What is spectrophotometry?

It is a method to measure how much a chemical substance absorbs light by measuring the intensity of light as a beam of light passes through a sample solution.

What is chromatography in simple words?

is a process for separating components of a mixture. To get the process started, the mixture is dissolved in a substance called the mobile phase, which carries it through a second substance called the stationary phase.

What is a chromatogram?

is the trace generated by the detector signal and requires a carefully controlled flow rate of the carrier gas (mobile phase) and a carefully controlled temperature of the column (stationary phase) to yield repeatable results.

What are the 4 types of chromatography?

1. gas chromatography
2. high-performance liquid chromatography
3. thin-layer chromatography
4. paper chromatography

Paper Chromatography

compound spotted directly on cellulose paper

Method of paper Chromatography

separating a mixture of different colors. The liquid soaks through the paper and carries the mixture with it. Some substances are carried faster than others so the substances are separated along the paper

Thin Layer Chromatography (TLC)

-rapid check of reactions or mixtures

-is a method for separating non-volatile mixtures.

-the experiment is carried out on a sheet of glass, plastic, or aluminum foil that has been lightly covered in an adsorbent substance. Typically, silica gel, cellulose, or aluminum oxide are the materials used.

What are the 3 main types of liquid chromatography?

1. thin layer chromatography
2. paper chromatography
3. column chromatography

what is liquid chromatography or LC?

chromatographic technique in which the mobile phase is a liquid

What is the mobile phase and the stationary phase of liquid chromatography?

The mobile phase is a solution (such methanol, acetone, acetonitrile, water,… ) which transport our components to column (stationary phase)

What are hydrates?

substances that contain water in the form of H₂O molecules.

What are anhydrous?

substances that contain no water

what is a hygroscopic material?

a substance that has the ability to adsorb and absorb moisture or water from the surrounding environment

what is a desiccant material?

drying agents

Beer-Lambert law formula

Au X (Cs/As) = Cu

Au = absorbance of unknown

Cu = concentration of unknown

As = absorbance of standard

A = absorbance

This formula is applied to assays that exhibit linear relationships between changes in absorbance with changes in concentration to calculate the concentration of the unknown sample.

what is the beer-lambert law?

states that there is a linear relationship between the concentration and the absorbance of the solution, which enables the concentration of a solution to be calculated by measuring its absorbance.

what is an anticoagulant?

commonly added to collection tubes either to maintain blood in the fluid state for hematological testing or to obtain suitable plasma for coagulation and clinical chemistry analyses.

what is a class A fire?

involve ordinary combustible materials, such as cloth, wood, paper, rubber, and many plastics.

what is a class B fire?

fires are ones where flammable liquids and/or gases are involved. They are the fuel source in the fire triangle (fuel, heat, oxygen + chemical reaction).

what is a class C fire?

fires involve electrical equipment, such as appliances, wiring, circuit breakers and outlets.

The mean is considered the________?

the average

The median is considered the_______?

the middle

the mode is considered the_____?

the most common number that appears in your set of data.

the total allowable error is

is a pre-determined number that can be tolerated without invalidating the clinical usefulness of the analytic result.

Which of the following lamps provides a continuous spectrum of radiant energy in the visible, near IR, and near UV regions of the spectrum?

Tungsten-filament

Which of the following isolates light within a narrow region of the spectrum?

Monochromator

A monochromator is a ____________

device for selecting a narrow band of wavelengths from a continuous spectrum.

Which of the following is not descriptive of a photomultiplier tube?

A. Emits electrons proportionally to initial light absorbed
B. Must be shielded from stray light
C. Cannot be used with a chopper
D. Amplifies the initial signal received

C. Cannot be used with a chopper

What is a photomultiplier tube?

are extremely sensitive detectors of light in the ultraviolet, visible, and near-infrared ranges of the electromagnetic spectrum

Which of the following is false about a photomultiplier tube?

A. Converts radiant energy (light) to electrical energy (current)
B. Amplifies the current significantly
C. Has a very rapid response time
D. Is composed of an iron plate and a layer of selenium

D. Is composed of an iron plate and a layer of selenium

Which type of photodetector employs a linear arrangement that allows it to respond to a specific wavelength resulting in complete UV/visible spectrum analysis?

