Objective Establishment of a capillary column headspacesampling program for Gas chromatography determination of ethanol residuein Isosorbide Mononitrate sustained-release tablets. Methods A capillarycolumn $\left({{30}\mathrm{\;m}\times {0.320}\mathrm{\;{mm}},{0.25\mu}\mathrm{m}}\right)$ with $6\%$ cyanopropylphenyl-94%dimethylpolysiloxane (or similar polarity) as stationary solution wasused. The starting temperature was ${50}^{\circ }\mathrm{C}$ and maintainedfor $6\mathrm{\;{min}}$ , thetemperature of the detector was ${250}^{\circ }\mathrm{C}$ , thetemperature of the inlet was ${200}^{\circ }\mathrm{C}$ , theequilibrium temperature of the headspace bottle was ${80}^{\circ }\mathrm{C}$ , the equilibriumtime was ${30}\mathrm{\;{min}}$ , theflow rate of nitrogen was $1\mathrm{\;{mL}}/\mathrm{{min}}$ , and thetemperature of the headspace bottle was ${200}^{\circ }\mathrm{C}$ . The shuntratio was ${50}: 1$ . Results Underthe above chromatographic conditions, the retention time of ethanol was $3\mathrm{\;{min}}$ and theconcentration of ethanol was in the range of ${0.43}\sim {10.8\mu}\mathrm{g}/\mathrm{{mL}}$ . The recoveries were ${87.04}\%\sim {94.45}\%,\mathrm{{RSD}}={0.17}\%\left({n = 6}\right)$ .

Against the backdrop of increasingly collaborative global scientific research, regional joint laboratories have gradually gained attention as important platforms for improving research efficiency and transforming achievements. As an effective platform for integrating regional research resources and promoting deep integration of industry, academia, and research, research consortia can play a key role in enhancing regional innovation capabilities of regional joint laboratories and accelerating the transformation of scientific and technological achievements. This article aims to explore the construction and open sharing strategy of regional joint laboratories based on research consortia, analyze the challenges and opportunities faced in the current construction and operation of regional joint laboratories, and propose corresponding countermeasures and suggestions.

Objective To determine the inhibitory effect of skin resident bacteria under the action of different preservatives. Methods Combined with the collected real-time data, the minimum inhibitory concentration value (MIC) was calculated first, the initial constraint conditions were set, and then the bacteria were cultured. The change state of the number of colonies was compared in multiple cycles, and the average value of colony change was calculated to determine and analyze the treatment effect of the bacteria at this time. The test solution was diluted batch by batch, and the inhibition and killing pairs of bacteria were calculated according to the comparison of four test targets: aqueous solution, paste cosmetics, powder cosmetics and liquid cosmetics. Results Under different sample concentration, the resident bacteria of skin were killed and inhibited. After multi-level calculation, the final killing pair value was higher, which could reach more than 7.5. Conclusion The inhibitory effect of increasing the concentration of preservatives on resident bacteria in the skin is basically in a positive change relationship. The higher the concentration of preservatives, the better the inhibitory effect will be formed; conversely, the lower the concentration of preservatives, the relatively poor inhibitory effect will be formed.

The purpose of this paper is to discuss the application of Liquid Chromatography-Mass Spectrometry (LC-MS) in drug quality analysis in order to improve the accuracy and efficiency of drug detection. The basic principle, equipment and application of LC-MS in drug quality analysis are reviewed in this paper. LC-MS technology has shown excellent performance in the qualitative, quantitative, fingerprint and pharmacokinetics of drugs, providing an efficient and accurate tool for drug quality analysis, and has a broad application prospect.

Objective To explore the pathogenic microbial detection results and drug susceptibility results of children with bacterial diarrhea after the collection of stool samples. Methods From April 2020 to June 2023,170 children with bacterial diarrhea participated in the study. The family members were informed about the study, and assisted the children to complete the collection of stool specimens. All the specimens were sent to the laboratory for pathogen culture, counted the distribution of pathogens, and analyzed the drug resistance of pathogens. Results 170 stool samples isolated 122 pathogenic strains, The detection rate of gram-negative bacteria was 76.23%, mainly Salmonella (27.87%), diarrheagenic Escherichia coli (21.31%), Shigella (21.31%); The detection rate of gram-positive bacteria was 23.77%, mainly Staphylococcus aureus (22.95%); Most resistance to tetracycline (41.18%), ciprofloxacin (38.24%), ampicillin (35.29%), The greatest resistance to ciprofloxacin (46.15%), tetracycline (38.46%), of ciprofloxacin (53.85%), tetracycline (46.15%), Staphylococcus aureus had to clindamycin (53.57%) and penicillin (53.57%). Conclusion Salmonella, Escherichia coli, Shigella and Staphylococcus aureus are the main causes of bacterial diarrhea in children. The drug resistance and the choice of sensitive drugs are conducive to the early recovery of children.

