Techniques in Molecular Biology

Extract DNA by disrupting cell walls, using young leaf tissue and liquid nitrogen to grind. Apply extraction buffer with detergents and EDTA; then precipitate DNA with cold ethanol and centrifuge.

Explore how electrophoresis moves charged particles in a gel under an electric field. Compare gel electrophoresis with polyacrylamide gel electrophoresis and learn its DNA, RNA, and protein analysis applications.

Quantify dna concentration and assess purity using a spectrophotometer by measuring absorbance at 260 and 280 nm, with a260/a280 ratio near 1.8; apply in forensics, paternity testing, and diagnostics.

Use agarose gel electrophoresis to separate nucleic acids by size and charge, adjust gel concentration for resolution, and visualize DNA under UV to estimate fragment sizes.

Explore how SDS-PAGE denatures proteins to carry negative charge and separates them by size in polyacrylamide gels, enabling molecular weight estimation and purity assessment.

Explore how complementary DNA or RNA strands hybridize to reveal specific targets using primers and probes, while blotting techniques (Southern, Northern, and Western blotting) transfer and reveal them.

Learn how Southern blotting detects specific DNA sequences within a restriction-digested smear by separating fragments via electrophoresis, transferring to a membrane, and probing with labeled DNA.

Explore northern blotting to detect RNA and measure gene expression by gel separation, membrane transfer, probe hybridization, and X-ray visualization.

Detect proteins from a mixture by western blotting, including isolation, gel electrophoresis, membrane transfer, and antibody-based visualization using primary and secondary antibodies.

Master polymerase chain reaction (PCR) and its thermal cycling to amplify DNA, using primers, nucleotides, and a thermostable DNA polymerase, with confirmation by agarose gel electrophoresis.

Design primers 18–30 nucleotides long with 50–60% GC content and unique sequences to ensure specific amplification; verify PCR products by electrophoresis and note applications like genetic fingerprinting and prenatal testing.

DNA sequencing determines the sequence of nucleotide bases in DNA using a sequencing primer, terminator bases, fluorescently labeled bases detected by a laser, and DNA polymerase to extend the strand.

Learn how capillary electrophoresis reads terminator-labeled bases to convert color sequences into DNA sequences, and explore sequencing applications from genomes and disease genes to paternity, agriculture, evolutionary biology, and metagenomics.

Explore key molecular biology components and techniques, including buffers, liquid nitrogen disruption, DNA and RNA extraction, ethanol and isopropanol precipitation, gel electrophoresis, blotting methods, and probes.