A. Photomultiplier tube
B. Phototube
C. Barrier layer cell
D. Photodiode array

D. Photodiode array

what is a photodiode?

it is a form of light sensor that converts light energy into electrical energy (voltage or current)

When performing spectrophotometer quality assurance checks, what is the holmium oxide glass filter used to assess?

A. Linearity
B. Stray light
C. Absorbance accuracy
D. Wavelength accuracy

D. Wavelength accuracy

In spectrophotometric analysis, what is the purpose of the reagent blank?

A. Correct for interfering chromogens
B. Correct for lipemia
C. Correct for protein
D. Correct for color contribution of the reagents

D. Correct for color contribution of the reagents

In regard to bichromatic analysis, which of the following is false?

A. Absorbance is measured at the spectral absorbance peak for a blank
and the sample using the same wavelength.
B. Eliminates background interferences
C. Sample concentration determined from difference in two measured absorbances
D. Functions as a reference blank for each sample

A. Absorbance is measured at the spectral absorbance peak for a blank and the sample using the same wavelength.

The bandpass of a spectrophotometer is 10 nm. If an instalment is set at 540 nm, the wavelengths that are permitted to impinge on the sample will be within what wavelength range?

A. 530-540 nm
B. 530-550 nm
C. 535-545 nm
D. 540-550 nm

C. 535-545 nm

540 ± 5 nm (10-nm bandpass) will be equivalent to a wavelength range of 535-545 nm.

Which of the following formulas is an expression of the Beer-Lambert law that is routinely applied to spectrophotometric analysis?

A. Au X (Cs/As) = Cu
B. Cu X (Cs/As)= Au
C. As X (Cs/Cu) = Au
D. A = 2 - log %T

A. Au X (Cs/As) = Cu

In spectrophotometry, which of the following is a mathematical expression of the relationship between absorbance and transmittance?

A. A = abc
B. Au/Cu = As/Cs
C. A = 2 - log %T
D. A = log %T

C. A = 2 - log %T

Which of the following is not a problem inherent in turbidimetry?

A. Variation in particle size of samples
B. Variation in particle size of standards
C. Rate of aggregation or settling of particles
D. Need to maintain a constant and specific temperature

D. Need to maintain a constant and specific temperature

Turbidimetry is the ___________________

measurement of the amount of light blocked by particulate matter in passing through a turbid solution.

Which of the following may be associated with reflectance spectrophotometry as it relates to the dry reagent slide technique?

A. Light projected to the slide at 180-degree angle
B. Dye concentration directly proportional to reflectance
C. Unabsorbed, reflected light detected by photodetector
D. Reflectance values are linearly proportional to transmission values

C. Unabsorbed, reflected light detected by photodetector

Fluorometers are designed so that the path of the exciting light is at a right angle to the path of the emitted light. What is the purpose of this design?

A. Prevent loss of emitted light
B. Prevent loss of the excitation light
C. Focus emitted and excitation light upon the detector
D. Prevent excitation light from reaching the detector

D. Prevent excitation light from reaching the detector

Because the right-angle configuration does not prevent loss of the exciting or the emitted light.

Which of the following represents a primary advantage of performing fluorometric over absorption spectroscopic methods of analysis?

A. Increased specificity and increased sensitivity
B. Increased specificity and decreased sensitivity
C. Purity of reagents used not as critical
D. Ease of performing assays

A. Increased specificity and increased sensitivity

Which of the following may be associated with fluorescence polarization?

A. Plane-polarized light is used for sample excitation.
B. Small molecular complexes show a greater amount of polarization.
C. It is a heterogeneous technique employed in fluorophore-ligand immunoassays.
D. Polarized light detected is directly proportional to concentration of ligand in sample.

A. Plane-polarized light is used for sample excitation.

Which of the following may be associated with bioluminescence?

A. Light emission produced due to enzymatic oxidation of a substrate
B. Less sensitive than direct fluorescent assays
C. Electron excitation caused by radiant energy
D. Employs a radioactive label

A. Light emission produced due to enzymatic oxidation of a substrate

Nephelometry is based on the measurement of light that is

A. Absorbed by particles in suspension
B. Scattered by particles in suspension
C. Produced by fluorescence
D. Produced by excitation of ground-state atoms

B. Scattered by particles in suspension

Which of the following instruments is used in the clinical laboratory or in
reference laboratories to detect beta and gamma emissions?

A. Fluorometer
B. Nephelometer
C. Scintillation counter
D. Spectrophotometer

C. Scintillation counter

Which of the following best describes chemiluminescence?

