Schaffer's solution, also known as glutaraldehyde-formol solution, is a fixing solution used in histology and electron microscopy. It consists of a mixture of glutaraldehyde and formaldehyde dissolved in a suitable buffer, such as a phosphate buffer.

Glutaraldehyde is a bifunctional aldehyde that can form covalent cross-links between proteins and other biological macromolecules in cells and tissues. Formaldehyde is a single-functional aldehyde that reacts primarily with amino groups of proteins, thus also helping to stabilize cell structures.

The combination of glutaraldehyde and formaldehyde in Schaffer's solution provides improved fixation of cell structures compared to solutions containing only one of the two aldehydes. Schaffer solution is particularly useful for fixing cellular structures to be studied in electron microscopy, as it provides good preservation of fine cellular details.

Fixation with Schaffer solution should be performed at room temperature or in a refrigerator, depending on the specific requirements of the experiment. The fixing solution is always freshly prepared before shipment!