Agarose Powder

Agarose is a polysaccharide, derived from seaweed, what we commonly find in molecular biology labs. Agarose made up of a chain of β-D-galactopyranosyl units, link via (1,3) bonds, as well as (1,4) bonds to 3,6-anhydro-α-D-galactopyranosyl units. The double helical structure, formed by these chains interaction, let agarose create a gel matrix. The helical structure creates a porous network of agarose chains that can trap water molecules and solute, forming a gel when the agarose solution cools and solidifies.
Agarose gels utilized to separate and visualize DNA and RNA fragments of various sizes, mainly come from PCR, restriction enzyme digestion or RNA/DNA extraction product. Agarose is quite popular choice for this task because it forms a stable gel matrix when mix up with buffer and heated, which let for separation of DNA fragments by sizes as they migrate through the gel under electric field. The percentage of agarose used in the gel decide the pore size, and thus, the size of DNA fragments that get resolved. Agarose gels with higher concentrations result in smaller pores and lower concentrations end up in larger pores.