A Study of the Starch-Iodine Complex: A Modified Colorimetric Micro Determination of Amylase in Biologic Fluids

1964 ◽  
Vol 10 (10) ◽  
pp. 891-906 ◽  
Author(s):  
N R Pimstone
Keyword(s):  
Serum Amylase ◽  
Serum Proteins ◽  
Amylase Activity ◽  
Optimal Conditions ◽  
Serum Factor ◽  
Serum Factors ◽  
Iodine Complex ◽  
Human Sera ◽  
Initial Depression

Abstract The limitations, inaccuracies, and practical difficulties of saccharogenic methods are discussed. A modified colorimetric microdetermination of amylase is described in which the digestion of starch is measured by the decrease in the starch-iodine color. Experimental data show that there are two other serum factors that can also cause a fall-off in color: (1) an immediate 10-15% depression of color, probably due to serum proteins and countered by using serum in the control; (2) an acid-serum factor causing a progressive fall-off in color subsequent to the initial depression. Iodine prevents this, and must be added as soon as the acid has been added to stop the enzyme activity. Results of 189 consecutive assays of human sera are presented. Amylase activity of duodenal aspirate has been determined simultaneously by the method described and the Lagerlöf method. Results are compared. Changes in serum amylase and lipase levels in artificially produced pancreatitis in dogs are presented. Optimal conditions for amylase activity are reviewed, and in the light of these, different amyloclastic methods and their results compared. Achroic-point technics are briefly evaluated.

scholarly journals Secrets, puzzles and mysteries of macroamylasemia

2020 ◽  
Vol 46 (1) ◽  
pp. 12-22
Author(s):  
N. B. Gubergrits ◽  
N. V. Byelyayeva ◽  
G. M. Lukashevich ◽  
T. L. Mozhyna
Keyword(s):  
Serum Amylase ◽  
Amylase Activity ◽  
Clinical Manifestations ◽  
Specific Treatment ◽  
Normal Serum ◽  
Amylase Level ◽  
Clearance Ratio ◽  
Urine Amylase ◽  
Classical Constant

Physiological features of amylase synthesis and excretion are considered in the article, presence of other sources of amylase synthesis different from pancreas and salivary glands is emphasized. Definitions of hyperenzymemia and macroamylasemia (MAE) are given. MAE is a state characterized by presence of circulating complexes of normal serum amylase with protein or carbohydrates in blood. There are 3 types of MAE: first — classical (constant hyperamylasemia, decreased amylase level in urine, high blood concentration of macroamylase complexes); second — hyperamylasemia with slightly decreased amylase activity in urine, macroamylase/normal amylase ratio is less than in the first type; third — normal blood and urine amylase activity, low macroamylase/normal amylase ratio. Pathogenesis is explained by connection of blood amylase and acute phase protein in different inflammatory, infectious diseases, malabsorption. MAE clinical manifestations could be absent, sometimes abdominal pain is possible. Hyperamylasemia and reduced urine amylase activity are typical. MAE diagnostics means determination of macroamylase complexes in blood (chromatography, calculation of the clearance ratio of amylase and creatinine). The article presents clinical cases describing extra-pancreatic MAE in women with malignant ovarian lesions. The question of expediency of thorough diagnostic examination in asymptomatic MAE is raised, which may turn out to be a symptom of cancer. The lack of specific treatment for MAE is emphasized.

An Automated, Saccharogenic Method for Determining Serum Amylase Activity

1970 ◽  
Vol 16 (12) ◽  
pp. 985-989 ◽  
Author(s):  
Wendell R O'Neal ◽  
Nathan Gochman
Keyword(s):  
Glucose Oxidase ◽  
Blood Donors ◽  
Serum Amylase ◽  
Amylase Activity ◽  
Serum Glucose ◽  
Normal Range ◽  
Reducing Substances ◽  
Serum Amylase Activity

Abstract An automated adaptation of the Somogyi saccharogenic determination of serum amylase is described in which conventional AutoAnalyzer modules are used. Adequate sensitivity with short incubation is achieved by incorporating glucose oxidase and catalase in the substrate to destroy serum glucose during incubation. Maltose and other dialyzable oligosaccharides are measured with the alkaline copper-neocuproine reaction. A simultaneous blank run is performed to determine reducing substances other than glucose in serum. Precision studies and correlation with a manual saccharogenic method are presented. The normal range was determined from data for 49 healthy blood donors.

Determination of alpha-amylase activity: methods comparison and commutability study of several control materials

1995 ◽  
Vol 41 (3) ◽  
pp. 435-438 ◽  
Author(s):  
G Gubern ◽  
F Canalias ◽  
F J Gella
Keyword(s):  
Human Serum ◽  
Amylase Activity ◽  
Alpha Amylase ◽  
Human Origin ◽  
Serum Samples ◽  
Chromophore Group ◽  
Laboratory Control ◽  
Wide Range ◽  
Human Sera

Abstract Six different methods for alpha-amylase determination were compared by assaying human serum samples covering a wide range of alpha-amylase values. All the methods studied use as substrate a maltooligosaccharide with a chromophore group at the reducing end; some are chemically blocked at the nonreducing end. Intermethod comparison by regression and correspondence analyses showed significant differences for two methods. The commutability of 12 commercial control materials containing alpha-amylase was also assessed by the different methods in comparison with human serum specimens containing the pancreatic and salivary isoenzymes. We also studied the behavior of pancreatic and salivary materials prepared in our laboratory. Control materials with alpha-amylase of non-human origin were not commutable with the enzyme in human sera and should not be used for intermethod calibration.