A. Electron excitation caused by radiant energy
B. Enzymatic oxidation of a substrate produces light emission
C. Chemical energy excites electrons that emit light upon return to ground state
D. Employs a fluorescent label that produces light

C. Chemical energy excites electrons that emit light upon return to ground state

In assaying an analyte with a single-beam atomic absorption spectrophotometer, what is the instrument actually measuring?

A. Intensity of light emitted by the analyte on its return to the ground state
B. Intensity of light that the analyte absorbs from the hollow-cathode lamp
C. Intensity of light that the analyte absorbs from the flame
D. Intensity of the beam from the hollowcathode lamp after it has passed through the analyte-containing flame

D. Intensity of the beam from the hollowcathode lamp after it has passed through the analyte-containing flame

What is the function of the flame in atomic absorption spectroscopy?

A. Absorb the energy emitted from the metal analyte in returning to ground state
B. Supply the thermal energy needed to excite the metal analyte
C. Bring the metal analyte to its ground state
D. Supply the light that is absorbed by the metal analyte

C. Bring the metal analyte to its ground state

Most atomic absorption spectrophotometers incorporate a beam chopper and a tuned amplifier. The purpose of these components is to avoid errors that would be caused by

A. Variations in flame temperature
B. Deterioration of the hollow-cathode lamp
C. Stray light from the hollow-cathode lamp
D. Measurement of light emitted by the analyte

D. Measurement of light emitted by the analyte

In potentiometry, which of the following is considered the standard electrode?

A. Hydrogen electrode
B. Calcium electrode
C. Potassium electrode
D. Copper electrode

A. Hydrogen electrode

In an electrolytic cell, which of the following is the half-cell where reduction takes place?

A. Anode
B. Cathode
C. Combination electrode
D. Electrode response

B. Cathode

Mercury covered by a layer of mercurous chloride in contact with saturated potassium chloride solution is a description of which of the following types of electrodes?

A. Sodium
B. Calomel
C. Calcium
D. Silver/silver chloride

B. Calomel

When a pH-sensitive glass electrode is not actively in use, in what type of solution should it be kept?

A. Tap water
B. Physiologic saline solution
C. The medium recommended by the manufacturer
D. A buffer solution of alkaline pH

C. The medium recommended by the manufacturer

When measuring K+ with an ion-selective electrode by means of a liquid ionexchange membrane, what antibiotic will be incorporated into the membrane?

A. Monactin
B. Nonactin
C. Streptomycin
D. Valinomycin

D. Valinomycin

What are the principles of operation for a chloride analyzer that generates silver ions as part of its reaction mechanism?

A. Potentiometry and amperometry
B. Amperometry and polarography
C. Coulometry and potentiometry
D. Amperometry and coulometry

D. Amperometry and coulometry

When quantifying glucose using an amperometric glucose electrode system, which of the following is not a component of the system?

A. Product oxidation produces a current
B. Hydrogen peroxide formed
C. Hexokinase reacts with glucose
D. Platinum electrode

C. Hexokinase reacts with glucose

To calibrate the pH electrode in a pH/ blood gas analyzer, it is necessary that

A. The barometric pressure be known and used for adjustments
B. Calibrating gases of known high and low concentrations be used
C. The calibration be performed at room temperature
D. Two buffer solutions of known pH be used

D. Two buffer solutions of known pH be used

The measurement of CO2 in blood by means of a PCO2 electrode is dependent on the

A. Passage of H+ ions through the membrane that separates the sample and the electrode
B. Change in pH because of increased carbonic acid in the electrolyte surrounding the electrodes
C. Movement of bicarbonate across the membrane that separates the sample and the electrode
D. Linear relationship between PCO2 in the sample and measured pH

B. Change in pH because of increased carbonic acid in the electrolyte surrounding the electrodes

The measurement of oxygen in blood by means of a PO2 electrode involves which of the following?

A. Wheatstone bridge arrangement of resistive elements sensitive to oxygen concentration
B. Direct relationship between amount of oxygen in the sample and amount of current flowing in the measuring system
C. Change in current resulting from an increase of free silver ions in solution
D. Glass electrode sensitive to H+ ion

B. Direct relationship between amount of oxygen in the sample and amount of current flowing in the measuring system

Which of the following blood gas parameters are measured directly by the blood gasanalyzer electrochemically as opposed to being calculated by the instrument?

