Introduction to Agarose Gel Electrophoresis
" Agarose Gel Electrophoresis: Visualizing DNA in Motion" # Introduction Agarose gel electrophoresis is the core analytical method used to separate, identify, and analyze DNA fragments based on size. From verifying plasmid extractions to confirming PCR results or restriction digests, this method serves as the microscope of molecular genetics , letting scientists literally see DNA migrate under the influence of an electric field. Simple, elegant, and incredibly powerful — it’s one of the first experiments every biotechnologist learns, and one of the last they ever stop using. # Scientific Principle DNA is a negatively charged polymer due to its phosphate backbone. When placed in an electric field , it migrates toward the positive electrode (anode) . An agarose gel acts as a molecular sieve, separating DNA fragments according to their size : Smaller fragments move faster and farther. Larger fragments move slower through the gel matrix. This migration ...