Food contaminants pose a serious challenge to public health and the food industry, and there is an urgent need to develop more advanced detection techniques and updated prevention strategies. Although the traditional culture technology has played an important role in the detection of food contaminants, there are obvious limitations in the detection speed, sensitivity and specificity. With the increasing expansion of global food trade, the growing production scale of food enterprises, and the increasing attention of the public to food safety, food safety has become a hot topic around the world. Food contaminants are mainly divided into chemical and biological categories, including but not limited to pesticide and veterinary drug residues, heavy metal ions, abused food additives, foodborne pathogens and mycotoxins. In recent years, with the rapid development of cutting-edge technologies such as molecular biology technology, biosensors, nanotechnology and advanced imaging technology, these innovative methods are gradually overcoming the limitations of traditional detection methods. This paper discussed the principles, advantages and limitations of these innovative detection technologies in depth, and reviewed the latest research progress in the field of food detection. By comparing different detection methods, this paper aims to provide guidance for selecting suitable detection technology to achieve rapid and accurate detection and analysis of food contaminants.

Objective To establish a method for the detection of cyclicaldehyde compounds in drinking water sources, in order to practice highquality development and improve the technical support of public servicequality. Methods Quantitative detection method of cyclic aldehydecompounds in drinking water by using SPME-GC-MS/MS were established.Results The results show that the optimal conditions for SPME aimed atcyclic aldehyde compounds in drinking water are an incubationtemperature of ${50}^{\circ }\mathrm{C}$ , a rotationalspeed of ${500}\mathrm{r}/\mathrm{{min}}$ , anincubation duration of ${15}\mathrm{\;{min}}$ , followed by asample extraction time of ${20}\mathrm{\;{min}}$ . The detectionlimits of this quantitative detection method were 2.87~4.67 ng/ L, therelative standard deviation were 6%~16%, the recoveries were 70.7%~115%.A specific water sample was collected to ascertain that the keyodor-causing compound was2-EDD, exhibiting concentrations ${32}\mathrm{{ng}}/\mathrm{L}$ . Conclusion This method can accurately and swiftly identify key odor-causingcompounds in drinking water.

As important bases for experimental teaching and medical research, the biosecurity of laboratories in medical universities cannot be ignored. In order to accurately grasp the research progress of biosecurity management in medical university laboratories in China, co-word cluster analysis was conducted on the 473 literatures related to biosecurity in medical laboratories published in the CNKI database from 2004 to 2023 using CiteSpace software. The research results showed that biosecurity, laboratory safety management, safety education, and medical testing are the four current research hotspots in this field, while medical research laboratories and safety education are potential directions for future research development.

Lactic acid and its derivatives are important flavor substances in Nongxiang Baijiu which play a vital role in the aroma and taste of the wine. In order to screen lactic acid bacteria, this study tooke a Nongxiang Baijiu fermented grains as the research object. The isolation conditions of lactic acid bacteria were optimized, the effects of different DNA extraction methods were compared, and the species of lactic acid bacteria were identified by enzyme digestion and DNA sequencing. The results showed that 95 strains of lactic acid bacteria were preliminarily screened in MRS broth medium under anaerobic culture at 37°C for 24 h. The optimal method for DNA extraction of lactic acid bacteria was determined to be boiling method, and the strains were identified as Lactobacillus panis, which had the effects of producing lactic acid and n-propanol. This study has important reference value for the production and quality improvement of Nongxiang Baijiu.

Scientific research and experimental teaching are the main functions of university laboratory. Therefore, university laboratory plays an important role in personnel training and scientific research and development. However, many kinds of chemicals are stored in university laboratories, and some of them have the characteristics of being flammable and explosive, which increases the risk of accidents in university laboratories and easily threatens the safety of students and teaching staff, therefore, colleges and universities should pay attention to the laboratory safety management and control work, timely detection of security risks, improve laboratory safety. This paper describes the current situation of laboratory management in colleges and universities, and puts forward some safety control measures to provide reference for laboratory management.