A. pH, HCO-3, total CO2
B. PCO2, HCO-3, PO2
C. pH, PCO2, PO2
D. PO2, HCO-3, total CO2

C. pH, PCO2, PO2

Which formula correctly describes the relationship between absorbance and %T ?

A. A = 2 - log %T
B. A = log 1/T
C. A = -log T
D. All of these options

D. All of these options

Which of the following techniques is more commonly used to measure vitamins?

A. High-performance liquid chromatography
B. Spectrophotometry
C. Nephelometry
D. Microbiological

A. High-performance liquid chromatography

In the United States, most cases of scurvy occur in children between the ages of 7 months to 2 years. Scurvy is a disease caused by a deficiency in which of the following?

A. Vitamin A
B. Vitamin C
C. Vitamin D
D. Vitamin K

B. Vitamin C

Vitamins A, D, E, and K are classified as __________?

fat-soluble vitamins.

Vitamin C are classified as ____________?

water-soluble vitamins and as such are not lipid compounds.

The term "lipid" encompasses a wide variety of compounds characterized as being insoluble in water but soluble in nonpolar solvents. Which of the following vitamins is not classified as fat soluble?

A. Vitamin A
B. Vitamin C
C. Vitamin D
D. Vitamin E

B. Vitamin C

Measuring which of the following compounds is useful in the diagnosis
of steatorrhea?

A. Vitamin B12
B. Vitamin C
C. Carotenoids
D. Folic acid

C. Carotenoids

What is steatorrhea?

it is an increase of fat excretion in the stools. Another term for it is called fat malabsorption.

Carotenoids are __________?

a group of fat-soluble compounds that are precursors of vitamin A (retinol). They are not synthesized in humans, and their absorption depends on intestinal fat absorption. Therefore, the serum carotene level is sometimes used as a simple screening test for steatorrhea.

Which of the following is another name for vitamin B12?

A. Retinol
B. Pyridoxine
C. Cyanocobalamin
D. Riboflavin

C. Cyanocobalamin

Which of the following is not associated with vitamin B12?

A. Insoluble in water
B. Intrinsic factor
C. Schilling test
D. Pernicious anemia

A. Insoluble in water

Vitamin B12 is a _____________?

water-soluble vitamin.

Which of the following tissues is important in vitamin D metabolism?

A. Skin
B. Spleen
C. Pancreas
D. Thyroid

A. Skin

A deficiency in which of the following leads to increased clotting time and may result in hemorrhagic disease in infancy?

A. Riboflavin
B. Pyridoxine
C. Tocopherols
D. Menaquinone

D. Menaquinone

Menaquinone is __________?

Vitamin K₂

Tocopherols is _________?

Vitamin E

Pyridoxine is ___________?

Vitamin B-6

Riboflavin is ___________ ?

Vitamin B2

In absorption spectrophotometry:

A. Absorbance is directly proportional to
transmittance
B. Percent transmittance is directly proportional to concentration
C. Percent transmittance is directly proportional to the light path length
D. Absorbance is directly proportional to concentration

A. Absorbance is directly proportional to
transmittance

Which wavelength would be absorbed strongly by a red-colored solution?

A. 450 nm
B. 585 nm
C. 600 nm
D. 650 nm

A. 450 nm

a solution that looks red in color would probably absorb most strongly in the wavelength range ____________?

400–600nm

A green-colored solution would show highest transmittance at:

A. 475 nm
B. 525 nm
C. 585 nm
D. 620 nm

B. 525 nm

SITUATION: A technologist is performing an enzyme assay at 340 nm using a visible-range spectrophotometer. After setting the wavelength and adjusting the readout to zero %T with the light path blocked, a cuvette with deionized water is inserted. With the light path fully open and the 100%T control at maximum, the instrument readout will not rise above 90%T. What is the most appropriate first course of action?

A. Replace the source lamp
B. Insert a wider cuvette into the light path
C. Measure the voltage across the lamp terminals
D. Replace the instrument fuse

A. Replace the source lamp

Which monochromator specification is required in order to measure the true absorbance of a compound having a natural absorption bandwidth of 30 nm?

A. 50-nm bandpass
B. 25-nm bandpass
C. 15-nm bandpass
D. 5-nm bandpass

D. 5-nm bandpass

Because the narrower the bandpass, the greater the photometric resolution.

