Assessment of the benzethonium chloride method for routine determination of protein in cerebrospinal fluid and urine.

1983 ◽  
Vol 29 (2) ◽  
pp. 343-345 ◽  
Author(s):  
E Flachaire ◽  
O Damour ◽  
J Bienvenu ◽  
T Aouiti ◽  
R Later
Keyword(s):  
Cerebrospinal Fluid ◽  
Urinary Protein ◽  
Protein Determination ◽  
Benzethonium Chloride ◽  
Chloride Method

Abstract We have tested the characteristics of the method of Iwata and Nishikaze (Clin Chem 25: 1317, 1979). The linearity, sensitivity, and precision are satisfactory and the reactivity of benzethonium chloride with various proteins (albumin, immunoglobulins) is the same. The method has been compared with Meulemans's technique (Clin Chim Acta 5: 757, 1960), routinely used in our laboratories, by analysis of 82 samples of cerebrospinal fluid (CSF) and 119 samples of urine. Our results for cerebrospinal fluid agree well with those of Iwata and Nishikaze (r = 0.976; y = 0.992x - 0.013), but we find their method unsuitable for urinary protein determination, probably because of interfering compounds in urine.

A Fluorometric Ferric Chloride Method for Determining Cholesterol in Cerebrospinal Fluid and Serum

1970 ◽  
Vol 16 (6) ◽  
pp. 472-476 ◽  
Author(s):  
Elizabeth B Solow ◽  
L W Freeman
Keyword(s):  
Cerebrospinal Fluid ◽  
Ferric Chloride ◽  
Rapid Determination ◽  
Biological Fluids ◽  
The Past ◽  
Highly Sensitive ◽  
Chloride Method ◽  
Cholesterol Measurement

Abstract Sensitive or simple methods for the rapid determination of cholesterol in biological fluids have been developed during the past 10 years. Sensitivity has been increased by fluorimetry of the Lieberman—Burchard reaction for cholesterol. Measurement of the reaction of cholesterol with ferric chloride is simpler. Still, there are great differences between the results when different methods are used to measure the microquantities of cholesterol present in small volumes of serum or cerebrospinal fluid. In the proposed method, the simpler ferric chloride technique has been made highly sensitive by use of fluorometry. As little as 100 µl of cerebrospinal fluid, containing less than 1 µg of cholesterol, may be used, and the reaction is stable for as long as 1 h. Interference was negligible from pigments (such as bilirubin and hemoglobin), certain drugs, and ionic substances that might be expected to affect fluorescence.

New micro-turbidimetric method for determination of protein in cerebrospinal fluid and urine.

1979 ◽  
Vol 25 (7) ◽  
pp. 1317-1319 ◽  
Author(s):  
J Iwata ◽  
O Nishikaze
Keyword(s):  
Cerebrospinal Fluid ◽  
Gamma Globulin ◽  
Sulfosalicylic Acid ◽  
Trichloracetic Acid ◽  
Micro Scale ◽  
Turbidimetric Method ◽  
Classic Method ◽  
Benzethonium Chloride ◽  
Higher Sensitivity

Abstract We report a new micro-scale (0.1-mL sample) turbidimetric method for determination of protein by use of benzethonium chloride in alkali. The method is highly specific for protein, has a higher sensitivity than the classic method of Lowry et al., and shows satisfactory reproducibility and recovery. The turbidity produced in our method is the same for albumin and gamma-globulin and is more stable than in Meulemans' method (in which sulfosalicylic acid is used) or in the method of Bossak et al. (in which trichloracetic acid is used). In contrast to Pesce and Strande's method, there is no manipulative loss of protein.

scholarly journals Comparison of urine protein creatinine ratio and 24 hours urine protein in detecting preeclampsia

2019 ◽  
Vol 14 (2) ◽  
pp. 49-53
Author(s):  
Nesuma Sedhain ◽  
Jageshwor Gautam ◽  
Gehanath Baral
Keyword(s):  
Area Under The Curve ◽  
Urinary Protein ◽  
Creatinine Ratio ◽  
Urine Protein ◽  
Protein Determination ◽  
Cross Sectional ◽  
Spot Urine ◽  
Urine Protein Excretion ◽  
Protein Excretion

Aim: To assess the diagnostic accuracy of spot urine protein-creatinine ratio for detection of proteinuria in Preeclampsia. Methods: Cross Sectional Descriptive Study was conducted in a total of 38 pregnant women in Paropakar Maternity and Women’s Hospital in study period of 3 month. The correlation between protein- creatinine ratio in spot urine samples and urinary protein excretion in 24-hour collections were analyzed. Results: Comparison of 24 hours urinary protein and protein- creatinine ratio in women with preeclampsia shows a significant correlation (r=0.911, p<0.0001). The cut-off protein-creatinine ratios which gave maximum area under the curve for 300mg protein for 24hrs was 0.27 (sensitivity: 94.6%, specificity: 100%, PPV: 100%, NPV: 33.3%); 2000 mg urine protein excretion was 2.1 (sensitivity and specificity of 100%); 3000mg protein excreted for 24hours was 3.0 (sensitivity: 83.3%, specificity: 92.3%, PPV: 83.3%, NPV: 93.3%. Area under the ROC for 24hours urine total protein of >300mg, >2000mg and >3000mg/day were 0.946 (95%CI 0.873-1.019), 1 (95% CI 1.00-1.00) and 0.957 (95%CI 0.897- 1.016) respectively. Conclusions: Spot urine protein-creatinine ratio is as accurate as to 24 hours urine protein determination of proteinuria in Preeclampsia.

