sphere method was 91.14%, and that of f iber method was 87.45%.
5.Evaluation of Piecewise Direct Standardization Algorithm for Near Infrared Quantitative Model Updating
Chenchen XI ; Yanchun FENG ; Changqin HU
Chinese Journal of Analytical Chemistry 2014;(9):1307-1313
The near infrared ( NIR ) spectra of 76 batches of the amoxicillin capsules from different manufacturers and their corresponding content powder without capsules cell were used to find some quantitative indicators to evaluate whether the piecewise direct standardization ( PDS ) algorithm succeeded in NIR quantitative model updating. 54 batches were used to construct the NIR quantitative model for capsule preparation. All the NIR spectra of amoxicillin capsules were divided into five classes by cluster analysis, and each class can be regarded as a homology sample set. The average spectrum for each homology sample set was calculated. Ten to Fifteen spectra were selected from each homology sample set as the corresponding master spectra of the PDS algorithm to correct all the NIR spectra of the amoxicillin content powder respectively. Then the corrected spectra were predicted by the constructed NIR quantitative model for amoxicillin capsules. The prediction error for each corrected powder spectrum, and the correlation coefficient between each corrected powder spectrum and the average spectrum of the corresponding homolog sample set which the PDS master spectra came from, were calculated. Finally, the relationship between the prediction error and its corresponding correlation coefficient were studied. It was found that the correction results correlated closely with the selected master spectra set in PDS algorithm. The bigger the correlation coefficient ( r) , the better the correction results. In general, when r is less than 99%, it can be judged that the PDS correction is failed. At this condition, the prediction error is often more than 5%. Therefore, the correlation coefficient between the corrected spectrum and its corresponding average spectrum of the homology sample set can be used as an indicator to evaluate the efficiency of the PDS correction.
6.In-vitro Antibacterial Effect and Sterility Test of Danshen Injection
Xinmei ZHANG ; Guirong ZHANG ; Changqin HU
Traditional Chinese Drug Research & Clinical Pharmacology 2000;0(05):-
Objective To investigate the in-vitro antibacterial effect and sterility test of Danshen injection(DI). Methods Three kinds of in-vitro antibacterial and bacteriostatic methods were used to investigate the in-vitro antibacterial effect of DI and to establish its sterility test according to the results of the antibacterial effects. By validation test, the validity of its sterility test was evaluated. Results The results of doubling dilution test showed that the minimum bacteriostatic concentration of DI is 0.098 mg/mL, and its minimum bactericidal concentration is 1. 563 mg/mL in ethanolsulfate medium and 0.195 mg/mL in nutrient meat soup medium. Rate of recovered bacterium was much more than 80% by membrane filtration method. Conclusion DI has strong in-vitro bacteriostatie effects for staphylococcus aureus and the effectual method of its sterility test is membrane filtration method.
7.The compatibility between packing material and ipratropium bromide aerosol.
Zhihua YUE ; Diandian SHEN ; Changqin HU
Acta Pharmaceutica Sinica 2010;45(8):1035-8
With the establishment of HPLC and LC-MS methods to determine the related substances and the content of active pharmaceutical ingredient (API) in ipratropium bromide aerosol products, several packing material-related impurities were identified, including antioxygen BHT and antioxygen 2246. Results showed that these leachable additives from the packing materials may present at a relative high level in the drug solution, and the low content of API in the drug products is usually due to the adsorption of the packing material as well as the leaking of contents. The current available assay methods for the control of ipratropium bromide aerosol products are often lack of specificity and unable to assure the drug quality effectively. To meet the increasing attention on the regulations of drug packing materials, our research would be a pilot study, indicating that the inappropriate packing materials could cause the migration and adsorption of the active ingredients, and the importance to have compatibility studies between packing materials and drugs.
8.Interpretation of the Test Method for Bacteriostat Effect in Chinese Pharmacopoeia (2015 Edition)
Xiaoli YANG ; Congying HE ; Jinfang SHENG ; Changqin HU
China Pharmacist 2016;19(9):1740-1742
Objective:To interpret the main revision about the test method for bacteriostat effect in Chinese Pharmacopoeia(2015 edition). Methods:The main difference of the bacteriostat effect test method in Chinese Pharmacopoeia(2015 edition) and (2010 edi-tion) was compared. Results:The bacteriostat effect test method in the 2015 edition was revised at a comparatively large scale in the positioning of bacteriostat effect test, product classification, assessment criteria and so on. Conclusion: The bacteriostat effect test method in Chinese Pharmacopoeia (2015 edition) gradually improves the check standards in line with the international standards.
9.Construction of the quantitative structure retention relationship of cefdinir related substances.
Chen WANG ; Jin LI ; Yanchun FENG ; Ying LIU ; Changqin HU
Acta Pharmaceutica Sinica 2015;50(9):1161-6
The molecular descriptors of impurities with known structure in cefdinir were calculated, selected and associated with the chromatographic retention behavior to establish a model. This quantitative structure retention relationships (QSRR) model for the related substances of cefdinir was established under specific chromatographic condition and verified by other impurities. 12 molecular descriptors were used to establish the QSRR model, F_AFRBWF, Blbn_J, SsCH3, SssCH2, SsNH2, SssNH, SssS, SHdCH2, EEM_AFc, EEM_AFpl, EEM_XFpl and Pi_MaxQ. The relativity between true values and predictions in QSRR of cefdinir is R2 = 0.9836 (n = 18), ΔRRT is no more than 0.154, as 10.17% in RRT. The results indicate that the QSRR model for the related substances of cefdinir can be used to evaluate the analysis methods for related substances and predict the chromatographic behavior of new impurities, which will provide a new way for the evaluation of the effectiveness for drug quality control.
10.Interpretation and Countermeasure of the Microbiological Examination for Nonsterile Products:Tests for Specified Microorganisms in Chinese Pharmacopoeia (2015 Edition)
Xiaoli YANG ; Hui LI ; Yingying MA ; Jinfang SHENG ; Changqin HU
China Pharmacist 2016;19(4):748-752
Objective:To interpret the main revision of the microbiological examination for nonsterile products:tests for specified microorganisms in Chinese Pharmacopoeia (2015 edition). Methods:The microbiological examination for nonsterile products:tests for specified microorganisms in Chinese Pharmacopoeia (2015 edition) was compared with the relevant content in the 2010 edition, and then the differences were investigated. Results:Microbiological examination for nonsterile products:tests for specified microorganisms in Chinese Pharmacopoeia (2015 edition) had been revised at a comparatively large scale in the inspection items, test method, micro-bial culture system, the quality control concept and so on. Conclusion:Microbial inspection system in Chinese Pharmacopoeia (2015 edition) is gradually improved to become a high standard check system in line with the international standards.