Uncovering the Shuixian tea grades hierarchy in Chinese national standard: From sensory evaluation to microstructure and volatile compounds analysis.

Basic standard samples are integral for ensuring consistency and quality control of tea. Understanding the real reasons behind the hierarchical system of Shuixian tea grades in the Chinese national standard is crucial to the scientific development of tea standardization. In this investigation, different grade samples of Shuixian tea strictly conformed to the Chinese national standard, serving as the research objects. Sensory evaluation, SEM and HS-SPME-GC-MS were employed to comprehensively analyze the aroma characteristics. The odor profiles of special grade samples predominantly featured floral and fruity aromas, which attributed to compounds such as geraniol, indole, phenylethyl alcohol. Additionally, hexanal, (E)-3-hexen-1-ol and other compounds contributed to fruity and sweet aroma in first grade. Notably, the predominant roasted and sweet aromas of second grade were attributed to compounds including pyridine, 2,5-dimethyl-pyrazine. This study lays a solid foundation for the scientific development of Chinese national standards and international standard system.

Analysis on the location of scalp acupuncture lines based on the 2021 version of Standardized Manipulations of Acupuncture and Moxibustion--Part 2： Scalp Acupuncture. / 2021版《针灸技术操作规范（第2部分）：头针》头穴线定位疑析.

In order to better promote the popularization and application of the national standard of Standardized Manipulations of Acupuncture and Moxibustion--Part 2： Scalp Acupuncture (GB/T 21709.2-2021), and to provide reference for the improvement and formulation of the next version, in the present paper, the differences about the position descriptions of two scalp acupuncture lines Dingnie Qianxiexian (anterior oblique line of vertex-temporal, MS6) and Dingpangxian 1 (lateral line 1 of vertex, MS8) between the new (GB/T 21709.2-2021) and old (GB/T 21709.2-2008) versions of the national standards as well as the International Standard Proposal of Scalp Acupuncture Point were compared, and the disputes still existing in the 2021 version were discussed. Although the 2021 version has made relevant amendments in some controversial or non-standard contents in the 2008 version, there are still some inappropriate contents. Firstly, only the relevant revision in the attached figure 3 was mentioned in the preface, without mention of the word revision about MS6 in both English and Chinese, but actually "Chengguang" (BL6) has been changed to "Tongtian" (BL7). Secondly, The attached figure does not match the word description. There is a revision in the attached figure and text at the same time, in which the text description of Qianding (GV21) of the MS6 has not been revised, but the front Shencong (EX-HN1) in the attached figure has been changed to GV21, which is obviously inconsistent with the positioning of the MS6 according to the WHO international standard, and the basis for the revision is not known. These revisions of the 2021 version of national standard on the position of the two scalp acupoint lines in the 2008 version are inconsistent, which may make many colleagues in the acupuncture field confused. Thus, further revision is necessary.

[Discussion on the application status and method improvement of gas chromatography in occupational health inspection standards in China].

As a rapid, accurate and efficient analytical technique, gas chromatography is widely used in the detection of volatile organic compounds and inorganic small molecule toxins, and it is the main analytical method in the national testing standards for occupational health. The existing effective national standards of gas chromatography for the detection of some substances have low column efficiency, high toxicity of reagents, poor correlation of the standard curve and low desorption efficiency and other problems, some of which can be solved through method improvement. At the same time, with the use of new materials and new processes, new types of toxic substances are emerging, and there are still many occupational disease hazards of limited value without supporting detection methods, gas chromatography can be applied to the detection of some toxic substances to better complement the vacancy of China's occupational health detection methods. This paper analyzes the current situation of the application of gas chromatography in occupational health testing standards, discusses the improvement of some of these methods, and helps to promote the application and development of gas chromatography in occupational health testing.

Establishment and Characterization of the First Chinese National Standard for Nucleic Acid Amplification Technology Assays for Hepatitis E Virus Nucleic Acid Detection.

