Objective: To systematically analyze the revisions content and technological development trends of microbiological standards in the Chinese Pharmacopoeia (ChP) 2025 Edition, and explore its novel requirements in risk-based pharmaceutical product lifecycle management.
Methods: A comprehensive review was conducted on 26 microbiological-related standards to summarize the revision directions and scientific implications from perspectives including the revision overview, international harmonization of microbiological standards, risk-based quality management system, and novel tools and methods with Chinese characteristics.
Results: The ChP 2025 edition demonstrates three prominent features in microbiological-related standards: enhanced international harmonization, introduced emerging molecular biological technologies, and established a risk-based microbiological quality control system.
Conclusion: The new edition of the Pharmacopoeia has systematically constructed a microbiological standard system, which significantly improves the scientificity, standardization and applicability of the standards, providing a crucial support for advancing the microbiological quality control in pharmaceutical industries of China.

Penicillins are one type of the most important antibiotics used in the clinic.Control of drug impurity profiles is an important part of ensuring drug safety.This is particularly important in penicillins where polymerization can lead to polymers as elicitors of passive cutaneous anaphylaxis.The current under-standing of penicillin polymerization is based on reactions with amino groups,but no comprehensive mechanistic understanding has been reported.Here,we used theoretical calculations and column switching-LC/MS techniques to study penicillin dimerization.Ampicillin and benzylpenicillin were selected as representative penicillins with or without amino groups in the side chain,respectively.We identified four pathways by which this may occur and the energy barrier graphs of each reaction process were given.For benzylpenicillin without an amino group in the 6-side chain,dimerization mode A is the dominant mode,where the 2-carboxyl group of one molecule reacts with the β-lactam of another molecule.However,ampicillin with an amino group in the 6-side chain favors dimerization mode C,where the amino group of one molecule attacks the β-lactam of another molecule.These findings can lead to a polymer control approach to maintaining penicillin antibiotics in an active formulation.

From a regulatory perspective,drug quality consistency evaluation must concern different processes used for the same drug.In this study,an assessment strategy based on quality by design(QbD)was developed for population pharmaceutical quality evaluation.A descriptive analysis method based on QbD concept was first established to characterize the process by critical evaluation attributes(CEAs).Then quantitative analysis method based on an improved statistical process control(SPC)method was established to investigate the process indicators(PIs)in the process population,such as mean distri-bution,batch-to-batch difference and abnormal quality probability.After that rules for risk assessment were established based on the SPC limitations and parameters.Both the SPC parameters of the CEAs and the risk of PIs were visualized according to the interaction test results to obtain a better understanding of the population pharmaceutical quality.Finally,an assessment strategy was built and applied to generic drug consistency assessment,process risk assessment and quality trend tracking.The strategy demon-strated in this study could help reveal quality consistency from the perspective of process control and process risk,and further show the recent development status of domestic pharmaceutical production processes.In addition,a process risk assessment and population quality trend tracking provide data-based information for approval.Not only can this information serve as a further basis for decision-making by the regulatory authority regarding early warnings,but it can also reduce some avoidable adverse reactions.With continuous addition of data,dynamic population pharmaceutical quality is meaningful for emergencies and decision-making regarding drug regulation.

Objective To establish a severe sepsis/septic shock prognosis prediction model based on randomize forest law (RF model), and to evaluate the prognostic value of this model for patients with severe sepsis/septic shock. Methods 497 patients with severe sepsis/septic shock admitted to intensive care unit (ICU) of Zhejiang Hospital from September 2013 to May 2017 were enrolled. The basic data, vital signs and symptoms, biochemical indexes and blood routine indexes on the 1st, 3rd, 5th day and prognosis were collected. According to the 28-day prognosis, the patients were divided into death group and survival group, and the specific indicators about the prognosis of severe sepsis/septic shock were screened. A RF model was constructed by using the specificity indicators. The assessment effectiveness of RF model, sequential organ failure assessment (SOFA), acute physiology and chronic health evaluation Ⅱ(APACHE Ⅱ) were evaluated by receiver operating characteristic (ROC) curve analysis. Results In 497 cases of severe sepsis/septic shock, 201 cases died, 28-day mortality was 40.4%. ① According to the index difference of death group and survival group, 19 specific parameters of the RF model were selected, which included the age; 24-hour urine output, urea nitrogen (BUN), serum creatinine (SCr), platelet count (PLT) on the 1st day; heart rate (HR), mean arterial pressure (MAP), cyanosis and clammy skin on the 3rd day; temperature, HR, MAP, 24-hour urine output, PLT, fever, cyanosis, dyspneic, clammy skin, piebald on the 5th day. ② ROC curve analysis showed that the area under the ROC curve (AUC) of RF model predicting 28-day mortality was higher than that of SOFA and APACHE Ⅱ score on the 1st, 3rd, 5th day (AUC: 0.836 vs. 0.643, 0.554, 0.766 and 0.590, 0.670, 0.758). The sensitivity of RF model to predict the 28-day mortality was 86.1%, the specificity was 77.0%, the accuracy was 80.7%. Conclusion The evaluation model based on random forest can effectively predict the death risk of 28-day in patients with severe sepsis/septic shock, and its predictive efficiency is better than that of the SOFA and APACHE Ⅱ score.

Objective To establish a high performance size esclusion chromatography (HPSEC) method for the determination of high molecular weight impurities of cefotiam hydrochloride for injection.Methods A TSK G2000 SWXL column(7.8 mm × 30 cm,5μm) was used,the mobile phase consisting of phosphate budder solution [0.1 mol·L-1 disodium hyrogen phosphate-0.1 mol·L-1 sodium dihydrogen phosphate (61:39)],the flow rate was 0.7 mL· min-1,the detection wavelength was 254 nm,the column temperature was 30 ℃,the injection volume was 20 μL,and the concentration of polymers was quantified by external standard method.Results For HPSEC method,the calibration curves were linear in the range of 5.0-25.0 μg·mL-1 for cefotiam,and the LOD and LOQ was 0.1 μg·mL-1 and 0.246 μg· mL-1,the RSD for replicate for injections of reference solution was 0.50％,the sample solution was not stable in room temperature.Conclusion The method has high separation efficiency and good specificity,which provides reference for the further study of the polymer of cefotiam hydrochloride for injection.

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.

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.

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.

Reversed-phase liquid chromatography coupled with electrospray ionization tandem mass spectrometry (ESI-MS/MS) was used to characterize impurities in cefpodoxime proxetil, an ester-modified prodrug. Based on the mechanisms by which cephalosporins are degraded, stress tests were designed and performed. The bulk material and capsule were eluted through a C18 column with formic acid-methanol-water as the mobile phase. In total, 15 impurities were characterized in commercial samples, including 7 known impurities and 8 new impurities. The structures of these unknown compounds were deduced via comparison with the fragmentation patterns of cefpodoxime proxetil. Data from this systematic study will help improve the safety and quality of cefpodoxime proxetil.

Objective: To study whether domestic chloramphenicol eye drops with different ethylparabenin content meet the re-quirements in Chinese Pharmacopoeia. Methods:Antimicrobial effect test was used to examine the antimicrobial effect of the different eye drops. Results:The antimicrobial effect of the eye drops was in compliance with the requirements in the pharmacopoeia. Conclu-sion:The ethylparabenin concentration in the eye drops is higher than necessary. Boric acid and borax not only can adjust pH, but also show antimicrobial effect.