Laboratory Syringes

Choose a syringe volume where the amount you need to dispense falls between 20% and 80% of the barrel capacity for the best accuracy. A 1 ml syringe is ideal for micro-volume injections up to 0.8 ml. A 10 ml syringe suits 2 ml to 8 ml dispensing. A 50 ml syringe is used for gas volume capture experiments and larger reagent volumes.

Luer-slip syringes have a tapered tip that friction-fits to a needle or connector. Luer-lock syringes have a threaded collar that screws onto a matching luer-lock needle or fitting, preventing accidental disconnection under pressure. For any application involving a connected needle, filter, or tubing that could detach under plunger pressure, use luer-lock.

Disposable syringes are pre-sterilised and eliminate cross-contamination between samples. They are the standard choice for biological, diagnostic, and clinical applications. Reusable glass or PP syringes are preferred for organic chemistry work where the syringe will contact organic solvents that attack the materials in disposable syringes, and where the syringe must be cleaned and rinsed between uses.

Disposable syringes have plunger seals made from rubber or silicone. These seals are compatible with most aqueous solutions. Concentrated organic solvents, oils, and aromatic chemicals can swell or dissolve the plunger seal, causing leaks and inaccurate volume delivery. For organic solvents, use a syringe specifically rated for solvent use, or select a glass syringe with a PTFE-tipped plunger.

A luer-slip syringe has a smooth tapered tip that pushes into a compatible needle or connector by friction. A luer-lock syringe has a threaded outer collar that screws onto a matching luer-lock needle or fitting, creating a mechanically locked connection that cannot pull apart under pressure. Luer-lock is safer and is required whenever the syringe is connected to a needle or fitting under plunger pressure or in a moving system.

Standard disposable PP syringes resist mild aqueous and mildly acidic solutions. Concentrated organic solvents including acetone, ethanol above 70%, chloroform, and DMSO can swell or dissolve the plunger tip seal material, causing leaks and sample contamination. For organic solvent work, use syringes specifically rated for solvent use, or select a glass barrel syringe with a PTFE plunger tip that is inert to virtually all laboratory solvents.

They share the same mechanical design and luer fitting standard, but medical syringes are manufactured and packaged under stricter pharmaceutical sterility standards and are often sold with needles attached. Laboratory syringes are designed for chemical and sample handling and may not carry medical-grade sterility certifications. For biological or cell-culture work requiring medical-grade sterility, use individually sterile laboratory syringes or medical-grade syringes without needles.

Connect the syringe tip to the gas outlet of your reaction vessel with flexible tubing or place the tip against the outlet and pull the plunger out slowly as gas is produced. Prevent backflow by pinching the tube after each reading if measuring intermittently. Read the gas volume directly from the graduated barrel. Ensure the syringe plunger moves freely and that there are no air leaks in the connections before beginning the experiment.

Disposable plastic syringes are designed for single use and should not be reused, as the plunger seal degrades after the first use, giving inaccurate volumes on subsequent draws. Reusable laboratory glass syringes and certain PP syringes are designed for repeated use with cleaning between applications. If reusing a syringe, rinse it immediately after use, clean with laboratory detergent and distilled water, and check that the plunger moves smoothly before the next use.