Conductometry is a significant analytical technique used in various fields, including pharmaceutical analysis, to measure the electrical conductivity of a solution.
This measurement is indicative of the presence and concentration of ions in the solution, which is essential for understanding many aspects of a solution's composition and properties.
Here's an introduction to conductometry, focusing on its application in pharmaceutical analysis:
Fundamentals of Conductometry:
1) Electrical Conductivity:
It's the ability of a substance to conduct electric current, which in solutions, is due to the movement of ions.
Conductivity is inversely related to resistance.
2) Conductance (G):
The ease with which the electric current flows.
It's the reciprocal of resistance.
3) Cell Constant (k):
It's specific to the conductometric cell used and is a factor of the electrode's size and distance apart.
Measurement:
1. Conductometric Cell:
A typical setup involves a pair of electrodes immersed in the solution whose conductivity is to be measured.
2. AC Current:
Alternating current is used to prevent electrolysis at the electrodes, which could affect the measurements.
Advantages in Pharmaceutical Analysis:
Sensitivity: Conductometry is sensitive to changes in ionic concentration, making it useful for detecting even small amounts of ionic impurities.
Non-Destructive: It doesn't alter the sample, allowing for further analysis if needed.
Rapid and Easy: Conductometric measurements are typically quick and don't require complex procedures.
Applications of Conductometry
1. Pharmaceutical analysis:
Determines the concentration of active ingredients, impurities, and degradation products in drug formulations.
Useful for monitoring solid dosage dissolution and analyzing electrolytes in intravenous solutions.
2. Water quality monitoring:
Measures total dissolved solids (TDS), water hardness, salinity, and concentrations of anions and cations in water samples.
3. Environmental analysis:
Assesses pollutant concentrations (e.g., heavy metals, organic compounds) in air, water, and soil.
Used to monitor chemical reactions in industrial processes. Top of Form Bottom of Form