Preparing silver nanoclusters (AgNCs) typically involves reducing silver salts in the presence of stabilizing agents (short DNA oligos with single-stranded cytosine regions). Start by dissolving silver nitrate (AgNO₃) in water, then add a reducing agent (e.g., sodium borohydride) in presence of DNA oligos. Allow the reaction to proceed under controlled conditions until the desired fluorescence or size is achieved. Learn more from our study on the silver nanoclusters and their antibacterial properties: https://www.mdpi.com/1420-3049/26/13/4045

Purifying RNA using urea-PAGE (denaturing polyacrylamide gel electrophoresis) involves separation of RNAs by size. First, prepare a denaturing gel with urea and TBE buffer. Mix the RNA sample with a loading buffer containing urea and heat it to denature secondary structures. Load the sample onto the gel and run electrophoresis under a constant voltage. Visualize the RNA using UV shadowing. Excise the desired RNA band, crush or soak it in an extraction buffer, and recover the purified RNA by ethanol precipitation!

To load and run an agarose gel, first prepare the gel by dissolving agarose in a buffer (e.g., TBE), heating until fully dissolved, then pouring it into a gel tray with a comb to form wells. Once solidified, place the gel in an electrophoresis chamber filled with running buffer. Mix the DNA or RNA samples with a loading dye, then carefully pipette them into the wells. Run the gel at an appropriate voltage until the bands separate. Visualize the nucleic acids using a gel imaging system after staining with ethidium bromide or a safer alternative like SYBR Safe.

This video outlines the preparation of an Ethidium Bromide Agarose gel for use in DNA visualization

Purifying PCR products removes unwanted components such as primers, dNTPs, enzymes, and buffer salts that may interfere with downstream applications. Clean PCR products are essential for accurate sequencing, cloning, qPCR, or in vitro transcription. Follow the steps from this video to get the pure products!

To run a PCR, prepare a reaction mix containing DNA template, primers, dNTPs, a Taq polymerase, and a reaction buffer. Set the PCR program with the following steps: denaturation (~95°C, 30 sec), annealing (50–65°C, 30 sec, depending on primer Tm), and extension (72°C, 30 sec–1 min, depending on amplicon length). Repeat for 25–35 cycles, then perform a final extension at 72°C. After completion, store the PCR products at 4°C or analyze using agarose gel electrophoresis.

To use a mechanical pipette, first select the appropriate volume and attach a sterile tip. Press the plunger to the first stop, then immerse the tip in the solution and slowly release the plunger to draw up the sample. Transfer the liquid to the desired container and press the plunger to the second stop to fully dispense. Eject the tip using the tip ejector button. Always hold the pipette vertically, change tips between samples, and calibrate regularly for accuracy.