To remove smaller solutes, such as endotoxins, which filter should be used?

Ultrafilters are specifically designed to remove smaller solutes, including endotoxins, from a solution. These filters utilize a semi-permeable membrane with very small pores, typically ranging from 1 nanometer to 0.1 microns in size, making them effective for separating particles based on size. This capability is particularly critical in medical and laboratory settings, where the removal of endotoxins is mandatory to ensure safety and sterility.

In contrast, other types of filters have different primary functions. Wound filaments are usually utilized for larger particulate matter and are not effective for removing microscopic substances such as endotoxins. Membrane cartridges can vary in their filtration properties but typically focus on medium-sized particles and may not be as efficient in retaining such small solutes. Carbon filters are primarily used for adsorbing impurities and chemicals, such as chlorine or organic compounds, rather than for precise filtration of endotoxins or similar small solutes.

Thus, ultrafilters stand out as the appropriate choice for targeting very small molecules and ensuring the removal of potential contaminants like endotoxins.