ANALYTICAL METHODS [ELECTROCHEMISTRY] Flashcards
This is the measurement of current or voltage generated by the activity of a specific ion.
Electrochemistry
What are measured in electrochemistry?
- Blood Gases
- pH
- Electrolytes
- Glucose
- Urea
- Ica
- Chloride
This technique is the measurement of electrical potential due to the activity of free ions.
Potentiometry
What equation does potentiometry follow?
Nernst Equation
What are the reference electrodes in potentiometry?
Calomel and Silver-Silver Chloride
What are the uses of potentiometry?
pH and pCO2 tests
This is an electrochemical transducer capable of responding to one given ion.
Very sensitive and selective for the ion it measures.
Ion selectivity depends on the membrane/barrier composition used.
Ion Selective Electrode (ISE)
What are the ISE membranes used?
- Glass Aluminum Silicate
- Valinomycin Gel
- Organic Liquid Membrane
- Gas and Enzyme Electrodes
What are the two types of ISE?
Direct and Indirect ISE
This technique measures the amount of electricity at a fixed potential.
Follows Faraday’s law.
Used for the Chloride Test.
Interferences are Bromide, Cyanide, and Cysteine.
Coulometry
This technique is the measurement of the current floww produced by an oxidation reaction.
Examples are: pO2, glucose, chloride, and peroxidase determination.
Amperometry
This is the measurement of differences of current at a constant voltage.
This is specific for pO2, and can also be used for glucose.
Follows the Ilkovic Equation.
Polarography
This technique is the measurement of the current after which a potential is applied to an electrochemical cell.
This allwo samples to be preconcentrated, thus making use of minimal analyte.
Voltammetry
This is used for lead and iron testing.
Anodic Stripping Voltammetry
