Chemistry:Microanalysis

Microanalysis is the chemical identification and quantitative analysis of very small amounts of chemical substances (generally less than 10 mg or 1 ml) or very small surfaces of material (generally less than 1 cm²). One of the pioneers in the microanalysis of chemical elements was the Austrian Nobel Prize winner Fritz Pregl.

Methods

The most known methods used in microanalysis include:

• Most of the spectroscopy methods: ultraviolet–visible spectroscopy, infrared spectroscopy, nuclear magnetic resonance, X-ray fluorescence, Energy-dispersive X-ray spectroscopy, Wavelength-dispersive X-ray spectroscopy, and mass spectrometry
• Most of the chromatography methods : high-performance liquid chromatography, Gel permeation chromatography;
• Some thermal analysis methods: differential scanning calorimetry, thermogravimetric analysis;
• Electrophoresis;
• Field flow fractionation;
• X-ray diffraction;
• Combustion analysis.

Advantages

Compared to normal analyses methods, microanalysis:

• Can resolve fine-scale variations in chemical elements.
• Can be used to identify the presence and distribution of different phases in materials.
• Requires less sample material and therefore can provide information on microscopic objects.

Disadvantages

• Handling of small quantities is not always simple.
• Higher accuracy of weighing is necessary (e.g. use of accurate balance).
• Sample surface preparation can have a major impact on measurement results.