Laboratory Glass and Reagent Bottles

Narrow-neck reagent bottles are designed for pouring liquids cleanly and minimising evaporation during storage. Wide-neck bottles allow easier filling with viscous liquids, powders, or bulk samples, and are simpler to clean with a bottle brush. For most liquid reagents, a narrow-neck bottle with a ground-glass stopper or screw cap is the standard choice.

Ground-glass stoppers provide an excellent solvent-resistant seal and are the preferred closure for volatile solvents and strong acids. However, they can seize with alkaline solutions or if left assembled for long periods. Screw caps with PTFE-lined lids are more practical for everyday use — they cannot seize, are interchangeable, and still provide a good seal for most reagents. For vacuum or high-pressure applications, always verify the closure is rated for the pressure involved.

Use clear glass when you need to visually monitor the contents, when colour change indicates a reaction, or when light sensitivity is not a concern. Use amber glass for photosensitive reagents including silver salts, iodine-based solutions, hydrogen peroxide, many organic dyes, and biological staining solutions. When in doubt, amber glass is the safer choice, as it protects against both UV and visible light degradation.

Match the bottle volume to the quantity you regularly store or use. Choose a size that leaves 10 to 15 percent headspace to allow for thermal expansion and to prevent the reagent from contacting the closure when the bottle is inverted. Storing small amounts in large bottles accelerates oxidation and contamination due to the excess air volume in the headspace; it is better to use a bottle that is mostly full.

A reagent bottle is a narrow-neck storage bottle designed for long-term chemical storage, typically fitted with a ground-glass stopper or PTFE-lined screw cap. It is used to store prepared solutions, stock chemicals, and solvents. A sample bottle is usually a wide-neck container designed for collecting, transporting, and storing physical or biological samples such as soil, water, or tissue. Wide-neck sample bottles allow easier filling and are simpler to clean between uses.

Amber glass contains iron oxide and other additives that absorb UV and visible light wavelengths below approximately 500 nm. Many chemical compounds degrade when exposed to light — a process called photodegradation. Silver nitrate, hydrogen peroxide, iodine-based solutions, many pharmaceutical compounds, and sensitive biological stains all require amber glass storage to maintain their potency. If your reagent label says "store in the dark" or "protect from light," use an amber glass bottle.

Yes, provided the bottles are made from borosilicate glass and are correctly prepared. Ensure the cap or stopper is loosely fitted — not tightly sealed — so that pressure inside the bottle can equalise with the autoclave chamber. A sealed bottle can shatter during autoclaving or on pressure release. Allow the autoclave and the bottles to cool to at least 80°C before removing them. Do not autoclave bottles containing volatile solvents or flammable liquids.

Rinse immediately after use to prevent residues from drying and hardening on the glass. For most reagents, wash with a mild laboratory detergent and a bottle brush, then rinse three times with tap water and twice with distilled water. For organic solvent residues, pre-rinse with a small amount of an appropriate solvent before washing with detergent. For stubborn organic staining, soak in a lab-grade cleaning solution such as 10% nitric acid or a chromic acid bath (following appropriate safety protocols). Allow to air-dry inverted on a drying rack.

For organic solvents, use a narrow-neck borosilicate glass reagent bottle with a precision-ground glass stopper. Apply a very thin film of silicone grease around the stopper cone to create a solvent-tight seal and prevent the stopper from seizing. Alternatively, a screw-cap bottle with a PTFE-lined lid is more convenient and still provides good resistance to most organic solvents. Avoid rubber or standard plastic caps with aggressive solvents like chloroform, dichloromethane, or acetone, as these will cause the cap to swell and fail.