BACKGROUND: The amount of interference due to hemolysis, bilirubin, and lipemia can be measured on the AU5800 autoanalyzer (Beckman Coulter, USA) by spectrophotometry. This is reported as semi-quantitative indices, specifically H-index, I-index, and L-index, respectively. In this study, we evaluated the impact of interference using chemistry assays and established the concentration of interfering substances and HIL-index above which analytically significant interference exists, according to CLSI guidelines C56-A and EP7-A2. METHODS: Pooled sera including different concentrations of analytes were prepared and mixed with hemoglobin, bilirubin, or Intralipid. These samples were then tested for 35 clinical chemistry analytes by AU5800 and the bias based on interferent concentrations was computed. The interferent concentration above which significant interference exists was calculated from the 50% within-subject biological variation (desirable analytic goal), and the corresponding index was assigned. RESULTS: Among 35 items evaluated, interference was detected for 12 analytes by hemoglobin, 7 analytes by bilirubin, and 12 analytes by Intralipid. We proposed HIL-index₁ and HIL-index₂ for each analyte according to 2 different medical decision levels. HIL-index₁ and HIL-index₂ were considered more reasonable criteria than the HIL-index from the manufacturer's technical document (HIL-index(TD)). This is because HIL-index(TD) was empirically set to 5% or 10%, and had a wide tolerance range, which was not sufficient to reflect the presence of interference, compared to HIL-index₁ and HIL-index₂. CONCLUSIONS: We have demonstrated hemoglobin, bilirubin, and Intralipid interferences according to CLSI guidelines using the desirable analytic goal. Our results provide applicable information for Beckman Coulter automated chemistry analyzers.
Bias (Epidemiology) ; Bilirubin ; Chemistry ; Chemistry, Clinical ; Hemolysis* ; Hyperlipidemias* ; Jaundice* ; Spectrophotometry

BACKGROUND: Recently, a new automated chemistry analyzer, Atellica CH930 (Siemens, Germany), was introduced. It automatically measures internal quality control (QC) materials according to a pre-determined schedule. For this purpose, the instrument has space for storage of QC materials. We evaluated the analytical performance of chemistry items by using the Atellica system. METHODS: The precision of 29 items was evaluated with three levels of QC materials with two storage methods. We stored the QC materials in the dedicated storage space in the instrument during the precision evaluation period. In addition, we aliquoted and stored the materials in the refrigerator, and then loaded the material in a timely manner. Linearity, carry-over, and agreement with current methods were also evaluated. RESULTS: The within-laboratory coefficient of variation (CV) of most items, except for total CO2 (tCO2), was within 5.0% in both QC storage methods without significant differences in CV between storage methods. The CV of tCO2 was 5.2%, 5.8%, and 5.1% at three different levels when the QC materials were stored in a dedicated space in the instrument. The linearity was acceptable, showing <5% nonlinearity. Although good agreement was observed for most items, some items, such as calcium, total bilirubin, aspartate transaminase, and chloride, showed unequivalent results. CONCLUSIONS: Atellica CH930 showed acceptable precision, linearity, and agreement in routine chemistry items. The automatic QC function using the storage device has no problem with stability or precision. It can reduce the manual process, allowing technicians to focus on reviewing the QC results and reporting reliable results.
Appointments and Schedules ; Aspartate Aminotransferases ; Bilirubin ; Calcium ; Chemistry ; Quality Control

Polystyrene microspheres (PS) were successfully prepared by suspension polymerization processes. Chloroacetylated polystyrene has been prepared by Friedel-Crafts acetylation of PS with chloroacetyl chloride. In this report, carcinogenic compound (chloromethylether etc.) was avoided. The effects of solvent, catalyst, acylating agent and reaction time were studied. Novel adsorption resins were obtained by synthesis of chloroacetylated polystyrene with amine. The influences of solvent, amine reagent and reaction time on ion exchange capacity were investigated. Under the optimized reaction condition, the ion exchange capacity of the prepared resins was 4.1587 mmol/g. The maximum amount of adsorbed bilirubin was 30.85 mg/g, the adsorption percentage was 80%.
Acetates ; chemistry ; Adsorption ; Amines ; chemistry ; Bilirubin ; chemistry ; Humans ; Microspheres ; Polystyrenes ; chemical synthesis ; Porosity ; Resins, Synthetic ; chemical synthesis ; chemistry

