1.Determination of trace oxalate and citrate in urine with capillary electrophoresis
Qiwen TAN ; Wei GUO ; Meixiu GU ; Chunyan ZHANG ; Baishen PAN
Chinese Journal of Laboratory Medicine 2014;37(4):281-284
Objective To establish a method for determining oxalate and citrate in urine simultaneously by capillary electrophoresis.The components,the concentration and pH of the buffer solution,the separation voltage and the injection time on theseparation were studied in detail.Methods The separations were carried out using potassium dihydrogen phosphatebuffer ina fused-silica capillary tubeby capillary zone electrophoresis (CZE) and the detection were monitored by UV.24 h-urine samples from patients (n =5) and health control (n =5) were collected from Zhongshan Hospital of Fudan University for systematically validating the method developed.Results The optimized separations were carried out using a 50 mmol/L potassium dihydrogen phosphatebuffer solution (pH 6.5) in a fused-silica capillary tube of 50 cm × 50 μm I.D.Injections were made by using the pressure mode for 10 s at 34 mbar.The detections were monitored by a UV at 200 nm after samples were separated at avohage of 30 kV.Under the seconditions,urinary oxalate and citrate were separated completely within 5 min.The relative standard deviations of migration time and peak area within-run foroxalate and citrate were less than 1% and 3.0% and the betweenrun relative standard deviations were less than 2.0% and 4.0%,respectively.The detection limits were 1 mg/L for both oxalate and citrate.The linearity ranges of oxalate and citrate were both 0-500 mg/L with the correlation coefficient between 0.999 5 and 0.995 4 (P < 0.05),respectively.The average recoveries were 102.38% for oxalate and 92.74% for citrate.Conclusion This method is proved to be simple,sensitive and accurate,and also applied to determine oxalate and citrate in urine samples with satisfactory results.
2.Rapid identification and correction of the interference of cold agglutinins by using RET channel red blood cell parameters
Wenjia TANG ; Shuo YANG ; Jie ZHU ; Hexi LI ; Meixiu GU ; Beili WANG ; Baishen PAN ; Wei GUO
Chinese Journal of Laboratory Medicine 2023;46(10):1020-1025
Objective:To assess the role of Delta-RBC parameters in the automated hematocrit analyzer RET channel for the recognition of cold agglutinins (CA) and to explore the value of RET channel optical method parameters in correcting interference with CA.Methods:This is a retrospective study. The Cas group included 68 samples with Cas interference and the control group included 45 samples without CA interference. All specimens were collected from Zhongshan Hospital Fudan University Outpatient Department from January 2022 to January 2023. Specimens in both the CA and Control group were examined using the CBC+RET channel at room temperature. Recorded and calculated the Impedance method test parameters RBC-I, HGB, HCT-I, MCH-I, MCV-I, MCHC-I and the Optical method test parameters RBC-O, HCT-O, MCH-O, R-MFV, MCHC-O, Delta-RBC. Examined the specimens in the CA group using the CBC channel after prewarmed at 37 ℃ for 2 h, and Impedance method parameters RBC-I 37 ℃ 2 h, HGB 37 ℃ 2 h, HCT-I 37 ℃ 2 h, MCH-I 37 ℃ 2 h, MCV-I 37 ℃ 2 h, MCHC-I 37 ℃ 2 h were recorded. The ROC curves were used to analyze the discrimination efficacy of Delta-RBC in identifying CA interference, and the Bland-Altman method was used to analyze the consistency between the results of the optical method RBC parameters at room temperature and the results of the impedance method after prewarming. The correlation analysis was performed using Pearson and Spearman correlation analysis to analyze the results of the RBC parameters before and after prewarming in the CA group. Result:If Delta-RBC was used as diagnostic indicators for the identification of CA interference, the best cut-off value was 1.065, with AUCs of 0.998. In the CA group, the correlation coefficients between RBC-O, HCT-O, R-MFV, MCH-O, MCHC-O, and RBC-I 37 ℃ 2 h, HCT-I 37 ℃ 2 h, MCV-I 37 ℃ 2 h, MCH-I 37 ℃ 2 h, MCHC-I 37 ℃ 2 h were 0.985, 0.981, 0.729, 0.870, and 0.649, respectively. The percentages within the limits of agreement of the percentage differences between the results of the two methods were 95.6%, 92.6%, 95.6%, 94.1%, and 95.6%, respectively. Conclusions:The RBC parameter Delta-RBC from RET channel optical method can be used as an indicator to effectively assist in the clinical determination of the presence of CA. Reporting results using the optical method RBC parameters of the RET channel can correct the interference of CA without specimen pre-treatment and obtain more correct results of complete blood counts.
3.Evaluation of clinical application of automatic coagulation detection assembly line in high-throughput specimen detection
Hui WU ; Lin SUN ; Meixiu GU ; Yichao GUO ; Chong WANG ; Beili WANG ; Baishen PAN ; Wei GUO
International Journal of Laboratory Medicine 2024;45(12):1416-1418,1424
Objective To evaluate the clinical application of automatic coagulation detection assembly line in high-throughput specimen detection.Methods The relevant information of sodium citrate anticoagulation samples in Zhongshan Hospital Affiliated to Fudan University from June to August 2021 was collected,inclu-ding sample collection time,receiving time,instrument sucking time,test completion time,and whether it pas-sed autoverification or not.The sample pretreatment time,testing time and turnaround time(TAT)of the au-tomatic coagulation detection assembly line were compared before and after installation,and the detection speed of the automatic coagulation detection assembly line was evaluated.Results The automatic coagulation detection line was expected to detect 650-900 samples per hour.The increase in the number of turbidimetric tests would slow down the detection speed of the instrument.Automatic coagulation detection assembly line test specimen to clinic and ward of pretreatment time and testing time were shorter than single detection,the differences were statistically significant(P<0.05).The automatic coagulation detection assembly line could shorten TAT(P<0.05).After the application of automatic coagulation detection assembly line,the autoveri-fication rate was 25.6%.Conclusion The automatic coagulation detection assembly line is suitable for high-throughput specimen detection in laboratory.Compared with stand-alone coagulation detection,the automatic coagulation detection assembly line could shorten TAT and testing time,and help to reduce the work pressure of laboratory personnel.