HPLC & OTHER MISC. SEPARATION METHODS

Question 1

most versatile and widely used type of elution chromatography

Answer 1

High – Performance Liquid Chromatography (HPLC)

Question 2

is a process in which dissolved gases are swept out of a solvent by bubbles of an inert, insoluble gas

Answer 2

Sparging

Question 3

elution with a single solvent or solvent mixture of constant composition is termed an __

Answer 3

isocratic elution.

Question 4

in HPLC is one in which the solvent composition remains constant.

Answer 4

isocratic elution

Question 5

in HPLC is one in which the composition of the solvent is changed continuously or in a series of steps.

Answer 5

gradient elution

Question 6

produce a pulse-free delivery whose flow rate is easily controlled

Answer 6

Screw – Driven Syringe type

Question 7

used in almost all commercial instruments

Answer 7

Reciprocating Pump

Question 8

-Used for mobile – phase conditioning

Answer 8

Scavenger Column

Question 9

Removes particulates and other solvent impurities

Answer 9

Guard Column

Question 10

Fractionation is based on molecular size
Powerful technique that is particularly applicable to high – molecular mass species

Answer 10

Size – Exclusion Chromatography

Question 11

Used to separate analytes into their optical isomers using the chiral stationary phase

Answer 11

Chiral Chromatography

Question 12

Such mirror images are called __ .

Answer 12

enantiomers.

Question 13

is a chiral mobile-phase additive or a chiral stationary phase that preferentially complexes one of the enantiomers

Answer 13

chiral resolving agent

Question 14

once called two-dimensional chromatography, although this term has now come to signify the coupling of two chromatographic techniques with different separation mechanisms.

Answer 14

Planar Chromatography

Question 15

used in fractionation of sugar and amino acids

Answer 15

Paper Chromatography

Question 16

sorbent of paper chromatography

Answer 16

Whatman paper

Question 17

it is used for drug testing screening (semiquantitative screening test)

Answer 17

Thin – Layer Chromatography

Question 18

Sample molecule are separated by electro – osmotic flow (EOF)

Answer 18

Capillary Electrophoresis

Question 19

Is a hybrid of HPLC and capillary electrophoresis (CE) that offers some of the best features of the two methods.

Answer 19

Capillary Electrochromatography (CEC)

Question 20

• A system of ensuring accuracy and precision in the laboratory by including quality control reagents in every series of measurement

Answer 20

Quality Control

Question 21

It is the ability of an analytical method to measure the smallest concentration of the analyte of interest

Answer 21

Sensitivity

Question 22

It is the ability of an analytical method to measure only the analyte of interest

Answer 22

Specificity

Question 23

It is the nearness or closeness of the assayed value to the true or target value

Answer 23

Accuracy

Question 24

The ability of an analytical method to give repeated results on the same sample that agree with one another

Answer 24

Precision or Reproducibility

Question 25

The degree by which a method is easily repeated

Answer 25

Practicability

Question 26

The ability of an analytical method to maintain accuracy and precision over an extended period of time during which equipment, reagents, and personnel may change

Answer 26

Reliability

Question 27

True Positive
Is the ability of the test to detect the proportion of individuals with that disease who test positive with the test

Answer 27

Diagnostic Sensitivity

Question 28

True Negative
Is the ability of the test to detect the proportion of individuals without the disease who test negatively for the disease.

Answer 28

Diagnostic Specificity

Question 29

-It is present in all measurements
it is due to chance and can be both positive and negative
It is the basis for varying differences between repeated measurements.

Answer 29

Random Error

Question 30

-Is an error that influences observations consistently in one direction(constant difference)
It is detected as either positive or negative bias
Often related to calibration problems, deterioration of reagents and control materials, unstable and inadequate reagent blanks, contaminated solutions, failing instrumentation and poorly written procedures.

Answer 30

Systematic Error

Question 31

Refers to the difference between the target value and the assay value.
It is independent of sample concentration.

Answer 31

Constant Error

Question 32

Results in greater deviation from the target value due to higher sample concentration.
Exists when the difference between the test method and the comparative method values are proportional to the analyte concentration

Answer 32

Proportional/ Slope/ Percent Error

Question 33

The highest frequency of clerical errors occurs with the use of handwritten labels and request forms

Answer 33

Clerical Error

Question 34

-It occurs when the date set can be accurately described by the SD and the mean.

Answer 34

Gaussian Curve (Bell – Shaped Curve)

Question 35

-It calculates the difference between the QC results and the target means

Answer 35

Cumulative Sum Graph (CUSUM)

Question 36

-It is used to compare results obtained on a high and low control serum from different laboratories.

Answer 36

Youden/ Twin Plot

Question 37

Most widely used system in clinical laboratory.

Answer 37

Shewhart Levey – Jennings Chart

Question 38

-Formed by control values that either increase of decrease for six consecutive days.
Main Cause: Deterioration of reagents

Answer 38

Trend

Question 39

-It is formed by the control values that distribute themselves on one side or either side of the mean for six consecutive days.
Shift in the reference range is due to transient instrument differences.
Main Cause: Improper Calibration of Instruments

Answer 39

Shift

Question 40

These are control values that are far from the main set of values’
They are highly deviating values
Caused by random or systematic errors

Answer 40

Outliers