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Medical infusion bag heat seal strength monitoring program

May 03,2024

Source: Link Testing Instruments Co.,Ltd.

With the gradual increase in the types of soft plastic packaging and the continuous improvement of performance, traditional infusion glass bottles are being replaced by soft plastic infusion bags. Common soft plastic infusion bags are mostly made of polypropylene, polyethylene, polyamide and various elastic materials through a co-extrusion process. Compared with traditional glass bottles, soft plastic infusion bags are environmentally friendly, hygienic and not fragile. It has advantages such as convenient use and transportation. In order to ensure that the medicinal liquid does not leak during transportation and storage and that the quality is intact, the heat seal strength of the infusion bag seal is a performance that must be considered during use.

The heat seal is a barrier that separates the medicinal solution in the infusion bag from the outside environment. If the heat seal strength is poor, the medicinal solution will easily leak, and the gas in the environment will easily penetrate into the infusion bag, causing the components of the medicinal solution to oxidize and fail, or even Harmful substances are produced. In addition, if the bag is squeezed or dropped by external force during transportation or storage, the bag may be broken in the poor heat seal area. During the filling process of medicinal liquid, droplets are likely to contaminate the heat seal, affecting the heat seal strength of the seal. Therefore, it is necessary to strengthen the monitoring of the heat seal strength of medicinal infusion bags.

Test methods and test instruments

This test process is based on the pharmaceutical packaging material standard YBB00122003-2015 "Heat Seal Strength Test Method". This standard is suitable for the measurement of the heat seal strength of plastics heat-sealed on plastics or other substrates and the heat seal strength of plastic composite bags.

The test uses the LTS-05 pharmaceutical packaging performance tester to test the heat seal strength of the sample. This equipment is independently developed and produced by Link Testing Instruments Co.,Ltd. is a professional instrument used to test the mechanical properties of various pharmaceutical packaging materials; its ultra-high precision (level 0.5) ensures the accuracy of the test; 16 independent test procedures, various specifications of force sensors, And the tensile and compression bidirectional test mode can meet the various testing needs of users.

Heat seal strength test principle: Heat sealing strength refers to the force required to pull apart and destroy the heat-sealed edge. The equipment is equipped with two upper and lower clamps for clamping both ends of the sample, and the sample is moved by the movement of the upper clamp. The heat-sealed edge is pulled apart and destroyed. The upper clamp is equipped with a force sensor, which can real-time monitor the force value changes generated during the heat-sealed edge being destroyed, and display the tested force value on the force value curve, thereby obtaining the sample's force value. Heat seal strength.

Test samples and test process

Test sample: The test uses a certain brand of infusion bag as a test sample to detect its heat seal strength.

Experimental procedure:

(1) At the four heat-sealed edges of the sample, cut a total of 10 samples with a width of 15 mm and an unfolded length of at least 100mm in the direction perpendicular to the heat-sealed edges.

(2) Set parameter information such as sample name, test speed 300 mm/min, sample width 15 mm, etc.

(3) Take one of the samples, open it with the heat-sealed edge as the center, and clamp both ends of the sample in the upper and lower clamps of the equipment so that the axis of the sample coincides with the center line of the upper and lower clamps, and the heat-sealed edge Try to keep the distance between the two clamps equal.

(4) Click the Start option to start the test. The upper clamp moves upward according to the set test speed and drives the heat-sealed edge to be destroyed, and the force value changes are displayed in real time.

(5) At the end of the test, the device displays the heat seal strength of the tested sample.

(6) Repeat (3) ~ (5) until all 10 samples are tested.

Test results and analysis

The test results of the 10 samples are 35.625 N/15mm, 33.649 N/15mm, 34.056 N/15mm, 36.790 N/15mm, 32.483 N/15mm, 36.020 N/15mm, 34.631 N/15mm, 33.549 N/15mm, 34.156 N/15mm, 36.048 N/15mm. The heat seal strength of the tested medicinal infusion bag sample is the average of the test results of 10 samples, which is 34.701 N/15mm.

Good heat seal strength is one of the necessary conditions to keep the packaging of medicinal infusion bags intact and ensure drug efficacy. It is of far-reaching significance to strengthen the monitoring of the heat seal strength of infusion bags.

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