The detection of hepatitis E virus (HEV) RNA is the gold standard for HEV infection diagnosis. In order to address the quality control requirements for HEV RNA detection kits within China, we aimed to establish the first Chinese national standard for HEV RNA detection through a collaborative study. The candidate standard was quantified using digital PCR (dPCR). A total of five laboratories were invited to determine the estimated mean value of this national standard relative to the World Health Organization International Standard (WHO IS). Additionally, four commercial kits were used to assess the applicability of the candidate standard. The stability was determined by freeze-thaw cycles and storage at 37 °C, 25 °C and 4 °C. The estimated mean value of this national standard relative to the WHO IS was 5.67 log10 IU/mL. Two out of the four commercial kits can detect as low as the estimated limit of detection (LOD). The degradation rates of samples in the stability study ranged from 4% to 19%. In conclusion, we have established the first Chinese national standard for HEV nucleic acid detection against WHO IS, which can be employed to evaluate the quality of HEV RNA detection kits.

A collaborative study to establish the second national standard for hepatitis B immunoglobulin in Korea.

This study aimed to establish a second national standard for hepatitis B immunoglobulin (HBIG) that can be used for potency assays of hepatitis B and normal immunoglobulin. The candidate material was manufactured using a process approved as Good Manufacturing Practice. The freeze-dried candidate preparation was tested for physicochemical and biological properties, including pH, residual moisture, molecular size distribution, and potency. A collaborative study was performed involving four laboratories, including the National Institute of Food and Drug Safety Evaluation, as an official national control laboratory in Korea and manufacturers. The potency was calibrated against the second international standard for HBIG using two enzyme immunoassays: enzyme-linked immunosorbent assay and electrochemiluminescence immunoassay. Results from 240 assays were obtained from four laboratories, and combined potency estimates were obtained by calculating the geometric means. Intra- and inter-laboratory variability showed acceptable geometric coefficients of variation of 1.3-6.0 and 3.2-3.6%, respectively. The candidate preparation showed satisfactory stability in accelerated thermal degradation and real-time stability tests. Based on these results, the potency value of 105 IU/vial was assigned (95% confidence intervals: 100.0-109.2 IU/vial), and it was deemed suitable to serve as the Korean national standard for HBIG.

Establishment of national standard for anti-SARS-Cov-2 neutralizing antibody in China: The first National Standard calibration traceability to the WHO International Standard.

Neutralizing antibody (NtAb) levels are key indicators in the development and evaluation of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) vaccines. Establishing a unified and reliable WHO International Standard (IS) for NtAb is crucial for the calibration and harmonization of NtAb detection assays. National and other WHO secondary standards are key links in the transfer of IS to working standards but are often overlooked. The Chinese National Standard (NS) and WHO IS were developed by China and WHO in September and December 2020, respectively, the application of which prompted and coordinated sero-detection of vaccine and therapy globally. Currently, a second-generation Chinese NS is urgently required owing to the depletion of stocks and need for calibration to the WHO IS. The Chinese National Institutes for Food and Drug Control (NIFDC) developed two candidate NSs (samples 33 and 66-99) traced to the IS according to the WHO manual for the establishment of national secondary standards through a collaborative study of nine experienced labs. Either NS candidate can reduce the systematic error among different laboratories and the difference between the live virus neutralization (Neut) and pseudovirus neutralization (PsN) methods, ensuring the accuracy and comparability of NtAb test results among multiple labs and methods, especially for samples 66-99. At present, samples 66-99 have been approved as the second-generation NS, which is the first NS calibrated tracing to the IS with 580 (460-740) International Units (IU)/mL and 580 (520-640) IU/mL by Neut and PsN, respectively. The use of standards improves the reliability and comparability of NtAb detection, ensuring the continuity of the use of the IS unitage, which effectively promotes the development and application of SARS-CoV-2 vaccines in China.

Epidemiology of in-hospital cardiac arrest patients admitted to the intensive care unit in Australia: a retrospective observational study.

BACKGROUND: In-hospital cardiac arrest (IHCA) affects approximately 3000 patients annually in Australia. Introduction of the National Standard for Deteriorating Patients in 2011 was associated with reduced IHCA-related intensive care unit (ICU) admissions and reduced in-hospital mortality of such patients. AIMS: To assess whether the reduction in IHCA-related ICU admissions from hospital wards seen following the implementation of the national standard (baseline period 2013-2014) was sustained over the follow-up period (2015-2019) in Australia. METHODS: A multi-centre retrospective cohort study to compare the characteristics and outcomes of IHCA admitted to the ICU between baseline and follow-up periods. The primary outcome was the proportion of patients admitted to ICU from the ward following IHCA. Secondary outcomes included ICU and hospital mortality of IHCA-related ICU admissions. Data were analysed using hierarchical multivariable logistic regression. RESULTS: The proportion of cardiac arrest-related admissions from the ward was lower in the follow-up period when compared to baseline (4.1 vs 3.8%; P = 0.04). Such patients had lower illness severity and were more likely to have limitations of medical treatment at admission. However, after adjustment for severity of illness, the likelihood of being admitted to ICU following cardiac arrest on the ward increased in the follow-up period (odds ratio (OR) 1.13 (1.05-1.22); P = 0.001). Hospital mortality was lower in the follow-up period (50.3 vs 46.3%; P = 0.02), but after adjustment the likelihood of death did not differ between the periods (OR 1.0 (0.86-1.17); P = 0.98). CONCLUSION: After adjustment for the severity of illness, the likelihood of being admitted to ICU after IHCA slightly increased in the follow-up period.

