An ampoule (also ampul, ampule, or ampulla) is a small sealed vial (the volume ranges from 1 to 25ml) which is used to contain and preserve a sample, usually a solid or liquid. Ampoules are commonly made of glass or plastics. Actually since the glass ampoule is fragile, more and more plastic ampoules are used by the medical industry, which are easy and safe to operate.

The plastic ampoule shall have sufficient oxygen barrier property, otherwise, some elements contained in the medicine may be oxidized and as a result, the color of the medicine may change or even worse the medicine may become ineffective. Therefore, it is necessary for the drug manufacturers to examine the oxygen barrier property of the plastic ampoules used for the medicines.

This article provides a simplified test method of the oxygen barrier property of the plastic ampoule for your reference. The testing instrument used for oxygen permeability tests is Labthink’s OX2/230 Oxygen Transmission Rate Test System. This instrument uses a coulometric detector to determine the oxygen transmission rate. The specimen is mounted as a sealed semi-barrier between two chambers at ambient atmospheric pressure. One chamber is slowly purged by a stream of nitrogen at a given temperature and relative humidity and the other chamber is purged by a stream of oxygen at the same temperature as the nitrogen stream but may have a different relative humidity than the nitrogen stream. In this case the environment would more closely simulate actual shelf conditions. As oxygen gas permeates through the film into the nitrogen carrier gas, it is transported to the coulometric detector where it produces an electrical current, the magnitude of which is proportional to the amount of oxygen flowing into the detector per unit time. Note: For the package specimens, nitrogen flows inside the package while oxygen flow outside the package.

Figure 1. Plastic Ampoules

The tests shall be performed according to the following procedures.

(1)    Paste the plastic ampoule on the test plate with Aradite Rapid Transparent Adhesive. Place the specimen with test plate into the package hood. Cover the specimen with a bag.

(2)    Set test temperature, test humidity and other test parameters in the software interface. Then click Test to start the test.

(3)    Adjust humidity and carrier gas flow rate as required.

(4)    The system will calculate and display the test results after tests.

For more details about OX2/230 Oxygen Transmission Rate Test System, please visit www.labthink.com

About Labthink Instruments Co., Ltd:

Labthink Instruments Co., Ltd is one leading supplier of packaging testing instruments, which is headquartered in Jinan, China and operated in Boston, U.S.A.