OBJECTIVETo develop a solvent desorption gas chromatographic method for determination of n-pentanol in the workplace air.

METHODSn-Pentanol in the workplace air was collected with activated carbon tubes, desorbed with 2% 2-propanol in carbon disulfide, separated with a nitroterephthalic acid-modified FFAP capillary column, and detected with flame ionization detector.

RESULTSThe limit of detection was 0.2 mg/L; the lower limit of quantification was 0.6 mg/L; the linear range was 0.6-4072.0 mg/L. The minimum detectable mass concentration was 0.2 mg/m3 for 1.5 L of air sample. This method was highly repeatable. The relative standard deviations were 2.3%-5.4%. The average desorption efficiencies were 86.9%-94.2%. The absorption efficiencies were 100%. The breakthrough volume was above 8.0 mg in 100-mg activated carbon. The samples in activated carbon tubes could be stored for at least 14 days at room temperature.

CONCLUSIONThe method is feasible for determination of n-pentanol in the workplace air.

2-Propanol ; Air Pollutants, Occupational ; analysis ; Carbon Disulfide ; Charcoal ; Chromatography, Gas ; Limit of Detection ; Pentanols ; analysis ; Solvents ; Workplace

Environmental Monitoring ; methods ; Gas Chromatography-Mass Spectrometry ; methods ; Humans ; Industry ; Volatile Organic Compounds ; analysis

Objective: To establish a solvent desorption gas chromatographic method for determination of Sevoflurane, Isoflurane and Enflurane in the air of the Workplace. Methods: Sevoflurane, Isoflurane and Enflurane were collected with activated carbon tube and desorbed with dichloromethane, separated with DB-1 capillary columns, and then detected with flame ionization detector. Results: The linearity ranges were 1.9-304.8 μg/ml for Sevoflurane, 2.1-300.4 μg/ml for Isoflurane and 1.7-305.2 μg/ml for Enflurane, The correlation coefficient was both >0.999. Their limits of detection were 0.6 μg/ml, 0.6 μg/ml and 0.5 μg/ml, and Their limits of quatification were 1.9 μg/ml, 2.1 μg/ml and 1.7 μg/ml, and their minimum detectable concentrations were 0.1、0.2 and 0.1 mg/m³ per 4.5 L of air. Their relative standard deviations (RSD) were 2.5%-3.0%, 2.3%-3.1% and 2.2%-3.0%. The average desorption efficiencies were 101.1%-103.3%, 100.7%-102.7% and 101.0%-102.9%. The sampling efficiency was both 100%. The breakthrough volume of 100 mg actived carbon was 3.7 mg, 3.4 mg and 3.4 mg. Sevoflurane, Isoflurane and Enflurane in activated carbon tube could be kept at least 10 days at room temperature without significant losses. Conclusion The method shows lower detection limit, high accuracy and precision. It is feasible for determination of Sevoflurane, Isoflurane and Enflurane in the air of workplace.

Objective:To investigate the effects of docetaxel, Carboplatin combined with radical cervical cancer surgery on the expression of serum tumor markers and Th1/Th2 cytokines in patients with cervical cancer.Methods:96 patients with cervical cancer from Aug. 2018 to Aug. 2020 were selected as the study subjects. They were randomly divided into operation group and chemotherapy + operation group according to random number table method. Surgical group underwent radical hysterectomy (laparoscopic hysterectomy + pelvic lymph node dissection), chemotherapy + surgery group received docetaxel + Carboplatin adjuvant chemotherapy before operation. Serum tumor markers [CEA, CA125, CA19-9, squamous epithelium fine] were compared between the two groups. The expression of SCC, Th1/Th 2 cytokines [IFN-gamma, IL-2, IL-4, IL-6] and the occurrence of bone marrow suppression were evaluated.Results:There was no significant difference in serum CEA, CA125, CA19-9 or SCC between the two groups before treatment ( P>0.05), but they were significantly decreased after treatment ( P<0.05). After treatment, IFN-γ [ (20.58±3.52) ; (25.69±3.61) ] and IL-2 [ (24.68±4.46) ; (29.53±5.28) ] were significantly increased in the two groups ( P<0.05). IL-4 [ (17.65±4.12) ; (13.59±4.23) ] and IL-6 [ (24.59±3.85) (31.76±4.42) ] were significantly decreased ( P<0.05). IFN-γ and IL-2 in the acupuncture group were significantly higher than those in the operation group ( P<0.05). IL-4 and IL-6 were significantly lower than those in the operation group ( P<0.05), and serum CEA [ (33.89±5.51) ng/L; (30.46±4.86) ng/L], CA125, CA19-9 [ (42.21±5.23) U/mL; (37.56±5.61) U/mL] and SCC [ (1.12±0.12) μg/mL; (0.96±0.15) μg/mL] were significantly decreased ( P<0.05). The chemotherapy group was significantly lower than the surgery group ( P<0.05), and the effective rate of chemotherapy group was significantly higher than that of the operation group ( P<0.05), and there was no significant difference in myelosuppression between the two groups ( P>0.05) . Conclusion:Docetaxel plus Carboplatin adjuvant chemotherapy before radical operation of cervical cancer can significantly improve the clinical efficacy, reduce the level of serum tumor markers, improve immune function, and do not increase adverse reactions. It is worth promoting.

