Analytical Methods Flashcards
measurement of light transmitted by a solution
SPECTROPHOTOMETER
Light or Radianr Source of Spectrophotometer
POLYCHROMATIC LIGHT
most commonly used light source
TUNGSTEN IODIDE LAMP
As the lamp envelope darkens with age, the instrument readout will not rise above the 90% T, instead 100% T. What should the MTOD do?
Replace the Sourcr Lamp
Light Source used in AAS
Hollow Cathode Lamp
TRUE or FALSE
The transmittance should be 100% at all times
TRUE
What are the components of a spectrophotometer?
Light Source
Entrance Slit
Monochromator
Exit Slit
Sample Cuvette
Photodetector
Readout Device
What is the most common cause of Loss of Linearity?
STRAY LIGHT
Most commin cause of stray light?
Second Order Spectra:
- Deteriorated Optics
- Light Dispersed by Darkened Envelope
- Extraneous Room Light
What are the type of filter is best in measuring stray light?
Sharp Cut Off Filters
What is used in verifying absorbance accuracy and linearity?
Neutral Density Filters and Dichromate Solution
Isolates specific wavelength of light.
Monochromator
Most commonly used monochromator
Diffraction Gratings
Short wavelengths are refracted more than long wavelengths, composed of sodium chloride, and considered to produce the purest light
Prism
Half band width of a monochromator is defined by the range of wavelength passed at ______ maximum transmittance.
50%
This is used to check the wavelength accuracy
Didymium Holmium Oxide Filter
It controls the bandpass or bandwidth, control the light reaching the sample cuvette
Exit Slit
If the wavelength is 540 nm and the bandpass allows 10 nm, what is the wavelength range?
535 nm to 545 nm
It is also called absorption cell, analyticsl cell or sample cell which holds the sample/solution.
Cuvette
Most commonly used type of cuvette
Alumina Silica
Unknown substances is DIRECTLY PROPORTIONAL to the absorbed light, and INVERSELY PROPORTIONAL to the TRANSMITTED LIGHT
Beer’s Law
Beer’s Law Absorbance Formula
2 - log % T
Most common type of photomultiplier and the most sensitive one
Photomultiplier Tube
simplest detector and do not require external voltage source
Barrier Layer Cell
Photocell
Photovoltaic Cell
simplest type of spectrophotometer and it measures one at a time
Single Beam Spectrophotometer
permit automatic correction of sample and uses two photodetectors
Double Beam Spectrophotometer
Double Beam Spectrophotometer that uses two photodetectors
In Space
A solution consisting of all the components of a reacting EXCEPT THE ANALYTE.
Blank
A blank contains seruk but without reagent to complete the assay
Blanking Technique
Contains the same reagent for the assay and corrects for absorbance caused by the color of the reagents.
Reagent Blank
Sample blank is used to subtract the intrinsic absorbance of the sample usually caused by hemolysis, icterus, turbidity, or drug interference, it is performed by substituting the ______ for reagent.
SALINE
In reflectance photometry, 100% reflectance is set with an ________ film called the white reference.
OPAQUE
In Automated Reagent Strip Reader, concentration of analyte/sample is ____________ to reflectance (light reflected).
INVERSELY PROPORTIONAL
Minimizes error caused by source lamp
Fluctuations
What principle is used in Bilirubinometer and Automated Reagent Strip Reader?
Reflectometry or Reflectance Photometry
What is the hottest flame color?
BLUE
Measures the light emitted by a single aton burned in a flame.
Flame Emission Photometry
In FES, Sodium emits ____color.
Yellow
In FES, Potassium emits ____color.
Violet/Purple
In FES, Lithium/Rubidium emits ____color.
Red
In FES, Magnesium/Copper emits ____color.
Blue
Type of spectrophotometer that uses an atomizer
Atomic Absorption Spectrophotometer
Element is not excited, but merely dissociated from its chemical bond and place un an ionized, unexcited, ground state
AAS
AAS Light Source
Hollow Cathode Lamp
Used by AAS to convert ions to atoms,
Atomizer/Graphite Furnace
Most common burner used in AAS
Premix Long Path Burner
Disadvantages of AAS
Flame Inefficiency and Matrix Interference
Used by AAS to increase sensitivity for atomic emission
Inductively Coupled Plasma
Uses two monochromators
Fluorometry
In Fluorometry, this controls the light intensity.
Attenuator
In Fluorometry, what is the purpose of primary monochromator?
isolates the wavelength for excitation
In Fluorometry, what is the purpose of secondary monochromator?
isolates the wavelength emitted by the fluorochrome
Light source used in fluorometry
Mercury Arc Lamp
1000x more sensitive than spectrophotometer
Fluorometry
Most common problem encountered in Fluorometry?
QUENCHING (Diminishing Light)
Presence of Anti HLA B21
Ankylosing Spondylitis
Emission of light is created from a chemical or electrochemical reaction. DOES NOT require excitation and monochromator.