Which photodetector is most sensitive to low levels of light?

A. Barrier layer cell
B. Photodiode
C. Diode array
D. Photomultiplier tube

D. Photomultiplier tube

How does photomultiplier tube work?

The photomultiplier tube uses dynodes of increasing
voltage to amplify the current produced by the photosensitive cathode. It is 10,000 times as sensitive as a barrier layer cell, which has no amplification. A photomultiplier tube requires a DC-regulated lamp because it responds to light fluctuations caused by the AC cycle

Which condition is a common cause of stray light?

A. Unstable source lamp voltage
B. Improper wavelength calibration
C. Dispersion from second-order spectra
D. Misaligned source lamp

C. Dispersion from second-order spectra

Which type of filter is best for measuring stray light?

A. Wratten
B. Didymium
C. Sharp cutoff
D. Neutral density

C. Sharp cutoff

Which of the following materials is best suited for verifying the wavelength calibration of a spectrophotometer?

A. Neutral density filters
B. Potassium dichromate solutions traceable to the National Bureau of Standards reference
C. Wratten filters
D. Holmium oxide glass

D. Holmium oxide glass

The half-band width of a monochromator is defined by:

A. The range of wavelengths passed at 50% maximum transmittance
B. One-half the lowest wavelength of optical purity
C. The wavelength of peak transmittance
D. One-half the wavelength of peak absorbance

A. The range of wavelengths passed at 50% maximum transmittance

The reagent blank corrects for absorbance caused by:

A. The color of reagents
B. Sample turbidity
C. Bilirubin and hemolysis
D. All of these options

A. The color of reagents

Which instrument requires a highly regulated DC power supply?

A. A spectrophotometer with a barrier layer cell
B. A colorimeter with multilayer interference filters
C. A spectrophotometer with a photomultiplier tube
D. A densitometer with a photodiode detector

C. A spectrophotometer with a photomultiplier tube

What happens If the PH of blood decreases from 7.4 to 7.1?

[H+] is doubled

When the measure of an [k] acid strength increase so does __________?

[H⁺ ]hydrated hydronium ion

What happens If the blood increases from 7.4 to 7.7?

[H+] is halved

What does a blood pH of 7.4 correspond to in nM?

40 nM [H+]. This is the mean of the normal range (44 to 36 nM)

What is the normal pH of blood's range?

7.36 to 7.44

What is the condition called when the pH of blood rises above 7.44 ([H+] < 36 nM)?

alkalemia

What is the condition called when the pH decreases below 7.36 ([H+] > 44 nM)?

acidemia

What does the suffix -emia mean?

blood; usually to an abnormal concentration in blood.

Over the pH range of 7.20 to 7.50 what is the change in nM [H+] for every change in 0.01 pH unit?

1 nm [H+] in the opposite direction.

Which of the following technique measures light scattered and has a following light source placed at 90 degrees from the incident light?

A. Chemiluminescence

B. Atomic absorption spectrophotometry

C. Nephelometry

D. Turbidity

C. Nephelometry

Nephelometry is ___________?

a technique that measures light scattered by particular in suspension with a detector at an angle to the incident light (often 45 or 90 degrees)

Which of the following may be associated with reflectance spectrophotometry as it relates to the drying reagent slide technique?

A. Light projected to the slide at 180- degree angle

B. Dye concentration directly proportional to reflectance

C. Unabsorbed, reflected light detected by photodetector

D. Reflectance values are linearly proportional to transmission value

C. Unabsorbed, reflected light detected by photodetector

What indicator electrode uses a membrane made of dioxides the combine with result in an ion exchange with the analytes of interest in a patent sample?

A. Glass

B. Liquid

C. Silver-silver chloride

D. Calomel

A. Glass

An example of glass electrode is the PH electrode.

Which of the following method allows for the separation for the separation of charged particles based on their rates of migration in an electric field?

A. Rheopheresis

B. Electrophoresis

C. Electroendosmosis

D. Ion Exchange

B. Electrophoresis

Electrophoresis is ____________?

method of separating charged particles by their rates of migration in an electric field.

Electroendosmosis is ____________?

the movement of water and the contents within through a porous material when under the influence of an electric charge

Which of the following techniques is based on electro-osmotic flow?