BACKGROUND: JEOL BioMajesty JCA-BM6010/C (JCA-BM6010/C, JEOL Ltd., Japan) is a recently developed ultra-compact automated clinical chemistry analyzer with a throughput of 1,200 tests per hour. Here, we present the first performance evaluation of JCA-BM6010/C. METHODS: We evaluated the precision, linearity, correlation, accuracy, and carryover of 11 analytes (ALP, ALT, AST, calcium, creatinine, GGT, glucose, LDH, total bilirubin, total protein, and uric acid) using the JEOL closed reagent (JEOL Ltd.) according to the guidelines of the Clinical Laboratory Standards Institute. Linearity was further evaluated for ALT, AST, and GGT using open reagents by Sekisui (Japan). The performance of JCA-BM6010/C was compared to that of the Roche-Hitachi Cobas 8000 c702 chemistry autoanalyzer (Cobas 8000, Roche Diagnostics, Switzerland). Its performance using open reagents from Denka Seiken (Japan), Roche, and Sekisui was also evaluated. RESULTS: The total coefficients of variation (CV) for all analytes were 1.0–2.7%. Linearity was observed for all analytes over the entire tested analytical range (R²≥0.99). The results of JCA-BM6010/C strongly correlated (r≥0.988) with those of Cobas 8000 for all evaluated analytes except LDH (r=0.963), as well as for all open reagents. Recovery rates for creatinine, glucose, calcium, and uric acid were 96.6–101.5% and 98.7–109.3% with the JEOL exclusive and open reagents, respectively. Sample carryover was less than 0.34%. CONCLUSIONS: JCA-BM6010/C showed acceptable performance in the precision, linearity, correlation, accuracy, and sample carryover analyses and in the method comparison. Therefore, it could be a useful routine laboratory medical analyzer.
Bilirubin ; Calcium ; Chemistry ; Chemistry, Clinical* ; Creatinine ; Glucose ; Indicators and Reagents ; Methods ; Uric Acid

BACKGROUND/AIMS: Our previous studies of ionization and solubility of unconjugated bilirubin (UCB) yielded inappropriately large differences between the two carboxylic pK'a values of UCB. These data, however, were not ideal due to crystal effects, matastability, impurities of the bilirubin, and imprecision of analyses at low UCB. METHODS: The sodium salt of taurocholate (TC) was purified and dissolved in water to 100 mM. Chloroform (CHCl3) was purified by vacuum distillation. Buffers used were: citrate from pH 4 to 6, phosphate from pH 6 to 8, and borate above pH 8. All had an ionic strength of 0.10. The problems were minimized by rapid solvent partition of UCB from CHCl3 into buffered aqueous NaCl, and a new, accurate assay of low UCB in the aqueous phase which was achieved by concentrating the UCB through back extraction into small volumes of CHCl3. RESULTS: In contrast with the crystal dissolution studies, the two pK'a value were similar. H2B0, not HB-, was the dominant UCB species in the pH range of bile (6.0 to 8.0). The aqueous solubilities of UCB were 90 to 98% less. Less than 0.01% of the bile salt partitioned into the CHCl3 phase and self-association of B= was negligible. UCB solubilities in 50 mM TC were 2 to 10% of those obtained by crystal dissolution, and, up to pH 7.9, were below the maximum UCB concentration in normal human bile. CONCLUSIONS: We suggest that the markedly increased binding of UCB with each ionization step is due to the disruption of the internal hydrogen bonds of the ionized carboxyl groups on interaction with the bile salt. We propose to extend the study of partition to determine the activity and the degradation products of calcium salts of unbound bilirubin fractions.
Bilirubin/*chemistry ; Chloroform ; English Abstract ; Hydrogen-Ion Concentration ; In Vitro ; Solubility ; Solvents ; Taurocholic Acid/*chemistry