Establishment of the 1st Chinese national standard for CA6 neutralizing antibody.

Coxsackievirus A6 (CA6) is one of the major causative agents of herpangina and hand-foot-mouth disease (HFMD). Since 2008, CA6 has circulated widely around the world. Especially in Asia-Pacific region CA6 had even replaced enterovirus A71 (EV71) and coxsackievirus A16 (CA16) as the main prevalent strain of HFMD. In the recent 10 years, monovalent and multivalent vaccines against CA6 have been researched and developed by manufacturers from China, Korea, and the USA. The neutralizing antibody titer is a key indicator for accurately evaluating immunogenicity of vaccine. However, so far, the World Health Organization international standard for CA6 neutralizing antibody has not been available. In order to meet the needs of evaluating the immunogenicity of vaccines against CA6, the first Chinese national standard for CA6 neutralizing antibody was established, which was conducted to ensure that methods used to measure the neutralizing antibody titers against CA6 are accurate, reliable, and comparable. Three lyophilized candidate standards (29#, 39# and 44#) were produced with 0.40 ml/vial from plasma samples donated by healthy individuals. The collaborative study showed that the 29# candidate standard could effectively minimize the variability in neutralization titers between labs and across challenging viruses of different genotypes (A, D1, and D3). Therefore, the 29# candidate sample was established as the first Chinese national standard for CA6 neutralizing antibody test. This standard has good long-term stability and was assigned a potency of 150 units per milliliter (U/ml) of CA6 neutralizing antibody. It will contribute to ensure uniformity of potency or activity of vaccines and potentially therapeutic antibody preparations.

Laparoscopic Adrenalectomy Is Beneficial for the Health-Related Quality of Life of Older Patients with Primary Aldosteronism.

OBJECTIVE: Laparoscopic adrenalectomy (LADX) improves hypertension in patients with primary aldosteronism (PA). However, the antihypertensive impact of LADX appears restricted in older patients with PA. In this study, we evaluated the impact of LADX in older patients focusing on the health-related quality of life (HRQoL). METHODS: A total of 156 patients with PA who underwent LADX in a single institution were enrolled in this prospective cohort study. The patients were divided into 2 groups, with a boundary of 60 years. The HRQoL was evaluated using the Medical Outcomes Study's 36-Item Short-Form Health Survey version 2 (SF-36v2) questionnaire before and after LADX. Demographics, clinical features, antihypertensive drugs before and after surgery, and perioperative evaluation were recorded. We compared all scale scores and summed scores between groups. Multivariate regression models were used to determine the associations between various covariables and the HRQoL. RESULTS: In the older PA patients, most subscales of HRQoL at baseline were lower than the national standard values. The antihypertensive drug-free rate by LADX was only 21% in older patients, compared to 58% in younger patients. However, a significant improvement in mental HRQoL was observed after LADX (p = 0.002). The much preoperative antihypertensive drugs, lower preoperative potassium level, and smaller degree of comorbidities were predictors of improved mental HRQoL by LADX on multivariate analyses. CONCLUSION: The older PA patients showed lower mental HRQOL than the national standard populations. Although antihypertensive effects were limited for these patients, LADX was beneficial as PA treatment via improvement of mental HRQoL.