A. Capillary electrophoresis
B. Zone electrophoresis
C. Iontophoresis
D. Isoelectric focusing

A. Capillary electrophoresis

In isoelectric focusing electrophoresis, am-pholytes create a pH gradient where:

The higher pH gradient is toward the cathode

In serum protein electrophoresis, when a buffer solution of pH 8.6 is used, which of the following characterizes the proteins?

A. Exhibit net negative charge
B. Exhibit net positive charge
C. Exhibit charge neutrality
D. Migrate toward the cathode

A. Exhibit net negative charge

At the alkaline pH, the serum proteins have a net negative charge. Therefore the negatively charged serum proteins migrate toward the anode.

What is an anode?

the positively charged electrode

What is cathode?

the negatively charged electrode

Which of the following characteristics will a protein have at its isoelectric point?

A. Net negative charge
B. Net positive charge
C. Net zero charge
D. Mobility

C. Net zero charge

The isoelectric point (pI) of a protein refers ___________?

to the pH at which the number of positive charges on the protein molecules equals the number of negative charges, causing the protein to have a net charge of zero.

What dye may be used for staining protein bands following electrophoresis?

A. Fat red 7B
B. Sudan blackB
C. Ponceau S
D. Oil redO

C. Ponceau S

When electrophoresis is performed, holes appear in the staining pattern, giving the stained protein band a doughnut-like appearance. What is the probable cause of this problem?

A. Protein denatured and will not stainproperly
B. Ionic strength of the buffer was toohigh
C. Protein reached its isoelectric pointand precipitated out
D. Protein concentration was too high

D. Protein concentration was too high

What is the purpose of using ampholytesin isoelectric focusing?

A. Maintain the polyacrylamide gel ina solid state
B. Maintain the protein sample ina charged state
C. Maintain the pH of the buffersolution
D. Establish a pH gradient in the gel

D. Establish a pH gradient in the gel

Which of the following is an electrophoretic technique employing a ph gradient that separates molecules with similar isoelectric points?

A. Zone electrophoresis
B. High-resolution electrophoresis
C. Isoelectric focusing
D. Immunoelectrophoresis

C. Isoelectric focusing

Given the following information on a particular compound that has been visualized by means of thin-layer chromatography, calculate the Rf of the compound.
Distance from origin to spot center = 48mm
Distance from spot center to solvent front = 93 mm
Distance from origin to solvent front = 141mm

A. 0.29
B. 0.34
C. 0.52
D. 0.66

B. 0.34

=origin to spot center/origin to solvent front

=48/141=.34

To achieve the best levels of sensitivity and specificity, to what type of detector system could a gas chromatograph be coupled?

A. UV spectrophotometer
B. Bichromatic spectrophotometer
C. Mass spectrometer
D. Fluorescence detector

C. Mass spectrometer

Which of the following instruments has a sample-introduction system, solvent delivery system, column, and detector as components?

A. Atomic absorption spectrometer
B. Mass spectrometer
C. High-performance liquid chromatograph
D. Nephelometer

C. High-performance liquid chromatograph

Which type of elution technique may be used in high-performance liquid chromatography?

A. Amphoteric
B. Isoelectric
C. Gradient
D. Ion exchange

C. Gradient

Which of the following statements best describes discrete analysis?

A. Each sample-reagent mixture is handled separately in its own reaction vessel.
B. Samples are analyzed in a flowing stream of reagent.
C. Analyzer must be dedicated to measurement of only one analyte.
D. It does not have random access capability.

A. Each sample-reagent mixture is handled separately in its own reaction vessel.

Which of the following chromatography systems may be described as having a stationary phase that is liquid absorbed on particles packed in a column and a liquid moving phase that is pumped through a column?

A. Thin-layer
B. High-performance liquid
C. Ion-exchange
D. Gas-liquid

B. High-performance liquid

Which of the following chromatography systems is characterized by a stationary phase of silica gel on a piece of glass and a moving phase of liquid?

A. Thin-layer

B. Ion-exchange

C. Gas-liquid

D. Partition

A. Thin-layer

Which of the following does not apply to gas-liquid chromatography?

A. Separation depends on volatility of the sample.
B. Separation depends on the sample's solubility in the liquid layer of the stationary phase.
C. Stationary phase is a liquid layer adsorbed on the column packing.
D. Mobile phase is a liquid pumped through the column.