Six methods for determining urinary protein compared.

1983 ◽  
Vol 29 (3) ◽  
pp. 553-557 ◽  
Author(s):  
B A Dilena ◽  
L A Penberthy ◽  
C G Fraser
Keyword(s):  
Narrow Range ◽  
Urinary Protein ◽  
Urine Protein ◽  
Sulfosalicylic Acid ◽  
Protein Determination ◽  
Turbidimetric Method ◽  
Low Concentrations ◽  
Ponceau S ◽  
Coomassie Brilliant

Abstract Inter-laboratory surveys have shown that "routine methods" of urinary protein determination are often unsatisfactory. Therefore, we compared six frequently used methods for determination of protein in urine with respect to linearity, within-batch and between-batch precision, comparative bias, and practicability. We assayed dilutions of human and bovine albumin and serum, and fresh and lyophilized human urine. We find that the AACC Selected Method has poor practicability and poor precision under routine conditions, but good linearity. The sulfosalicylic acid/biuret technique is also impracticable, requires a large sample, and is not linear at low concentrations of urine protein. The Coomassie Brilliant Blue technique has a narrow range of linearity and poor precision. The sulfosalicylic acid/sodium sulfate turbidimetric method is not precise and cannot be standardized with bovine materials. The Ponceau-S technique has good performance characteristics and practicability, and we recommend it for routine laboratory use.

Nephelometric Determination of Total Protein in Cerebrospinal Fluid and Urine Using Benzalkonium Chloride as Precipitation Reagent

1992 ◽  
Vol 29 (4) ◽  
pp. 411-417 ◽  
Author(s):  
Mark D S Shephard ◽  
Malcolm J Whiting
Keyword(s):  
Cerebrospinal Fluid ◽  
Total Protein ◽  
Benzalkonium Chloride ◽  
Trichloroacetic Acid ◽  
Urine Samples ◽  
Good Precision ◽  
Benzethonium Chloride ◽  
Ponceau S ◽  
Sulphosalicylic Acid

Four different protein precipitants, namely trichloroacetic acid, sulphosalicylic acid, benzethonium chloride and benzalkonium chloride, were used to estimate the total protein concentration in cerebrospinal fluid and urine by nephelometry. Protein determinations for 50 cerebrospinal fluid samples and 100 urine samples were compared with values obtained by a trichloroacetic acid-Ponceau S spectrophotometric method. All methods were correlated well, but total protein results using acid precipitants were usually lower, while results obtained using benzethonium chloride were generally higher, than results obtained by the trichloroacetic acid-Ponceau S method. Anomalous results were obtained for some urine samples with benzethonium chloride, but not with benzalkonium chloride. Assays using benzalkonium chloride as precipitating reagent showed good precision and closest agreement with the trichloroacetic acid-Ponceau S dye-binding method. The use of benzalkonium chloride as precipitant is recommended for automated cerebrospinal fluid and urine protein estimations by nephelometry.

Determination of Melatonin Hormone and Neurotransmitters in Cerebrospinal Fluid: Method Validation and Uncertainty Calculations

2018 ◽  
Vol 73 (6) ◽  
pp. 613-625
Author(s):  
Özge Yetgin Çetin ◽  
Hatice Karadeniz ◽  
Alper Karakaş ◽  
Serpil Yenisoy-Karakaş
Keyword(s):  
Cerebrospinal Fluid ◽  
Method Validation

Resistance to Outflow of Cerebrospinal Fluid Determined by Bolus Injection Technique and Constant Rate Steady State Infusion in Humans

Neurosurgery ◽  
1985 ◽  
Vol 16 (3) ◽  
pp. 336-340 ◽  
Author(s):  
Michael Kosteljanetz
Keyword(s):  
Cerebrospinal Fluid ◽  
Steady State ◽  
Bolus Injection ◽  
Point Of View ◽  
Injection Technique ◽  
Communicating Hydrocephalus ◽  
Constant Rate ◽  
High Degree ◽  
Infusion Technique

Abstract Two methods for the determination of resistance to the outflow of cerebrospinal fluid, the bolus injection technique and the constant rate steady state infusion technique, were compared. Thirty-two patients with a variety of intracranial diseases (usually communicating hydrocephalus) were studied. There was a high degree of correlation between the resistance values obtained with the two methods, but values based on the bolus injection technique were systematically and statistically significantly lower than those obtained with the constant rate infusion test. From a practical point of view. both methods were found to be applicable in a clinical setting.

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