The supplies you need depend entirely on which type of gel you’re making. The most common reasons people search this question are for laboratory agarose gels (used in biology to separate DNA), hand sanitizer gels, or cosmetic/personal care gels. Each requires a different set of materials, so here’s a breakdown of the major types.
Agarose Gel for Electrophoresis
Agarose gel electrophoresis is one of the most common lab techniques in molecular biology, used to sort DNA or RNA fragments by size. A standard 1% gel uses 1 gram of agarose powder dissolved in 100 mL of buffer solution. The supplies fall into two categories: consumables you use up each time and equipment you reuse.
Consumables
- Agarose powder: A purified seaweed-derived powder that forms the gel matrix when heated and cooled. Molecular biology grade agarose runs around $290 to $400 for 100 grams from major suppliers like Fisher Scientific, though educational-grade options cost less.
- Buffer solution: You need either TAE or TBE buffer. TAE contains Tris base, acetic acid, and EDTA (a chemical that protects DNA from degradation). TBE swaps in boric acid for the acetic acid. Most labs buy these as concentrated stock solutions and dilute them with distilled water before use.
- Staining dye: To actually see the DNA in your gel, you need a fluorescent dye. Ethidium bromide was the standard for decades but is toxic and mutagenic. Safer alternatives like GelRed and GelGreen are now preferred, offering equal or better sensitivity without the hazard.
- Loading dye and DNA ladder: Loading dye adds color and weight to your samples so they sink into the gel wells. A DNA ladder is a pre-made mix of known fragment sizes that runs alongside your samples for comparison.
Equipment
- Gel box (electrophoresis chamber): A plastic tank that holds the gel submerged in buffer, with electrodes at each end to create an electric field.
- Casting tray and well combs: The tray molds the gel into shape. Combs sit in the liquid gel and create small wells (pockets) where you load your DNA samples.
- Power supply: Provides the voltage that drives DNA through the gel. Standard DNA work requires 50 to 150 volts. Protein gels need higher voltages, typically 200 to 300 volts.
- Microwave or hot plate: Used to dissolve the agarose powder in buffer. The mixture needs to reach a full boil, then cool to around 50 to 60°C before pouring.
- UV or blue light source: Activates the fluorescent dye so you can photograph the DNA bands. If using UV light, you’ll also need UV-blocking eye protection or a face shield.
- Heat-resistant gloves: Molten agarose can cause burns. Insulated gloves protect your hands when handling the hot flask, and you should always point the opening away from yourself since superheated liquid can froth unexpectedly.
Hand Sanitizer Gel
Making a gel-based hand sanitizer requires surprisingly few ingredients. The WHO’s recommended formulation calls for ethanol at 80% concentration (or isopropyl alcohol at 75%), glycerol at 1.45%, and hydrogen peroxide at 0.125%. The hydrogen peroxide isn’t there to kill germs on your hands. It deactivates any bacterial spores that might contaminate the batch during production. Glycerol acts as a moisturizer to prevent skin drying.
The WHO formulation is technically a liquid, not a gel. To turn it into a gel, you need a thickening agent. Carbomer 940 is the most widely used polymer thickener for this purpose. It comes as a white powder that swells into a gel when you neutralize it with a base, typically triethanolamine (TEA) or sodium hydroxide. The ratio is roughly 1.5 parts TEA to 1 part carbomer. TEA works well in formulations containing up to 50% alcohol. You’ll also need distilled or sterile water, a digital scale, mixing containers, and a stirring tool.
Polyacrylamide Gels for Protein Work
If you’re separating proteins rather than DNA, the standard tool is a polyacrylamide gel, commonly called SDS-PAGE. The chemistry is different from agarose. Instead of melting and cooling a powder, you mix liquid acrylamide with a crosslinker, then trigger a chemical reaction that hardens the mixture into a solid gel.
The key supplies are an acrylamide/bis-acrylamide solution, a buffer system (usually Tris-based), ammonium persulfate (APS), and TEMED. APS generates free radicals that start the polymerization reaction, and TEMED accelerates the process. The gel solution needs to stay at a pH between 8 and 9 for these two chemicals to work properly. You also need glass plates and spacers to cast the gel vertically, plus a comb for forming sample wells. A vertical electrophoresis chamber and power supply capable of constant current mode round out the equipment list. Acrylamide is a neurotoxin in its unpolymerized form, so nitrile gloves and careful handling are essential.
Medical Hydrogels
Hydrogels used in wound dressings and medical applications are built from water-absorbing polymers. The two most common synthetic options are polyvinyl alcohol (PVA) and polyethylene glycol (PEG). PVA is the more established choice, known for its ability to maintain a moist wound environment and resist protein buildup. PEG is FDA-approved for biocompatibility and is transparent, nontoxic, and eventually absorbed by the body.
Natural polymer alternatives include collagen, chitosan (derived from crustacean shells), silk fibroin, and alginate (from seaweed). These tend to trigger less inflammation and break down naturally, but they have weaker mechanical strength and can vary between batches. Making medical hydrogels at home isn’t practical or safe, as they require controlled crosslinking conditions and sterility, but understanding the base materials helps if you’re researching the topic for academic or product development purposes.
Choosing the Right Gel Type
For a school or university lab course, agarose gel electrophoresis is almost certainly what you need. A basic setup with a gel box, power supply, casting tray, combs, agarose, buffer, and staining dye covers the essentials. Budget around $300 to $500 for the reusable equipment if buying new, plus ongoing consumable costs.
For DIY hand sanitizer, the ingredient list is short but sourcing high-concentration alcohol and carbomer thickener can be tricky outside of chemical supply companies. If you’re working on a cosmetics or personal care formulation, carbomer 940 with a TEA neutralizer is the standard thickening system and the easiest starting point for creating a clear, stable gel texture.