Determination of amylase activity in serum by using a wheat germ inhibitor with the Du Pont aca.

1986 ◽  
Vol 32 (8) ◽  
pp. 1539-1541 ◽  
Author(s):  
D A Lacher ◽  
M B Harize
Keyword(s):  
Acute Pancreatitis ◽  
Wheat Germ ◽  
Serum Amylase ◽  
Amylase Activity ◽  
Reference Interval ◽  
Pancreatic Amylase ◽  
Wheat Germ Extract ◽  
Rapid Procedure ◽  
Assay Conditions

Abstract A rapid procedure for determining salivary- and pancreatic-type amylase (EC 3.2.1.1) in serum by incorporating a wheat germ inhibitor (from Triticum aestivum) was developed for the Du Pont aca IV analyzer. Under optimal assay conditions, activities of salivary and pancreatic amylase were inhibited by 93% and 19%, respectively. The 95% central reference interval for the percentage of inhibition of serum amylase was 38-84%. Patients with acute pancreatitis showed less than 26% inhibition of amylase after addition of the wheat germ extract, reflecting the prevalence of pancreatic-type amylase in this disorder.

Automated homogeneous liposome-based assay system for total complement activity

1995 ◽  
Vol 41 (4) ◽  
pp. 586-590 ◽  
Author(s):  
S Yamamoto ◽  
K Kubotsu ◽  
M Kida ◽  
K Kondo ◽  
S Matsuura ◽  
...  
Keyword(s):  
Serum Proteins ◽  
M Protein ◽  
Homogeneous Population ◽  
Complement Activity ◽  
Activity Test ◽  
Human Sera ◽  
Total Complement ◽  
Hemolytic Complement Activity ◽  
Glucose 6 Phosphate Dehydrogenase

Abstract We developed an automated homogeneous immunoassay, based on immune lysis of dinitrophenyl (DNP)-labeled liposomes, for measuring total complement activity. Liposome lysis caused by complement activity was detected spectrophotometrically from entrapped glucose-6-phosphate dehydrogenase activity. Complement activity in human sera was quantified by comparison with a calibration curve. For ease of application to fully automated routine clinical analyzers, we adopted a two-reagent system, one reagent containing a homogeneous population of small DNP-labeled liposomes and one containing antibody/substrate. This system required calibration only once a week. Within-run and between-run CVs were 0.4-1.3% (n = 10) and 1.8-4.7% (n = 10), respectively. Serum results were linear upon dilution (with saline) over a twofold range. Bilirubin, hemoglobin, Intrafat, and serum proteins such as rheumatoid factor, M protein, IgG, and IgA did not affect the assay results. The results (y) correlated well with those from a hemolytic complement activity test (x): y = 1.05x - 1.14, r = 0.92, on 66 samples in the range < 10- > 50 kU/L. This method should therefore be of great use for the determination of complement activity.

New Amylase Substrate and Assay Procedure

1970 ◽  
Vol 16 (1) ◽  
pp. 39-43 ◽  
Author(s):  
Arthur L Babson ◽  
Susan A Tenney ◽  
Robert E Megraw
Keyword(s):  
Linear Function ◽  
Tannic Acid ◽  
Alkaline Solution ◽  
Serum Amylase ◽  
Serum Proteins ◽  
Amylase Activity ◽  
Gel Filtration ◽  
Assay Procedure ◽  
Supernatant Solution

Abstract This report describes a new procedure for serum amylase assay. A novel substrate, dyed amylopectin, is used that combines the advantages of saccharogenic and amyloclastic methods. Serum amylase hydrolyzes the dyed amylopectin into ethanol-soluble fragments, which are quantified colorimetrically after serum proteins and unhydrolyzed substrate are precipitated with alcoholic tannic acid. The substrate is prepared by coupling Reactone Red 2B to amylopectin in alkaline solution. Unreacted dye is removed by gel filtration. The clear red solution of dyed amylopectin is buffered and diluted to a standard concentration; it can be preserved indefinitely by lyophilization. The assay procedure is the following: 0.2 ml serum is added to 1 ml substrate at 37°C. After incubation for 10 min, 5 ml of alcoholic tannic acid are added, and the mixture is centrifuged. Absorbance of the supernatant solution at 540 nm is a linear function of amylase activity. Serum blanks are not required. The results correlate well with the saccharogenic assay of Somogyi.

Characterization and intermethod relationships of materials containing purified human pancreatic and salivary amylase.