BACKGROUND: Results of automated clinical chemistry tests are affected by many factors including analytical variability. In 1976, the College of American Pathologists (CAP) Conference on the analytical goals in clinical chemistry recommended that analytical variability should be less than 1/4 of the appropriate biological variability to improve distinction between normal and diseased populations. This study is conducted to evaluate whether automated clinical chemisty analyses performed in our laboratory is in conformance with the CAP's recommendation. METHODS: Routine chemistry and electrolyte tests were performed using Hitachi 747 automatic analyzer on 22 healthy volunteers. Blood samples were obtained from the volunteers' same vein twice in one week interval to study the total variability. Serum samples from 12 subjects were tested in duplicate immediately after blood collection for within-run analytical variability; and samples from another 10 subjects were repeated after 6 hours for within-day analytical variability. Within-run analytical variability plus within-day analytical variability make total analytical variability. Biological variability was defined as the difference between total variability and the analytical variability. Finally, ratios of analytical and biological variabilities were calculated. RESULTS: The ratios of analytical and biological variabilities of uric acid, glucose, and K were less than 0.25. But ratios of BUN, PO4, alkaline phosphatase, total bilirubin, AST, cholesterol, ALT, Cl, and protein exceeded 0.25. The ratios of Na, Ca, albumin, CO2, and creatinine could not be calculated. CONCLUSIONS: It is suggested that the analytical processes of the automated clinical chemistry tests be improved so as to be in conformity with the CAP's recommendation.
Alkaline Phosphatase ; Bilirubin ; Chemistry ; Chemistry, Clinical* ; Cholesterol ; Clinical Chemistry Tests* ; Creatinine ; Glucose ; Healthy Volunteers ; Uric Acid ; Veins

Six trials with 3 samples for each of external quality assessment for general chemistry and blood gas were performed in 2007. All the control materials were sent in specifically-made boxes at the same time. The response rates were 92.0% in general chemistry and 95.5% in blood gas. The items included sodium, potassium, chloride, BUN, glucose, calcium, phosphorus, uric acid, creatinine, bilirubin, total protein, albumin, total cholesterol, triglyceride, AST, ALT, ALP, LD and GGT in general chemistry and pH, pCO2 and pO2 in blood gas. Compared with the previous year (2006), the methods of analysis were slightly changed and the coefficient of variation and VIS scores of general chemistry items were not significantly changed.
Bilirubin ; Calcium ; Chemistry, Clinical ; Cholesterol ; Creatinine ; Glucose ; Hydrogen-Ion Concentration ; Korea ; Phosphorus ; Potassium ; Sodium ; Uric Acid

BACKGROUND: Many reagents have been developed along with advances in chemistry auto analyzer. Deciding on an appropriate reagent is required for an accurate test, diagnosis and efficient laboratory management. We evaluated Cica Liquid reagent produced by Kanto chemical corporation (Tokyo, Japan) for checking reagent ability. METHODS: Twelve chemistry reagents (AST, ALT, ALP, glucose, BUN, creatinine, total bilirubin, direct bilirubin, cholesterol, triglyceride, iron, magnesium) were tested on precision, linearity, interference, and correlation. We have evaluated using Hitachi 7600 (Hitachi High Technologies co., Japan) chemistry auto analyzer in accordance with the CLSI guidelines EP5-A, EP6-A, EP7-A, EP9-A2. EP_Suite (Marchem Associates Inc., USA) and SPSS ver. 11.0 (SPSS Inc., USA) were used for statistics. RESULTS: Precision results were satisfactory to CLIA '88 in all of the analytes except for ALP and magnesium. The linearity was satisfactory in measurement ranges as all analytes showed linearity in polynomial regression result or relative nonlinearity of less than 2.5%. Coefficients of correlation were above 0.985 in all analytes except for direct bilirubin and magnesium. When interference test results were compared with criteria of CLIA '88, low level of AST was positively interfered by hemoglobin and magnesium was negatively interfered by bilirubin. CONCLUSIONS: In conclusion, the Kanto Cica Liquid reagents are valuable in clinical laboratory, since they showed good precision, linearity, and correlation with other reagents.
Bilirubin ; Chemistry* ; Cholesterol ; Creatinine ; Diagnosis ; Glucose ; Indicators and Reagents* ; Iron ; Magnesium ; Triglycerides