Objective:To establish a method for determining mercury in blood with direct mercury analyzer.Methods:After the whole blood sample was extracted by solvent and removed by nitric acid, it was then measured by direct mercury analyzer.Results:After optimizing the conditions of the instrument, the linear range was 0.3-60.0 μg/L and the curve correlation coefficient was higher than 0.999. The lower limit of quantitations was 0.3 μg/L and the minimum quantitative concentration was 3.0 μg/L. The recovery and relative standard deviations ( RSD) was 95.2%-97.6% and 1.4%-3.3%. Conclusion:The method is stable, reliable, easy to operate and has high sensitive. It can be used to determine mercury in blood.

Objective:To establish a method for determining mercury in blood with direct mercury analyzer.Methods:After the whole blood sample was extracted by solvent and removed by nitric acid, it was then measured by direct mercury analyzer.Results:After optimizing the conditions of the instrument, the linear range was 0.3-60.0 μg/L and the curve correlation coefficient was higher than 0.999. The lower limit of quantitations was 0.3 μg/L and the minimum quantitative concentration was 3.0 μg/L. The recovery and relative standard deviations ( RSD) was 95.2%-97.6% and 1.4%-3.3%. Conclusion:The method is stable, reliable, easy to operate and has high sensitive. It can be used to determine mercury in blood.

Objective: To establish a method for determination of acetone, dichloromethane, hexane, 1, 1, 1-trichloroethane, 1, 2-dichloroethane, benzene, toluene, ethylbenzene etc organic compounds in urine by headspace gas chromatography-mass spectrometry (GC-MS) . Methods: Headspace gases of urine samples were injected into GC and determined by mass. Results: Determination of urine components were in a good linear range in their concentration range of this method. The correlation coefficients were between 0.996 and 1.000 with the detection limits between 0.1 μg/L and 4.5 μg/L, the precisions were between 1.3% and 4.6%, the recovery rates were between 86.2% and 97.4%. Conclusion This method has the advantages of low detection limits, high accuracy, high precision and simple pretreatment, which is suitable for the determination of the content of various volatile organic compounds in urine.

Objective: To develop a method for determination of metabolites of diphenylmethane diisocyanate (MDI) in urine, i.e. methylenedianiline (MDA) by high performance liquid chromatography-tandem mass (LC-MS-MS) . Methods: Urine samples were prepared by hydrolyzation with sulfuric acid and extraction by acetonitrile, and then separated on a Shim-pack XR-ODS column, analyzed with high-performance liquid chromatography-tandem mass spectrometry (LC-MS/MS) . The external solvent standard calibration were tested. Results: The linearity ranges were 0.05~20.00 μg/L, The related coefficients were 0.999 5. The limit of detection was 0.02 μg/L. The rats of recovery were 91.0%~103.4%. The relative standard deviations were between 2.7%~7.3%. Conclusion The method was sensitive, accurate and suitable for the MDA determination in urine of MDI exposed population.

Objective: To establish a method for the determination of manganese in urine by graphite furnace atomic absorption spectrometry (AAS) without the use of matrix modifier. Methods: The urine samples were 5 times diluted with 1% nitric acid then directly determined by AAS. Zeeman was used for background correction. Results: The linear range for determination of manganese in urine was 5~60 μg/L (urine) . The correlation coefficient was greater than 0.995 with the detection limit of 1.5 μg/L and with the lower limit of quantification of 5.0 μg/L. The relative standard deviations (RSDs) of within-run precision was between 1.1%~4.3%, the RSDs of between-run precision was between 3.3%~7.0%. The average recovery was 102.6%. The samples can be stored for 14 days at room temperature, 4℃, -8 ℃ and -35 ℃. Conclusion The method is feasible for determination of manganese in urine.

Objective: To develop a method for Simultaneous and rapid determination of 12 rodenticides including pindone, vacor, coumatetralyl, warfarin, diphacinone, coumachlor, chlorphacinon, difenacoum, brodifacoum, bromadiolone, difethialone and flocoumafen in whole blood and urine samples by high performance liquid chromatography-tandem mass (LC-MS-MS) . Methods: The whole blood samples were precipitated with acetonitrile, purified by OstroTM 96-well plate, The urine samples were extracted by acetonitrile, and then separated on a ODS column, analyzed with high-performance liquid chromatography-tandem mass spectrometry (LC-MS/MS) . The external standard calibration were tested. Results: A good linearity was observed in their respective concentration ranges of 12 rodenticides. The related coefficients were 0.993 0~0.999 8. The limit of detections were 0.05 μg/L~1.4 μg/L. The rates of recovery were 92.5%~118.0%. The relative standard deviations were between 0.8%~17.3%. Conclusion The method was simple, rapid, sensitive, accurate and suitable for simultaneous detection of the 12 rodenticides in whole blood and urine samples of intoxicated patients.