Quality requirements for ampoule glass containers

Ampoules are used to fill injections with different properties, which not only require high-temperature disinfection, but also need to be stored in various environments. So, during prolonged contact, there will be interactions between the drug solution and the glass surface, leading to a deterioration in the quality of the injection. For example, changes in pH value, precipitation, discoloration, detachment, etc.
If the glass bottle contains excessive lye, the PH value will rise, which will lead to the degradation of PH sensitive drugs such as potassium antimonate, insulin, epinephrine, alkaloids, etc. For example, potassium antimonate will precipitate Antimony trioxide due to the increase of pH, thus increasing the toxicity of the product. If the glass container cannot resist water erosion, it will be injected into the water and sometimes there will be "peeling". When containers that are not resistant to alkali or corrosion are filled with injections with high alkalinity, such as sodium citrate, sodium bicarbonate, Sodium lactate, calcium chloride, etc., "small white spots" and "flaking" often occur, even turbidity occurs. If the high temperature resistance is poor, it is easy to burst, leak, etc. at high temperatures. The cleanliness of glass ampoules is poor, especially the pits and glass chips attached to the bottle wall that are difficult to clean, and they are easy to fall off after filling and hot pressing disinfection, becoming waste. In addition, ampoules with significant differences in shape and size are not conducive to mechanized production. For example, if the thickness difference of the neck thread is too large, glass chips or poor sealing will be generated when filling and sealing on the ampoule bottle sealing machine, resulting in problems such as fine pores or bursting heads.
In summary, glass bottles should comply with the following regulations.
(1) The glass of ampoules must be colorless and transparent in order to conveniently inspect the brightness, impurities, and deterioration of the product. (2) It should have good heat resistance, its expansion coefficient should be very small, can withstand the Thermal shock generated during cleaning and disinfection, and will not occur cold explosion during production. (3) Having sufficient physical strength to withstand the high pressure difference generated during hot pressure disinfection and damage during production, transportation, and storage. (4) It must have strong chemical stability, the pH value of the solution will not change, and it will not be corroded by the injection. (5) It has the characteristics of low melting point and easy melting. (6) There must be no bubbles, pits, or sand particles.
The key to achieving the above goals lies in its physical and chemical properties. The physical and chemical properties of glass are related to its melting state, which is the structure of the glass. The basic skeleton of glass is silicon dioxide tetrahedron, and oxides such as sodium, potassium, calcium, magnesium, aluminum, boron, and iron can improve its physical properties. Usually, the less oxidized metal in glass, the better its chemical stability and heat resistance, and the less free alkali precipitated from the glass. To meet the ampoule standard for glass, a special metal oxide is usually used to improve its performance. Ampoules are divided into neutral glass, barium containing glass, and zirconium containing glass according to their composition. Neutral glass refers to low borosilicate glass with good chemical stability, used for various infusion fluids, glucose injections, injection water, etc. Barium containing glass has good alkali resistance and can be used as an injection for strong alkaline injections (pH 0-10.5).