1981 ◽  
Vol 27 (5) ◽  
pp. 714-720 ◽  
Author(s):  
E J Sampson ◽  
P H Duncan ◽  
D M Fast ◽  
V S Whitner ◽  
S S McKneally ◽  
...  
Keyword(s):  
Serum Amylase ◽  
Amylase Activity ◽  
Human Albumin ◽  
Human Pancreas ◽  
Human Sera ◽  
Tris Hydrochloride ◽  
Liquid Pools ◽  
Characterization Of Materials ◽  
Salt Fractionation

Abstract We describe the preparation and characterization of materials containing human pancreatic and salivary alpha-amylase (EC 3.2.1.1) and examine their relationship to endogenous amylase in human serum. Amylase was purified from human pancreas and saliva by solvent- and salt-fractionation and column chromatography to specific activities of 63 and 279 kU/g, respectively. Four liquid pools, differing only in activity, were prepared from each source of amylase, each in a matrix containing, per liter: 30 g of human albumin, 50 mmol of sodium chloride, 1 mmol of calcium chloride, and 50 mmol of Tris hydrochloride buffer, pH 7.4. Characterization of the pools showed that the amylase activity in the materials was stable for at least six months at 25 degrees C; among-vial variability of amylase activity was less than or equal to 0.5% (2 CV); and the pools were free from eight possible contaminating enzymes. Plots of salivary vs pancreatic amylase activity measure in our materials with eight commercially available methods showed least-squares slopes ranging from 0.51 to 1.0. The intermethod "commutability" of the materials (i.e., how closely they mimic endogenous serum amylase) was examined in relationship to approximately 100 human sera.

Determination of pancreatic amylase activity by a radial diffusion assay

1970 ◽  
Vol 48 (11) ◽  
pp. 758-761 ◽  
Author(s):  
André Bélanger ◽  
Jean Perreault ◽  
Yvon Couture ◽  
Jacques Dunnigan
Keyword(s):  
Reaction Zone ◽  
Optical Density ◽  
Amylase Activity ◽  
Pancreatic Amylase ◽  
Insulin Hypoglycemia ◽  
Rat Pancreas ◽  
Iodine Complex ◽  
Radial Diffusion Assay ◽  
Diffusion Assay

A technique for assay of amylase content in homogenates of rat pancreas is described. It is based on the measurement of the diameter of a "reaction zone" resulting from the action of the enzyme diffusing through a gel containing the substrate. The method is used to evaluate the amylase content of the pancreas of rats stimulated by feeding and by insulin-hypoglycemia. The results are compared with those obtained by a classic amyloclastic method, using the optical density of the starch-iodine complex.

Three methods compared for determination of pancreatic and salivary amylase activity in serum of cystic fibrosis patients.

1986 ◽  
Vol 32 (2) ◽  
pp. 296-300 ◽  
Author(s):  
R O Wolf ◽  
V S Hubbard ◽  
B K Gillard ◽  
A Kingman
Keyword(s):  
Cystic Fibrosis ◽  
Gel Electrophoresis ◽  
Serum Amylase ◽  
Amylase Activity ◽  
Pancreatic Insufficiency ◽  
Polyacrylamide Gel Electrophoresis ◽  
Pancreatic Amylase ◽  
Salivary Amylase ◽  
Amylase Isoenzymes

Abstract We evaluated three methods for serum amylase (EC 3.2.1.1) isoenzymes to determine whether they are interchangeable and to test their ability to discriminate between cystic fibrosis patients with and without pancreatic insufficiency. One method involved salivary amylase inhibitor (O), and two were polyacrylamide gel electrophoresis separations differing in method of detection--either direct zymogram (G) or gel slicing followed by activity estimates per slice (W). Results for percentage pancreatic amylase differed significantly. Reproducibility for percentage pancreatic amylase was high, moderate, and low (r = 0.95, 0.53, and 0.02) for methods G, O, and W, respectively; moderate (r = 0.60) among the three methods; and moderate between pairs. Therefore, this result for a subject must be considered relative to the method used in its determination. The clinical diagnosis of pancreatic insufficiency was verified by 77.8%, 83.3%, and 94.4% correct classification rates for methods O, W, and G, respectively. Evidently, method G is the most efficient and may be the method of choice for measuring serum amylase isoenzymes in cystic fibrosis.

Kinetic Nephelometric Procedure for Measurement of Amylase Activity in Serum

1972 ◽  
Vol 18 (11) ◽  
pp. 1323-1325 ◽  
Author(s):  
James R Shipe ◽  
John Savory
Keyword(s):  
Standard Deviation ◽  
Light Scattering ◽  
Relative Standard Deviation ◽  
Serum Amylase ◽  
Amylase Activity ◽  
Stable Suspension ◽  
Relative Standard

Abstract We developed a kinetic procedure for determination of amylase activity in serum by use of nephelometric measurements. Light scattering from the substrate, a stable suspension of starch, is decreased as amylase hydrolyzes the starch to soluble fragments. Values obtained for serum amylase correlate closely with those determined by a method in which a starch-dye complex is used. Precision of the new procedure is 3.4% (relative standard deviation). Units of amylase activity can either be expressed in terms of milligrams of starch consumed or converted to more conventional amylase units.

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