2.1.6 Carbohydrates (Chemical Methods) Flashcards
In copper reduction, what is the common initial reaction for it?
a. Beer’s reaction
b. Copper reaction
c. Benedict’s reaction
d. Lamberts reaction
c
Benedict’s reaction:
The 𝐂𝐮𝟐+ in copper sulfate are reduced by ________ and other
reducing agents to 𝐂𝐮+ in the presence of _______ and an/a _______
environment
Choices:
- glucose
- heat
- alkaline
Glucose
Heat
Alkaline
Copper reduction is a specific test because glucose is the only one that can catalyze the initial reaction
T or F
F
Non specific test since glucose is not the only one that causes this reaction
Ci(+) + Phosphomolybdic acid —-> Phosphomolybdenum
a. Folin-Wu
b. Nelson-Somogyi
c. Neocuproine
a
Ci(+) + arseonmolybdic acid —-> arsenomolybdenum
a. Folin-Wu
b. Nelson-Somogyi
c. Neocuproine
b
Folin-Wu and Nelson-Somogyi is a ________ reaction
a. Simple complex formation
b. Redox reaction
c. Transferases
d. Hydrolayses
b
Phosphomildbdenum and Arsenomolybdenum Produces _______ color upon reaction
a. Yellow
b. Blue
c. Green
d. Red
b
The color produced by Phosphomildbdenum, Arsenomolybdenum, and neocuproine is directly proportional to the level of Cuprous ions
T or F
T
Neocuproine is a simple complex formation between Cuprous ion and
neocuproine
T or F
T
Cuprous-neocuproine complex is yellow-orange in color
a. Blue-Green
b. Yellow-orange
c. Red-orange
d. Violet
b
Ferricyanide is reduced by _________ to ferrocyanide
Glucose
Ferricyanide (Colorless) is reduced to ferrocyanide (yellow-orange)
T or F
F
Baligtad color
Ferric Reduction is also called as Inverse colorimetry or _____________
a. Hagedorn Jensen method
b. Velvet Crow method
c. Crevanille method
d. Schiff’s method
a
Most specific, popular, and bes among all chemical methods
a. Copper reduction
b. Ferric Redcution
c. Condensation
c
Condensation is affected by oxidizing and reducing agent
T or F
F
Not affected
Glucose + o-toluidine ——> Schriff’s base (green)
a. Copper reduction
b. Ferric Redcution
c. Condensation
c
In condensation, the color is direclty proportional to the level of glucose
T or F
T
Which of this is not chemical method?
a. Copper reduction
b. Hexokinase
c. Condensation
d. Ferric reduction
b
Most popular and most commonly used enzymatic method?
a. Glucose oxidase
b. Hexokinase
c. Glucose dehydrogenase
a
β-D-glucose + O2 + H2O –(Glucose oxidase)–> Gluconic acid + H2O2
a. Glucose oxidase
b. Hexokinase
c. Glucose dehydrogenase
a
Oxidizing agent for Glucose oxidase?
Hydrogen peroxide
H2O2 + chromogen oxidized –(Peroxidase)–>
chromogen + H2O
a. Peroxidase-couple/Trinder
b. Polargraphic
a
Measurement of the degree of O2 consumption using a pO2 (electrode)
a. Peroxidase-couple/Trinder
b. Polargraphic
b
Commonly used detection technique in Clinical Chemistry
a. Peroxidase-couple/trinder reaction
b. Polarographic
a
Most common chromagen in Trinder reaction?
a. 4-aminophenozone
b. 4-aminophenol
c. 4-amino-benzaldehyde
d. 4-amino acid
a
Most common reducing agent that can cause False decrease
Ascorbic acid
Strong Oxidizing agent in trinders reaction causes false _______
Increase
H2O2 + 4-aminophenozone –(Peroxidase)—> quinonimine + H2O
What is the color of quinonimine and its absorbance?
red purple
500nm
Polargraphic is not affected by reducing agent
T or F
T
Measures the amount of oxygen consumed in the reaction by detecting the amount of oxygen left
a. Trinder reaction
b. Polarographic
a
Glucose + ATP –(hexokinase)–> glucose-6-PO4 +ADP
Gucose-6-PO4 +NADP –(G6PD)–> 6-PG+ NADPH
a. Trinder reaction
b. Hexokinase
c. Glucose dehydrogenase
b
Reference method for Hexokinase is coupling reaction which is highly specific
T or F
T
If hemolyzed / Icteric sample is used for Hexokinase, this cause False ________
decrease
Involves phosphorylation of Glucose
a. Glucose oxidase
b. Hexokinase
c. Glucose dehydrgenase
b
What is the coupling enzyme for Hexokinase?
G6PD
The end product of Hexokinase is NADPH
T or F
T
What is the absorbance of NADPH? colorimetric or non colorimetric?
340nm
Noncolorimetric (Since it is UV)
Glucose + NAD –(Glucose dehydrogenase) –> Gluconolactone + NADH
a. Glucose oxidase
b. Hexokinase
c. Glucose dehydrgenase
c
Glucose dehydrogenase is a non colorimetric method
T or F
T
Absorbance of NADH
340nm
Since glucose dehydrogenase is a non-colorimetric method, what dye is used to enable colorimetric spectrophotometric measurement?
a. Formazan dye
b. Zark’s dye
c. Methylene blue
d. Tetrazolium dye
d. Tetrazolium dye
NADH + tetrazolium –(Diaphorase)–> NAD + formazan
Colorimetric method for Glucose dehydrogenase
T or F
T
What is the color for formazan?
BLue
Glucose dehydrogenase:
Highly specific for glucose, not subject to interference from substances normally found in serum and provides results in close agreement with hexokinase method
T or F
T
Glucose dehydrogenase is not commonly used to except in glucose POCT (Glucometer)
T or F
T