BACKGROUND: The Rx Imola (Randox, UK) is newly released bench top - fully automated analyzer based on Window XP software with high-throughput (640 tests per hour with ISE) and continuous random access. We evaluated the performance of Rx Imola for the routine chemistry. METHODS: Repeatability (within-day precision), between-day precision, within-device precision, linearity, recovery rates and correlation were evaluated for 19 items including AST, ALT, ALP, GGT, total bilirubin, calcium, phosphorus, albumin, total protein, BUN, creatinine, glucose, amylase, total cholesterol, triglyceride, HDL, LDH, CK and uric acid. Commercialized quality control materials and patient's sera were used. For correlation study, 747-100 (HITACHI, Japan) and VITROS 950 (Ortho-Clinical Diagnostics, USA) were used as comparative analyzers. RESULTS: Coefficients of variation (CVs) of all items in repeatability and between-day precision study were below 5%. The linearities were statistically acceptable (R2>0.99) for all items. The recovery rates ranged from 95.7 to 105.3%. The comparison study showed high correlation between Rx Imola and 747-100 or VITROS 950. Correlation coefficients of all items were above 0.99 except HDL and albumin. CONCLUSIONS: This study showed satisfactory results in precision, linearity, recovery rates and comparison studies of Rx Imola. It was expected to be useful for routine chemistry analysis and back up, because of high performance, easy handling and small size.
Amylases ; Bilirubin ; Calcium ; Chemistry* ; Cholesterol ; Creatinine ; Glucose ; Phosphorus ; Quality Control ; Statistics as Topic ; Triglycerides ; Uric Acid

BACKGROUND: Hitachi 7600-110 (Hitachi, Tokyo, Japan) is an automated chemistry analyzer introduced in 1999. It consists of one dispensing type plus one pipetting type module and one electrolyte analyzer. We evaluated the performance of the analyzer in order to access the utility of the Hitachi 7600-110 autoanalyzer for the efficiency of routine chemistry work. METHODS: Within-day and between-day precision, accuracy, linearity, and recovery rates for albumin, ALP, ALT, AST, BUN, Ca, cholesterol, creatinine, r-GT, glucose, phosphorus, total bilirubin, TG, total protein, uric acid, CK, direct bilirubin, Fe, HDL-cholesterol, LD, Mg, Cl, K, and Na (24 items) were evaluated. Commercialized quality control material, Lyphochek (Bio-Rad, CA, USA) and patient sera for test specimens were used. Vitros 750 (Johnson & Johnson, Rochester, USA) was used as a control analyzer to evaluate the correlation. RESULTS: The within-day coefficients of variations (CVs) of almost all items were less than 3.0% except for direct bilirubin (7.71%), Mg (6.65%), and Fe (5.83%). The between-day CVs of almost all items were less than 5% except the direct bilirubin (13.16%). All items showed good linearity in the performance range (r>0.99, slope, 0.97-1.0). The results of ALT, AST, BUN, creatinine, glucose, CK, LD, Cl, K, and Na between Hitachi 7600-110 and the Vitros 750 revealed good correlation (r> or = 0.975) except Na and Cl. Hitachi data of Na and Cl showed significantly lower results (P<0.05) than did the Vitros 750 data. The recovery rates for BUN, creatinine, glucose, and uric acid were in the range of 100.00 to 101.78%. CONCLUSIONS: Hitachi 7600-110 showed acceptable performance in the "within-day" and "between-day" precision, linearity, and accuracy. The Hitachi 7600-110 that combines dispensing and pipetting modules can improve the speed and the efficiency of the workflow and can minimize the reagent consumption and the cost of system management. Therefore, it can be used both in large laboratories in general hospitals with many examinations and in small laboratories with relatively small numbers of cases.
Bilirubin ; Chemistry* ; Cholesterol ; Creatinine ; Glucose ; Hospitals, General ; Humans ; Phosphorus ; Quality Control ; Uric Acid