Isopropylidine maltoheptosyl fructofuranoside, doubly blocked substrate for determination of endoamylase activity

1991 ◽  
Vol 37 (8) ◽  
pp. 1323-1328
Author(s):  
Z Ogawa ◽  
Y Matsubayashi ◽  
S Satoh ◽  
N Orita ◽  
H Itoh
Keyword(s):  
Human Serum ◽  
Coefficient Of Variation ◽  
Oxidation Rate ◽  
Amylase Activity ◽  
Mannitol Dehydrogenase ◽  
Coupled Reactions ◽  
Alpha Glucosidase ◽  
Serum And Urine

Abstract We synthesized o-(4,6-o-isopropylidene-alpha-D-glucopyranosyl)-(1----4)- [o-alpha-D-glucopyranosyl-(1----4])5-o-alpha-D-glucopyranosyl-(1----2)- alpha-D-fructofuranoside (IPG7F) and developed an assay for determining the activity of amylase in human serum and urine by using this substrate. Glucoamylase, alpha-glucosidase, and mannitol dehydrogenase are used as coupling enzymes. The coupled reactions are monitored by continuously measuring the oxidation rate of NADH. In this procedure, various substances in the test specimens do not interfere with the detection of amylase activity. Exactly one molecule of NADH is oxidized by one attack of amylase on the substrate, although four products can be produced in the reaction. The within-assay coefficient of variation (CV) ranged from 1.0% to 4.1% and the between-assay CV ranged from 2.6% to 5.3%. The results of our new assay correlate well with those of the amylase assay involving p-nitrophenol maltoheptaoside as substrate (r = 0.978) and with those of the amylase assay involving maltopentaose (r = 0.987).

New saccharogenic determination of alpha-amylase in serum and urine.

1979 ◽  
Vol 25 (2) ◽  
pp. 215-217 ◽  
Author(s):  
L van Leeuwen
Keyword(s):  
Human Serum ◽  
Amylase Activity ◽  
Glucose Dehydrogenase ◽  
Alpha Amylase ◽  
Endogenous Glucose ◽  
Alpha Glucosidase ◽  
Serum And Urine

Abstract I describe a new kinetic enzymatic saccharogenic method for assaying alpha-amylase in human serum and urine. alpha-Amylase liberates maltose from starch. This is successively acted on by alpha-glucosidase, mutarotase, and glucose dehydrogenase. The resulting conversion of NAD+ to NADH, measured at 340 nm, during a 20-min incubation reflects amylase activity. Endogenous glucose is destroyed before measurement of amylase activity is begun.

Electrophoretic pattern of amylase isoenzymes in serum and urine of normal persons.

1976 ◽  
Vol 22 (4) ◽  
pp. 439-444 ◽  
Author(s):  
M Otsuki ◽  
S Saeki ◽  
H Yuu ◽  
M Maeda ◽  
S Baba
Keyword(s):  
Thin Layer ◽  
Human Serum ◽  
Salivary Glands ◽  
Clinical Medicine ◽  
Amylase Activity ◽  
Electrophoretic Pattern ◽  
Normal Pattern ◽  
Amylase Isoenzymes ◽  
Serum And Urine

Abstract We separated and measured amylase isoenzymes in the serum and urine of 3036 normal persons by electrophoresis on a thin layer of polyacrylamide gel. We wished to establish the normal pattern of these isoenzymes and to evaluate the usefulness of this method of electrophoresis in clinical diagnosis. Results for patients with hyper- or hypofunctioning pancreas and salivary glands suggested that essentially all the isoamylases in human serum and urine are derived from the salivary glands and the pancreas, and revealed that isoamylases of more than 98% of normal persons consisted of two major isoenzymes and two to three minor ones. Although these observations indicate that data on changes in the proportion of amylase activity of each isoenzyme can be useful in clinical medicine, the following points should be remembered: (a) quantitative differences in the isoenzyme pattern were observed, depending upon the condition of the samples; (b) because the proportion of isoamylase activity in serum of different normal persons differs, seriatim determination of amylase isoenzymes is necessary; and (c) because five different genetically controlled types of isoamylases were observed in normal persons, genetic investigations are also necessary.