D. Mobile phase is a liquid pumped through the column.

Ion-exchange chromatography separates solutes in a sample based on the

A. Solubility of the solutes
B. Sign and magnitude of the ionic charge
C. Adsorption ability of the solutes
D. Molecular size

B. Sign and magnitude of the ionic charge

Which parameter is used in mass spectrometry to identify a compound?

A. Ion mass-to-charge ratio
B. Molecular size
C. Absorption spectrum
D. Retention time

A. Ion mass-to-charge ratio

What is the x-mass on the mass spectrum?

A. Mass

B. Mass/energy

C. Mass/charge

D. Charge

C. Mass/charge

A mass spectrum is an __________?

Intensity vs. mass/ charge ration plot representing an analysis.

Which chromatography system is commonly used in conjunction with mass spectrometry?

A. High-performance liquid
B. Ion-exchange
C. Partition
D. Gas-liquid

D. Gas-liquid

Which of the following may be a sampling source of error for an automated instrument?

A. Short sample
B. Air bubble in bottom of sample cup
C. Fibrin clot in sample probe
D. All the above

D. All the above

Checking instrument calibration,temperature accuracy, and electronic parameters are part of

A. Preventive maintenance
B. Quality control
C. Function verification
D. Precision verification

C. Function verification

For which of the following laboratory instalments should preventive maintenance procedures be performed and recorded?

A. Analytical balance
B. Centrifuge
C. Chemistry analyzer
D. All the above

D. All the above

Which hemoglobin may be differentiated from other hemoglobins on the basis of its resistance to denature in alkaline solution?

A. A1
B. A2
C. C
D. F

D. F

In the Clark electrode, for every molecule of oxygen reduced at the cathode, how many electrons of current flow?

A. 1

B. 2

C. 4

D. 8

C. 4

With each molecule of oxygen that is reduced at the cathode, it causes four electrons of the current flow

When performing electrophoresis at pH 8.6, which hemoglobin molecule migrates the fastest on cellulose acetate toward the anode?

A. A1
B. A2
C. F
D. S

A. A1

Hemoglobin A migrates the fasts toward anode, followed by hemoglobin F and S. Then A₂ and C.

When using EMIT, the enzyme is coupled to

A. Antibody
B. Antigen
C. Substrate
D. Coenzyme

B. Antigen

Which of the following is not associated with the enzyme-multiplied immunoassaytechnique (EMIT)?

A. Is a homogeneous enzyme immunoassay
B. Determines antigen concentration
C. Employs a labeled reactant
D. Enzyme reacts with drug in serum sample

D. Enzyme reacts with drug in serum sample

Which of the following stimulates the production of singlet oxygen at the surface of the sensitizer particle in a luminescent oxygen channeling immunoassay?

A. Radiant energy
B. Heat energy
C. Enzymatic reaction
D. Fluorescent irradiation

A. Radiant energy

Singlet oxygen reacting with a precursor chemiluminescent compound to form a decay product whose light energizes a fluorophore best describes

A. Fluorescent polarization immunoassay
B. Enzyme-multiplied immunoassay technique
C. Electrochemiluminescence immunoassay
D. Luminescent oxygen channeling immunoassay

D. Luminescent oxygen channeling immunoassay

pre-analytical variables in lab testing include:

specimen acceptability

which of the following is NOT a potential source of post-analytical errors?

labeling the specimen at the nurse's station

a pre-analytical error can be introduced by:

vigorously shaking the blood tube to prevent clotting

the most important diagnosis and therapeutic mgmt decision tool used to interpret test results is:

reference intervals

a CC (clean-catch) urine is submitted to the lab for routine UA/Culture. the routine UA is done first, and 3 hours later, the specimen is sent to micro for culture. the specimen should:

rejected for time delay

Urine samples should be examined within 1 hour of voiding because:

bacterial contamination will cause alkalinization of the urine

a urine comes to the lab 7 hours after it is collected. it is acceptable for culture only if the specimen has been stored:

at 4-7C

which of the following statements about analytical errors is true?

analytical errors are not obvious to providers

the first procedure to be followed if the blood gas instrument is out of control for all parameters is:

recalibrate and repeat controls

upon completion of a run of cholesterol tests, the tech recognizes that the controls are not within the 2 standard deviations confidence range. what is the appropriate course of action?

run new set of controls and repeat specimens

Using a common labeling system for hazardous material identification such as HMIS or NFPA 704, the top red quadrant represents which hazard?
a reactivity
b special reactivity
c health
d flammability

flammability