Development of national standards for genomic titer determination of recombinant type 5 adeno-associated virus / 中国生物制品学杂志

@#ObjectiveTo develop a national standard for genomic titer determination of recombinant type 5 adeno-associated virus(rAAV5).MethodsThe rAAV5-GFP stock solution prepared by the three-plasmid system was identified and verified for the appearance,pH,sterility,genomic titer,purity and infection titer according to the relevant requirements of Chinese Pharmacopoeia(Volume Ⅲ,2020 edition),which was diluted and subpackaged to prepare candidate standards according to the results;The stability of candidate standards was investigated by thermal acceleration test;Three laboratories were organized to collaboratively calibrate the candidate standards using droplet digital PCR(ddPCR).ResultsAll the detection indexes of the candidate standard and the stock solution met the relevant requirements;The genomic titer showed no significant decrease at 25,4,-20,-40,-80 ℃ for 1,3,4,6 months;Through collaborative calibration by three laboratories,the candidate standard was assigned a value of 2. 56 × 10(12)copies/mL,and the 95% confidence interval was 2. 48 ×10(12)copies/mL,and the 95% confidence interval was 2. 48 ×10(12)copies/mL ～ 2. 64 × 10(12)copies/mL ～ 2. 64 × 10(12)copies/mL.ConclusionThe developed national standard for the determination of rAAV5 genomic titer had good stability and might be used for the quality evaluation of rAAV5 related products.

Collaborative calibration of the 9th national standard for human rabies vaccine / 中国生物制品学杂志

@#Objective To collaboratively calibrate and finally assign the potency of the 9th national standard for human rabies vaccine for candidate.Methods Qualified laboratories for the production,research and development of human rabies vaccines were organized to determine the potency of candidate national standard for rabies vaccines by using NIH method,with the 7th international standard for rabies vaccines(NIBSC code:16/204)as the reference standard. The detection results were statistically analyzed,and the geometric mean of effective detection values was taken as the final potency value of the candidate standard. According to the requirements of the preparation of national drug reference materials,the candidate standard was destroyed by heat acceleration,and then detected for the glycoprotein antigen to investigate the stability.Results A total of 20 laboratories participated in the collaborative calibration,of which the two laboratories that did not strictly follow the collaborative calibration SOP were excluded,and the data of the remaining collaborative laboratories were valid. After statistical analysis,the final potency of the 9th national standard for rabies vaccine was 11. 4 IU/mL,the 95% confidence limit was 10. 9～11. 9 IU/mL,and the 95% reference range of ED_(50) was 2. 10～2. 75. There was no significant difference in the results of glycoprotein antigen detection under different time conditions(2,4,8 and 16 weeks)at 37 ℃.Conclusion The collaborative calibration research of the 9th national standard for human rabies vaccine(batch number:201906001)has been completed,the potency assignment is scientific and rigorous,the data was reliable,and the thermal stability meets the requirements. At present,this standard has been approved by the National Drug Reference Material Committee,which is of great significance to the quality control of human rabies vaccine,especially the quality control of effectiveness.

Effect of cryopreservation on biological activity of national standard of human granulocyte colony-stimulating factor after reconstitution / 中国生物制品学杂志

@#ObjectiveTo investigate the effect of cryopreservation on the biological activity of the national standard of human granulocyte colony-stimulating factor(hG-CSF)after reconstitution,so as to provide a reference for the use of the national standard of hG-CSF.MethodsThe biological activity of the standard was determined according to the general rule 3525 of Chinese Pharmacopoeia(Volume Ⅲ,2020 edition);The reconstituted hG-CSF national standard was aliquoted and stored at-80 ℃,-40 ℃ and-20 ℃,and then sampled at 1,2,3,5 and 6 months to detect the biological activity. The standards reconstituted before use were used to quantify the standards stored at -80 ℃ for different time durations,and the standards stored at -80 ℃ were defined as the reference of 100% activity to quantify the relative biological activity of the other samples.ResultsThe Eyrlng equation fitted by the thermal acceleration stability experiment was:ln {k(t)} = 6. 75-3 772. 20/T + ln(T),R~2= 0. 969. The biological activity of hG-CSF national standard was predicted to decrease by 5% after about 93. 4 months storage at -80 ℃；The biological activity of reconstituted standards frozen at -80 ℃ decreased by about 24%.ConclusionThe aliquoted reconstituted hG-CSF national standard can be stored at -80 ℃ stably for more than half a year. However,freezing and thawing will cause the activity value to drop by more than 20%,so it is not recommended to reuse after reconstitution.

