Specimen holder to critical-point dry microorganisms for scanning electron microscopy

Area of Science:

• Microbiology
• Microscopy techniques

Background:

• Scanning electron microscopy (SEM) requires specific sample preparation methods.
• Critical-point drying (CPD) is a common technique for preserving cellular structures in SEM.

Purpose of the Study:

• To introduce a novel specimen holder for critical-point drying of microorganisms.
• To evaluate the efficiency and effectiveness of the new holder in SEM sample preparation.

Main Methods:

• Development of a new specimen holder designed for processing multiple microbial samples.
• Utilizing polycarbonate membrane filters to separate individual samples within the holder.
• Employing solvent dehydration followed by critical-point drying with carbon dioxide.

Main Results:

• The new specimen holder allows for rapid and effective critical-point drying of up to eight different microbial samples.
• Successful processing of various microorganisms including yeasts, molds, bacteria, and actinomycetes.
• Demonstrated prevention of sample loss and cross-contamination during the drying process.

Conclusions:

• The described specimen holder significantly improves the critical-point drying process for microbial SEM.
• This method offers a reliable and efficient approach for preparing diverse microorganisms for high-resolution imaging.