A highly selective colorimetric assay for the determination of creatinine in biological samples using gluconic acid capped silver nanoparticles after ionic liquid based dispersive liquid phase microextraction

2021 ◽  
pp. 1-8
Author(s):  
Susan Sadeghi ◽  
Mohadeseh Hosseinpour-Zaryabi
Keyword(s):  
Silver Nanoparticles ◽  
Ionic Liquid ◽  
Liquid Phase ◽  
Human Serum ◽  
Gluconic Acid ◽  
Ag Nps ◽  
Liquid Phase Microextraction ◽  
Relative Standard ◽  
Serum And Urine

A dispersive liquid-phase microextraction method combined with UV–vis spectrophotometry was utilized to highly selective determination of creatinine in human serum and urine samples. To overcome the interferences in complex matrices, creatinine reacted with 1,4-naphthoquinone-2- potassium sulfonate reagent to produce a red coloured product that could be extracted into a small volume of 1-hexyl-3-methylimidazolium hexafluorophosphate ([HMIM]PF6) ionic liquid solvent. To increase the sensitivity of the assay, gluconic acid capped silver nanoparticles (Ag NPs) were used. On addition of Ag NPs to the red coloured extracted product, the solution turned to blue accompanied with a red shift in wavelength around 620 nm that could be detected by the naked eye. The effective variables on the determination of creatinine such as concentration of the reagent, amount of formic and hydrochloric acids, type and volume of the extractant, and concentration of Ag NPs were investigated. Under the optimal conditions, the calibration plot was bimodal with linear ranges from 0.1 to 1.5 µg mL−1 and 1.5 to 105 µg mL−1 creatinine with a limit of detection 0.1 µg mL−1. The relative standard deviation for five measurements at 35 µg mL−1 concentration level was 3.8%. The newly developed assay was used for the determination of creatinine in human serum and urine specimens with satisfactory results.

Enzyme-coupled ultraviolet determination of alpha-amylase activity with the GEMSAEC centrifugal analyzer.

1978 ◽  
Vol 24 (9) ◽  
pp. 1620-1624 ◽  
Author(s):  
W H Porter ◽  
R E Roberts
Keyword(s):  
Linear Response ◽  
Amylase Activity ◽  
Kinetic Studies ◽  
Alpha Amylase ◽  
Coefficients Of Variation ◽  
Endogenous Glucose ◽  
Glucose 6 Phosphate Dehydrogenase ◽  
Alpha Glucosidase ◽  
As Effects

Abstract We evaluated the Harleco alpha-glucosidase/hexokinase/glucose-6-phosphate dehydrogenase-coupled alpha-amylase method, bu use of the GEMSAEC centrifugal analyzer. Performance evaluation included kinetic studies of substrate and maltose hydrolysis as well as effects of endogenous glucose and fructose. The reagent was found to give a linear response with alpha-amylase activity to greater than 1200 U/liter. Within-run precision resulted in coefficients of variation (CV) of 0.9 to 3.2% over the range studied. Day-to-day precision corresponded to CV's of 2.4 to 4.4% over the same range of alpha-amylase procedure was found to be good (r = 0.997) for patients' sera examined.

scholarly journals Determination of Picogram Levels of Roxithromycin in Pharmaceutical, Human Serum, and Urine by Flow-Injection Chemiluminescence

2012 ◽  
Vol 2012 ◽  
pp. 1-5
Author(s):  
Jiangman Liu ◽  
Huan Yang ◽  
Yun Zhang ◽  
Min Wu ◽  
Haixiang Zhao ◽  
...  
Keyword(s):  
Human Serum ◽  
Flow Injection ◽  
Limit Of Detection ◽  
Inhibitory Effect ◽  
Injection System ◽  
Relative Standard ◽  
Flow Injection System ◽  
Flow Injection Chemiluminescence ◽  
Serum And Urine

A sensitive chemiluminescence (CL) method, based on the inhibitory effect of roxithromycin (ROX) on the CL reaction between luminol and dissolved oxygen in a flow-injection system, was first proposed for the determination of ROX at picogram levels. The decrement of CL intensity was linearly proportional to the logarithm of ROX concentrations ranging from 0.1 to 100 pg mL-1, giving the limit of detection (LOD) of 0.03 pg mL-1 (3σ). At a flow rate of 2.0 mL min-1, a complete analytical procedure including sampling and washing could be performed within 0.5 min, with relative standard deviations (RSDs) of less than 5.0% (n=5). The proposed procedure was applied successfully to the determination of ROX in pharmaceutical, human serum, and urine with the recoveries ranging from 90.0 to 110.0%.

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