Discussion on application of control level of radioactive contamination on personnel′s body surface in a nuclear and radiological emergency / 中华放射医学与防护杂志

There are differences and inconsistencies to some degree in the radioactive contamination control level of personnel′s body surface availiable in many national standards, thus puzzling the users. Therefore, it is proposed to compare the applicable scope, conditions and differences between relevant national standards, and combine with similar clinical nuclear medicine standards of radiological protection content to presevent recommendations on the contamination control level that should be correctly applied in an event of nuclear and radiological emergency. Based on the discussion of similar standards, the contaminated personnel with α of 0.04-10 Bq/cm 2 and β of 0.4-100 Bq/cm 2 are advised to be treated in the institutions with higher than secondary medical insititution. Both α econtamination control levels less than 0.04 Bq/cm 2 and β levels less than 0.4 Bq/cm 2 could be achivable, if fully decontaminated.

Utilising cumulative antibiogram data to enhance antibiotic stewardship capacity in the Cape Coast Teaching Hospital, Ghana.

BACKGROUND: Antimicrobial resistance (AMR) is a major public health challenge with its impact felt disproportionately in Western Sub-Saharan Africa. Routine microbiology investigations serve as a rich source of AMR monitoring and surveillance data. Geographical variations in susceptibility patterns necessitate regional and institutional tracking of resistance patterns to aid in tailored Antimicrobial Stewardship (AMS) interventions to improve antibiotic use in such settings. This study focused on developing a cumulative antibiogram of bacterial isolates from clinical samples at the Cape Coast Teaching Hospital (CCTH). This was ultimately to improve AMS by guiding empiric therapy. METHODS: A hospital-based longitudinal study involving standard microbiological procedures was conducted from 1st January to 31st December 2020. Isolates from routine diagnostic aerobic cultures were identified by colony morphology, Gram staining, and conventional biochemical tests. Isolates were subjected to antibiotic susceptibility testing using Kirby-Bauer disc diffusion. Inhibitory zone diameters were interpreted per the Clinical and Laboratory Standards Institute guidelines and were entered and analysed on the WHONET software using the "first isolate only" principle. RESULTS: Overall, low to moderate susceptibility was observed in most pathogen-antibiotic combinations analysed in the study. Amikacin showed the highest susceptibility (86%, n = 537/626) against all Gram-negatives with ampicillin exhibiting the lowest (6%, n = 27/480). Among the Gram-positives, the highest susceptibilities were exhibited by gentamicin (78%, n = 124/159), with clindamycin having the lowest susceptibility (27%, n = 41/154). Among the Gram-negatives, 66% (n = 426/648) of the isolates were identified phenotypically as potential extended-spectrum beta-lactamase producers. Multiple multidrug-resistant isolates were also identified among both Gram-positive and Gram-negative isolates. Low to moderate susceptibility was found against first- and second-line antibiotics recommended in the National standard treatment guidelines (NSTG). Laboratory quality management deficiencies and a turnaround time of 3.4 days were the major AMS barriers identified. CONCLUSIONS: Low to moderate susceptibilities coupled with high rates of phenotypic resistance warrant tailoring NSTGs to fit local contexts within CCTH even after considering the biases in these results. The cumulative antibiogram proved a key AMS programme component after its communication to clinicians and subsequent monitoring of its influence on prescribing indicators. This should be adopted to enhance such programmes across the country.

A collaborative study to establish the national standard for SARS-CoV-2 RNA nucleic acid amplification techniques (NAAT) in Taiwan.

The conventional PCR remains a valuable method to detect the newly emergent coronavirus rapidly and accurately. Our investigation aimed to establish the standard materials of SARS-CoV-2 for NAAT detection. We provided formalin-inactivated SARS-CoV-2 and confirmed RNA copy numbers. In addition, the virus genome was confirmed with whole-genome sequencing and identified as Wuhan/WI04/2019. Seven laboratories were invited for this collaborative study, according to the reporting data, we determined the SARS-CoV-2 with the unit of 6.35 Log10 copies/mL as the national standard. The availability of the national standard (NS) of SARS-CoV-2 will facilitate the standardization and harmonization of SARS-CoV-2 NAAT assays.

[Specification and solution of the normative elements in the development of the national standard: "Pure moxa stick"].