Chemiluminescence
Photodetector used by Chemiluminescence:
Photomultiplier Tube (Luminometer)
Measures light blocked (reduction of light) by a particle and is dependent on CONCENTRATION and PARTICLE SIZE
TURBIDIMETRY
More sensitive than turbidimetry and determines the SCATTERED LIGHT.
Nephelometry
Dependent on WAVELENGTH and PARTICLE SIZE
Nephelometry
meaning of L.A.S.E.R.
Light Amplification by Stimulated Emission of Radiation
low divergence
LASER
Separation of soluble components in a solution by specific differences
CHROMATOGRAPHY
Screening Test for Drugs of Abuse
Thin Layer Chromatography
Chromatography used for sugars and amino acids
Paper Chromatography
Gold Standard for Drug Test (Drugs of Abuse)
GCMS
According to Dangerous Drugs Board, the test shall be challenged within _____ days AFTER receipt of the result through GCMS
15 DAYS
If the sample for Drugs of Abuse is not challenged within 15 days, then it shall be _____.
DISCARDED
In Chromatography, a noisy baseline indicates that the carrier gas is ______.
CONTAMINATED.
Method that detects 20 inborn errors if metabolism
MS/MS
In MS/MS, what is the purpose of VACUUM?
It is needed to PREVENT COLLISION between fragments.
Mobile phase used in Gas Chromatography.
Helium
Most widely used chromatography
HPLC
the primary means of solutes separation in HPLC using a C18 column
PARTITIONING
What is the component used in GC-MS, but is not used in LC-MS?
ELECTRON SOURCE
Detector used in HPLC
Glassy Carbon Electrode
Unknown Sample + Known Sample with indicator
Volumetric (Titrimetric)
Principle of Schales and Schales (Titration of Chloride)
Volumetric/Titrimetric
What are the osmotic particles?
Sodium, Glucose, and BUN
Osmolality formula
2 (Na) + Glucose/20 + BUN/3
What are the colligative properties?
Boiling Point
Osmotic Pressure
Freezing Point
Vapor Pressure
Osmometer Reference Solution
Sodium Chloride
What colligative property is commonly measured/used method?
Freezing Point
Colligative properties that has INVERSE relationship with osmolality.
FaVor
Freezing Point
Vapor Pressure
Component of freezing point osmometer that measures the sample temperature
THERMISTOR
Principle employed in a vapor pressure osmometer
Seebeck Effect
Each osmole, freezing point is lowered by _______.
-1.86%
Formula for Osmolal Gap
Measured Osmolality - Calculated Osmolality
Freezing Point Osmometer is sensitive to _______ while vapor pressure osmometer is not.
ETHANOL
What test is needed to support Na, Glucosec and BUN patient testing, without the need to recollect?
OSMOLAL GAP
Ideal for separation of Tricyclic Antidepressants and their metabolites
HPLC
potential difference between an indicator electrode and a reference electrode is measured and FOLLOWS NERNST EQUATION
POTENTIOMETRY
The reference potential of Silver-Silver Chloride electrode in Potentiometry is determined by the concentration if the __________ filling solution.
POTASSIUM
Principle of Severinghaus Electrode
Potentiometry
What is the principle of ISE?
Potentiometry
In ISE, the membrane composition used to detect potassium is _____.
ANTIBIOTIC VALINOMYCIN GEL
Persistent noise in ISE
BLOCKED JUNCTION AT SALT BRIDGES
It follows Faraday’s Law and is the measurement of the amount of electricity (in coulombs) at a fixed potential
The number of equivalent weights of a reactant oxidized or reduced is DP to the quantity of electricity.
COULOMETRY
Coulometry interfence
Bromide
Electrochemistry technique where the end point is measured by Amperometry
Coulometry
Principle of Chloride Coulometer
Coulometry
measures the amount of current produced through the oxidation or reduction if the substance to be measured at an electrode
Amperometry
It follows the Ilkovic Equation
Polarography
Principle of Clark Electrode for pO2
Amperometry
Anodic Stripping Voltammetry is used in what analysis?
LEAD ANALYSIS
It is also known as the decentralized test, bedside test, and near-patient testing
POCT
In types of ISE, which is NOT AFFECTED by Hypernatremia and Hyperlipidemia?
DIRECT ISE
determines concentrations of metabolites with very small sizes
METABOLOMICS
An immunosuppresant drug that has high clinical value used in PAPER SPRAY IONIZATION
TACROLIMUS
Number of vibrations of wave motion per second
FREQUENCY
Distance between two successive peaks and is expressed in nanometer (nm)
WAVELENGTH
- Measurement of light intensity using specific wavelength
- Measurement of light intensity in a narrower wavelength
- PHOTOMETRIC MEASUREMENT
- SPECTROPHOTOMETRIC MEASUREMENT
TRUE or FALSE
the narrower the bandpass, the greater the resolution
TRUE