A glass syringe is a glass barrel with a plunger. It is used to draw out or inject fluids and gasses. Glass syringes can have a variety of tips attached to them, from needles for vaccines to a wide tube for feeding baby animals. Originally, all syringes were made of glass, but plastics have emerged as a contending material.
There is a long history in the medical profession of using glass syringes. In the 9th Century Anno Domini (AD), the surgeon Ammar ibn Ali was using a glass syringe to suck soft cataracts out of the eyes of his Egyptian patients. In 1946, the English Chance brothers began mass-producing glass syringes. All the plungers, barrels and needles were interchangeable and could easily be sterilized.
Today, glass syringes are still used, but they are competing with plastic. Compared to a glass syringe, a plastic syringe can more easily create a tight seal for the plunger. Concerns about cross-contamination have made disposable plastic syringes a norm in the medical industry, where after one use, the syringe is thrown away.
The development of syringes with pre-measured dosages inside for home treatment of diabetes, however, has led to questions about whether plastic syringes really are better. When one-dose syringes are stored for long periods, plastics can leach trace amounts of chemicals into the medication. With new medicines, which rely on antibodies and certain kinds of proteins which can absorb plasticine, storing them in plastic can change the chemical composition of the medicine.
A glass syringe contains much lower levels of contaminants that will react with delicate cures. They may leach traces of certain metals into a medicine, but these trace amounts do not react with medicine as poorly as plastics. Unfortunately, the plungers of glass syringes may also be coated with silicone in order to make them slide more easily, and this lubricant can also react poorly with medicine.
Glass syringes are also a better choice when storing blood samples that will later be used for arteriolar blood gas (ABG) testing. An ABG test is used to determine the pH of blood, its level of oxygen and nitrogen and many other attributes. It's used to diagnose many conditions, such as whether or not the blood is becoming oxygenated in the lungs. A glass syringe is less porous than plastic; therefore, fewer gasses will escape from the blood while it is being held for study.