This paper introduced the research ideas and methods for the development of the national standard, "Pure moxa stick". According to the orientation of product standard and related documents, on the basis of extensive investigation and in consultation with manufacturers and experts, the problems encountered in this standard development were solved. The general technical requirements were specified in association with the basic experimental data. The technical requirements should not only conform to the current technological status of moxa sticks production, but also present a certain of innovation. The innovation of this standard lies in the concepts of the ratio of leaves to floss, the ratio of whole plant to floss, density, etc. Besides, the main technical requirements of "Pure moxa stick" have been specified, i.e. material, shape and structure, combustion characteristics, physical and chemical characteristics. The development of national standard "Pure moxa stick" contributes to the favorable exploration and practice of the standardization of traditional Chinese medicine and provides the effective reference for the further stan-dardization of acupuncture and moxibustion.

Considerations for the Feasibility of Neutralizing Antibodies as a Surrogate Endpoint for COVID-19 Vaccines.

To effectively control and prevent the pandemic of coronavirus disease 2019 (COVID-19), suitable vaccines have been researched and developed rapidly. Currently, 31 COVID-19 vaccines have been approved for emergency use or authorized for conditional marketing, with more than 9.3 billion doses of vaccines being administered globally. However, the continuous emergence of variants with high transmissibility and an ability to escape the immune responses elicited by vaccines poses severe challenges to the effectiveness of approved vaccines. Hundreds of new COVID-19 vaccines based on different technology platforms are in need of a quick evaluation for their efficiencies. Selection and enrollment of a suitable sample of population for conducting these clinical trials is often challenging because the pandemic so widespread and also due to large scale vaccination. To overcome these hurdles, methods of evaluation of vaccine efficiency based on establishment of surrogate endpoints could expedite the further research and development of vaccines. In this review, we have summarized the studies on neutralizing antibody responses and effectiveness of the various COVID-19 vaccines. Using this data we have analyzed the feasibility of establishing surrogate endpoints for evaluating the efficacy of vaccines based on neutralizing antibody titers. The considerations discussed here open up new avenues for devising novel approaches and strategies for the research and develop as well as application of COVID-19 vaccines.

[Interpretation of China national standard Nomenclature and Location of Meridian Points (GB/T 12346-2021)].

To cooperate with the popularization and application of the China national standard Nomenclature and Location of Meridian Points (GB/T 12346 -2021), this study introduced the differences between the 2021 version and the 2006 version, and explained the principles of the revision and the changes in the standard name, terminology, definition and the expression of meridian points' body regions. In addition, the revision of the specific contents, including the adjustment of "bone proportional cun" of several meridian points and the revision basis of location of some meridian points were explained.

[Consideration on development of the national standard: Pure Moxa Stick].

The paper gives a consideration on the development of the national standard, Pure Moxa Stick. It is proposed that the principle and requirements for the development of product standard should be adhered to, while focusing on the applicability and safety of pure moxa stick. In terms of quality, the specific requirements should be developed on the ratio of moxa floss, wrapping paper and adhesives. Regarding the specifications, either the market demands or the resource waste prevention should be considered. In safety, the combustion temperature and moxa smoke control are the key issues.

Establishment of the first Chinese national standard for protein subunit SARS-CoV-2 vaccine.

A reference standard is needed for quality control of protein subunit SARS-CoV-2 vaccines to meet urgent domestic needs. The Chinese National Institutes for Food and Drug Control (NIFDC) launched a project to establish the first reference material for the protein subunit SARS-CoV-2 vaccine to be used for calibration of antigen testing. The potency and stability of the national candidate standard (CS) were determined by collaborative calibration, and accelerated and freeze-thaw degradation studies. Moreover, a suitability study of the CS was performed. Eight laboratories in mainland China were asked to detect antigen content of CS using a common validated enzyme-linked immunosorbent assay (ELISA) kit established by NIFDC and in-house kits in the collaborative study. Six laboratories returned valid results, which established that the antigen content of the CS was 876,938 YU/mL, with good agreement across laboratories. In the suitability study, the CS exhibited excellent parallelism and a linear relationship with four samples produced by different expression systems and target proteins. In addition, good stability in the accelerated and freeze-thaw degradation study was observed. In conclusion, the CS was approved by the Biological Product Reference Standards Sub-Committee of the National Drug Reference Standards Committee as the first Chinese national standard for determining antigen content of protein subunit SARS-CoV-2 vaccines, with an assigned antigen content of 877,000 U/mL (Lot. 300050-202101). This standard will contribute to a standardized assessment of protein subunit SARS-CoV-2 vaccine in China and may provide experience for developing reference materials for antigen content detection of SARS-CoV-2 vaccine in other countries.