Analysis of Protein Aggregates Size and Morphology by Electron Microscopy (CAT#: STEM-B-0299-CJ)

The electron microscope uses a beam of electrons and their wave-like characteristics to magnify an object's image.it can be used to analyze structures which cannot otherwise be seen. The resolution of electron microscopy images is in the range of up to 0.2 nm, which is 1000x more detailed than light microscopy.

Biopharmaceutica

1. Isolate and clean the specimen. This may involve cross-sectioning, excising, or otherwise reducing the size of the specimen so that it will fit in the SEM, and removing any contamination that could damage the microscope (oil, water, other environmental contamination).
2. Determine the area of interest for analysis in the SEM, and mark the specimen so that this area can be easily located when the specimen is in the SEM. Here, light (optical) microscopy can be useful as a first pass analysis.
3. If needed, sputter coat the specimen with a thin layer of metal. This step is needed if the specimen is electrically insulating to prevent charging, which will introduce artifacts in the image.
4. Place the sample into the SEM, which will normally involve: (Mounting the specimen on the sample stage; Bringing the specimen chamber of the SEM up to atmospheric pressure; Loading the sample holder into the SEM).
Pumping the specimen chamber to the required vacuum
5. Move the sample into the analysis position, and using low magnification, find the areas of interest.
6. At higher magnification, optimize the lens settings (magnification, beam energy, beam size, focus).
7. Collect images at a variety of magnification, using both secondary and backscattered electrons.

• Sample: Proteins
• Equipment: Electron Microscopy

• The formation of aggregates in your biopharmaceutical product can have a negative effect on safety, efficacy and function. Regulatory authorities expect that orthogonal characterization techniques are used to fully understand the aggregation profile of any molecule.
• Measurable range: nm–mm