PT AUBF Lab-Module 4

reagent strips

provide a simple, rapid means of performing chemical analysis of urine

when the absorbent pads come in contact with urine

How does chemical reaction takes place during reagent strip test method?

if the color reactions are read too early or too late

When are inaccurate interpretations occur during reagent strip test method?

stated time

For best semi-quantitative results, the manufacturer's _____ should be followed.

moisture, volatile chemicals, heat, light

What causes deterioration of the reagent strips

good light source

essential for accurate interpretation of color reactions

The strips must be held close to the color charts without touching the chart.

How should you interpret the color reactions?

protein error of pH indicators

The protein reaction of the reagent strips is based on ________

protein error of pH indicators

The point of color change of some pH indicators is different in the presence of protein from that observed in the absence of protein, because proteins act as hydrogen ion acceptors at a constant pH. This concept explains what?

green color; pH of 3

The development of any ______ in the protein reagent pad is due to the presence of protein at a constant pH of _______.

glucose oxidase, peroxidase and chromogen

The glucose test is based on the enzymatic reaction between what reagents?

Glucose oxidase

What oxidizes glucose to gluconic acid and at the same time reduces atmospheric oxygen to hydrogen peroxide?

gluconic acid; hydrogen peroxide

Glucose oxidase oxidizes glucose to _________ and at the same time reduces atmospheric oxygen to ________hydrogen peroxide.

green to brown

The extent to which the chromogen is oxidized determines the color which is produced, ranging from ________

peroxidase-like activity

Reagent strip tests for blood (hemoglobin, myoglobin) in urine are based on the _________ of the heme portion of hemoglobin molecules.

Peroxidase

_______ catalyzes the release of oxygen from the organic peroxide in the reagent strip.

oxygen

Peroxidase catalyzes the release of _____ from the organic peroxide in the reagent strip.

reduced form of the chromogen

The released oxygen in the blood test on reagent strip reacts with the _______, producing an oxidized chromogen.

oxidied chromogen

The released oxygen in the blood test on reagent strip reacts with the reduced form the chromogen producing an __________.

orange to greeen to dark blue

The reaction of blood reagent strip test results to a color change of _______

60 seconds

During blood reagent strip test, any green spots or green color development on the reagent area within _____ is significant and the urine specimen should be examined further.

nitroprusside and acetoacetic acid

Ketone reagent strip test is based on ketones reacting with ______ and ______.

light pink

Negative color result for ketone reagent strip test

darker pink or purple color

Positive color result for ketone reagent strip test

fasting, pregnancy, and frequent strenous exercise

Detectable ketone levels may occur in urine during physiological stress conditions such as ________.

urobilinogen

useful in the diagnosis of liver function disorders.

p-dimethyl-aminobenzaldehyde and urobilinogen

Reagent strip test for urobilinogen is based on a modified Ehrlich reaction between ________ and ________ in strongly acidic medium.

Ehrlich reaction

Reagent strip test for urobilinogen is based on a modified ______ between p-dimethyl-aminobenzaldehyde and urobilinogen in strongly acidic medium to produce a pink to red color.

acidic medium

What medium is used during urobilinogen test?

pink to red color

Color range during urobilinogen reagent strip test

Nitrite test

rapid, indirect method for the detection of significant & asymptomatic bacteriuria.

nitrate to nitrite; Gram negative bacteria

Reagent strips for the detection of nitrite in urine depends on the conversion of ____ to _____ by the action of ______ in urine.

p- arsanilic acid; diazonium compound

In an acidic medium, nitrite in the urine reacts with _______ acid to form a _______.

quinoline compound (1-naphthyl-ethelynediamine)

The diazonium compound couples with _______ to produce pink color.

Neutrophils

most common leukocyte seen in urine, is normally present in low numbers.

esterases

Neutrophils contain enzymes known as _______

urinary tract infection

Increased numbers of neutrophils usually indicate the presence of ________.

derivatized pyrazole amine acid ester; derivatized hydroxy pyrazole; diazonium salt

During leukocyte reagent strip test, the esterases cleave a ______to liberate a ________. This pyrazole reacts with _________ to produce beige pink to purple color.

methyl red and bromthymol blue; 5-9

pH reagent strip test use a double indicator system of ______ and _____ that measure urine pH between _____ to _____.

red orange to yellow; 4.4 to 6.2

The methyl red produces a color change from _____ to ______ in the pH range _____ to _____.

yellow to blue; 6.0-7.6

Bromthymol blue turns from ____ to _____ which indicates pH range of ____ to ____.

touching the edge of the strip against the rim of the container as you withdraw the strip

How should you remove excess urine in the strip?

By immersing them in disinfectant solution before disposing them into infectious wastes

How should you dispose reagent strips?

pH 5-7

Reference value for pH

pH 4.5-8

pH reference value for adults/others

<100mg/dl

Reference value for negative glucose test result

1-14mg/dl

Reference value for protein

0.2-1mg/dl or 3.5-17umol/L

Urobilinogen reference value

1.003-1.035

Specific gravity reference value

orange to blue

Color for positive pH result

yellow to yellow green

Color for negative protein result

Green to green-blue

Color for positive protein result

light pink

Color for negative ketones result

green-brown

Color for positive glucose result

darker pink to purple

Color for positive ketones result

orange

Color for negative blood result

green spots to dark blue

Color for positive blood result

Pinkish tan

Color for positive bilirubin result

Pink

Color for positive urobilinogen result

Pink

Color for positive nitrite result

beige pink-purple

Color for positive leukocyte esterase result

green or yellow green

Color for positive specific gravity result

deep blue

Color for negative specific gravity result

run over

This occurs when excess urine from one test pad flows into an adjacent pad on the reagent strip, leading to inaccurate results.

methyl red and bromothymol blue

Reagent for pH reagent strip test

glucose oxidase, peroxidase, chromogen, buffer

Reagent for glucose reagent strip test

Either tetrabromophenol blue (Multistix) or 3′,3′′,5′,5′′-tetrachlorophenol, 3,4,5,6-tetrabromosulfonphthalein (Chemstrip)

Reagent for protein reagent strip test

nitroprusside and acetoacetic acid

Reagent for ketones reagent strip test

Peroxide and tetramethylbenzidine

Reagent for blood reagent strip test

diazonium salt or diazotized dichloroaniline

Reagent for bilirubin reagent strip test

p-dimethylaminobenzaldehyde (Ehrlich reagent)

Reagent for urobilinogen reagent strip test

p-arsanilic acid and quinoline compound (1-naphthyl-ethelynediamine)

Reagent for nitrite reagent strip test

Indoxylcarbonic acid ester and diazonium salt

Reagents of leukocyte esterase reagent strip test

Polyelectrolyte and bromothymol blue

Reagent for specific gravity URS test