Comparison of sample introduction techniques with a continuously heated graphite-furnace atomizer for...

Area of Science:

• Analytical Chemistry
• Spectroscopy
• Materials Science

Background:

• Graphite furnaces are crucial for high-temperature chemical analysis.
• Optimizing sample introduction is key to improving sensitivity and reducing interferences in atomic absorption spectroscopy.
• Ensuring furnace longevity requires specific preparation techniques, such as pyrolytic coating.

Purpose of the Study:

• To describe a novel graphite furnace system capable of continuous operation or high-temperature ramping.
• To investigate and compare two distinct sample introduction methods for atomic absorption spectroscopy.
• To evaluate the performance of the graphite furnace in terms of operational ease, precision, sensitivity, and interference mitigation.

Main Methods:

• Development and characterization of a graphite furnace operable up to 2100°C continuously or 3100°C via temperature ramp.
• Implementation of pyrolytic carbon coating for enhanced furnace tube lifespan.
• Investigation of two sample introduction techniques: continuous nebulization with desolvation and aerosol deposition prior to ramping.

Main Results:

• Pyrolytic coating of graphite tubes is essential for achieving satisfactory operational lifetime.
• Continuous nebulization provides good precision (RSD = 1-1.3%) and ease of operation but exhibits significant interferences.
• Aerosol deposition offers higher sensitivity, good precision (RSD = 1.8-2.3%), and combines benefits of conventional furnace atomic absorption with simpler operation.

Conclusions:

• The developed graphite furnace is suitable for high-temperature atomic absorption spectroscopy.
• Aerosol deposition is a superior sample introduction method for achieving higher sensitivity and minimizing interferences.
• The findings contribute to advancements in analytical techniques for elemental analysis using graphite furnace atomic absorption spectroscopy.