Serum separation gel is a key material for achieving physical isolation between serum and blood cells in blood collection vessels. At present, the separation adhesives on the market are mainly divided into two categories: acrylic ester system and resin system. There are significant differences between the two in terms of raw material composition, production process, and performance. Understanding these differences can help blood collection tube manufacturers make reasonable choices based on their own needs.
The development process of acrylic ester system
Acrylic ester system is an early type of separation adhesive used in blood collection tubes. Due to production process limitations, early products had a clear weakness - they could not tolerate radiation sterilization. Blood collection tubes need to be sterilized before leaving the factory. If they cannot be irradiated, it means that the tube cannot achieve a sterile state, which will have an impact on subsequent blood sample storage and testing results.
With the continuous improvement of the process, the separation adhesive of acrylic ester system has gradually solved the problem of radiation resistance. After formula optimization, the product can withstand irradiation sterilization without performance degradation, and the aging rate is significantly reduced. The shelf life can be extended to three years. This progress has led to the widespread application of acrylic ester systems in the field of blood collection tubes.
In terms of appearance, the separation adhesive of acrylic ester system was mainly transparent in the early stage. In practical use, some products may experience blood entrapment when centrifuged before the blood has completely coagulated - that is, blood cells are carried through the separation gel layer and enter the serum area. Meanwhile, due to the hydrophilicity of acrylic materials, long-term contact with water in the blood may lead to a slow shift in pH value.
After subsequent improvements, the above-mentioned issues have been effectively controlled. The appearance options are also more diverse, with semi transparent and opaque products appearing one after another. The pH drift problem caused by hydrophilic properties can be solved by adjusting the formula, and the pH value can remain stable even after long-term exposure to the blood environment.
Performance improvement of resin system
With the increasing demand for sample quality in clinical testing and the emergence of new application scenarios such as cosmetic medicine, serum separation gels need to meet higher standards. The resin system is a new type of separation adhesive material developed in this context.
The most significant feature of the resin system is the use of hydrophobic materials instead of traditional hydrophilic acrylic esters. Hydrophobic properties bring several direct performance improvements: the material will not undergo changes in properties due to water infiltration when in long-term contact with blood, has stronger resistance to hydrolysis, and can maintain its original physical form. In terms of specific gravity adjustment, the resin system has greater adjustment space and can more accurately match the density values required for different blood collection tube designs.
Compatibility of reagents is another key indicator in the selection of separation gels. The resin system separation gel can coexist well with commonly used anticoagulants such as heparin and EDTA, without interfering with each other, and each plays its due role. This is particularly important for blood collection vessel types that require the simultaneous use of separation gel and anticoagulant.
In terms of solvent resistance and long-term stability, resin systems perform more outstandingly compared to acrylic systems, especially suitable for scenarios with high requirements for shelf life and extreme transportation conditions.
Selection Suggestions
Acrylic ester system and resin system each have applicable scenarios. The acrylic ester system has undergone years of development, mature technology, relatively controllable cost, and is suitable for the production of conventional blood collection tubes. Resin systems have advantages in long-term stability, reagent compatibility, and customized appearance, and are used for high-end blood collection tubes or special application scenarios.
Hubei Xindesheng Material Technology Co., Ltd. has been deeply involved in serum separation gel for many years. Both acrylic acid and resin system separation gels are available for sale. With years of research and development experience, the production process of separation gel is stable, with small batch differences and all indicators meeting relevant requirements. If you have any related procurement needs in the near future, please feel free to purchase!
