The pharmaceutical rubber stopper is an integral part of medicine. Its main function is to seal and store the medicine in a relatively small aseptic inert environment, isolated from the external common environment so that the medicine can maintain its efficacy within the validity period. If there is an abnormality of the rubber stopper, the medicine may become invalid or even deteriorate, posing a threat to the lives of the people. The physical properties of the rubber stopper play a decisive role in the sealing of the medicine. The physical properties of rubber stoppers are very important and indispensable to the quality of medicines.

Insoluble particles of rubber stoppers

The insoluble particles that fall off the surface of the rubber stopper are divided into two types, one is liquid droplets that are insoluble in water, and the other is solid particles. Liquid insoluble particles are mainly silicone oil droplets that fall off the surface of the rubber stopper. This type of insoluble particles can be combined with the powdered drug to make the powder insoluble and affect the efficacy. More seriously, it will reduce the transparency of the drug solution and increase the turbidity, resulting in a phase the capacity is unqualified. The sources of solid insoluble particles are not only the components separated from the rubber stopper formula but also foreign pollution particles; the mutual squeezing and friction of the rubber stoppers during production and transportation will generate particles again. When such insoluble particles come into contact with the liquid medicine, they may enter the liquid medicine and affect the quality of the medicine.

Improvement plan: Design a rubber stopper formula that is not easy to precipitate to reduce the composition of the formula to the surface of the rubber stopper; clean production, reduce particle pollution; optimize transportation methods, reduce friction, and reduce the amount of silicification.

 

The sealability of rubber stopper and container

The main function of the pharmaceutical rubber stopper is to provide a good seal for the medicine contained in the bottle to prevent the medicine from being contaminated by bacteria and deterioration. Therefore, the importance and necessity of the inspection of the rubber stopper are self-evident. At present, the main materials of domestic rubber stoppers are isoprene rubber or butyl rubber (including chlorobutyl rubber and bromobutyl rubber), both of which have good sealing performance, especially butyl rubber has better airtightness. It is suitable for the production of pharmaceutical rubber stoppers.

Improvement plan: With butyl rubber as the main material, with other additives and processing technology, the production of different specifications of pharmaceutical rubber stoppers can meet the sealing requirements of different specifications of bottles.


 

Puncture force of rubber stopper

Most of the medicinal rubber stoppers are punctured when the medicine is used. The purpose is to puncture the rubber stopper, pour injection water into the medicine bottle (bag) to dissolve the medicine, or absorb the liquid medicine in the medicine bottle (bag), and then inject it into the human body. This requires a relatively moderate puncture force of the rubber stopper. If the puncture force of the rubber stopper is too large, it will be more difficult for the nurse to operate, which may cause accidents. The factors that affect the puncture force of the rubber stopper include: the high hardness of the rubber stopper, less silicone oil on the surface of the rubber stopper, the improper fit between the rubber stopper and the supporting packaging material, and the puncture device is not sharp enough.

Improvement plan: From the formulation design to make the rubber stopper hardness moderate. From the process design, appropriately adjust the amount of silicone oil on the surface of the rubber stopper. From the rubber stopper structure design to make the rubber stopper and the supporting packaging material fit properly. Select a good quality puncture device, etc. Then we can effectively solve the problem of the large puncture force of the rubber stopper

 

Sealing after puncture

Sealing after puncture, including inspection items such as self-sealing, sealing at injection points, and leakage of needles. Most medical rubber stoppers need to be punctured when used in terminal hospitals. This not only requires that the rubber stopper has a good seal when it is not punctured but also has a good seal after being punctured to ensure the medicinal container ( For example, the integrity of the bottle), to ensure that the liquid medicine will not leak from the puncture hole during the process of liquid withdrawal and infusion. The main reasons for the poor sealing performance of the rubber stopper after puncture are: poor puncture performance of the rubber stopper, large pieces of debris are produced, and the incision cannot be closed; the elasticity of the rubber stopper is poor, and it cannot rebound quickly to close the incision after being punctured; The thickness of the part is insufficient, and the effect of closing the incision is not good; the rubber stopper has poor compatibility with the bottle and aluminum cap (too loose), etc.

Improvement plan: Optimize the structure, formula and process of the rubber stopper, improve the compatibility of the rubber stopper and the supporting packaging materials, improve the puncture chipping performance and resilience of the rubber stopper, and ensure that the sealing performance of the rubber stopper is qualified after a puncture.

Puncture and chip drop performance

Pharmaceutical rubber stoppers in the end-use often will be punctured. in the process may produce fallen chips into the drug solution, and the number and size of these fallen chips will affect the quality of the drug, so control of plugs punctured fallen chips is very necessary. The main reasons for rubber stopper puncture and chipping are rubber stopper formula technology level, cooperation with other packaging materials, rubber stopper processing methods, puncture quality, operator's technique, use environment, etc.

Improvement plan: increase the rubber content of the rubber stopper, appropriately reduce the product hardness, and appropriately increase the amount of siliconization on the surface of the rubber stopper; the matching degree of the rubber stopper is appropriate, and it cannot be too loose or too tight; the rubber stopper processing method is reasonable; the quality control of the puncture device; Operators are trained in standardized operations; the puncture environment meets the standard requirements, etc.

Puncture device retention

The Puncture device retention includes static retention (needle hanging force) and dynamic retention. Pharmaceutical rubber stoppers used for sealing injection drugs are often used in conjunction with disposable infusion sets for a long time. This requires the rubber stoppers to have a certain static and dynamic retention force, and the infusion set should not fall off during use, so as to avoid accidents. The reasons for the insufficient retention of the puncture may include large silicone oil on the surface of the rubber stopper; low hardness of the rubber stopper; too thin puncture part of the rubber stopper; loose fit with the supporting packaging materials, etc.

Improvement plan: reduce the silicone oil on the surface of the rubber stopper; increase the hardness of the rubber stopper; thicken the puncture part of the rubber stopper; improve the fit between the rubber stopper and the supporting packaging material (appropriate tightness), etc.