Post by Rashi Parashar

Module 2nd:-Hands-on with Molecular Biology – Bacterial DNA Isolation 🧬 ​Excited to kickstart my practical journey in Cell & Molecular Biology! Today’s focus was on Bacterial DNA Isolation—a fundamental yet crucial technique in biotechnology. 🧫 ​Here is a quick look at the workflow and the fascinating science behind the chemicals used to unlock and preserve genomic DNA: ​⚙️ The Workflow ​Cell Harvesting: Centrifuged the broth culture to isolate the bacterial pellet. ​Lysis & Incubation: Treated the pellet with lysis buffer and incubated at 37°C to break open the cell walls. ​Phase Separation: Used a Chloroform : Isoamyl Alcohol (24:1) mixture to separate cell debris. Centrifugation successfully generated three distinct layers: ​Upper Layer: Aqueous (contains DNA) ​Middle Layer: Dense white milky interface (denatured proteins) ​Lower Layer: Organic phase ​Precipitation: Added Isopropanol (1:1 ratio) and incubated at 4°C to precipitate the DNA, followed by pelleting, air-drying, and storage. ​🧪 The Chemistry Behind the Protocol ​Understanding why each reagent is used is key to mastering molecular workflows: ​TE Buffer: Tris maintains a stable pH, while EDTA chelates metal ions to inhibit DNase enzymes, preventing DNA degradation. ​SDS (Sodium Dodecyl Sulfate): Denatures proteins and disrupts cell membranes to release genomic DNA. ​Phenol : Chloroform : Isoamyl Alcohol: Phenol/Chloroform denatures and separates proteins from nucleic acids, while Isoamyl Alcohol prevents foaming during the process. ​Isopropanol / Ethanol: Lowers the dielectric constant of the solution, allowing DNA to precipitate out so it can be collected. ​Nuclease-free Water / TE Buffer: Used for final elution to dissolve and safely store the purified DNA long-term. ​Looking forward to the next steps: DNA Quantification and Gel Electrophoresis to check the yield and purity! 📊🎯 ​#MolecularBiology #Biotechnology #DNAIsolation #LabLife #Research #Genetics #ScienceCommunication