Agarosegeeli

Agarose gel, also known as agarosegeeli in some languages, is a porous matrix used in gel electrophoresis to separate nucleic acids by size. It is prepared by dissolving agarose powder in a suitable buffer, heating to dissolve, and then casting the solution in a mold with a comb to form wells. After it solidifies, a running buffer is added and samples are loaded for electrophoresis.

Agarose is a natural polysaccharide derived from red seaweed. The pore size of the gel depends on the agarose concentration, typically ranging from about 0.5% to 3%. Lower concentrations resolve larger DNA fragments, while higher concentrations favor separation of smaller fragments. In an electric field, DNA and RNA migrate toward the positive electrode, with smaller fragments moving faster through the gel matrix.

Common applications include sizing and analyzing PCR products, checking restriction enzyme digests, verifying plasmid constructs, and assessing RNA or DNA fragment length distributions in research and diagnostic settings. Agarose gels are prized for ease of use, low cost, and scalability, though they offer lower resolution for very small fragments compared with other gel types such as polyacrylamide gels.

Buffers such as TAE (Tris-acetate-EDTA) and TBE (Tris-borate-EDTA) are used with agarose gels. DNA is typically stained with intercalating dyes, including ethidium bromide or safer alternatives like SYBR Safe or GelRed, and visualized under UV or blue-light transilluminators. Limitations include limited resolution for small fragments and potential artifacts from running conditions.