Microfluidic Bonding Technology in the IVD Industry

The full name of IVD is invitrodiagnosticproducts, which is translated into in vitro diagnostic products in Chinese. IVD refers to medical devices, in vitro diagnostic reagents and drugs. As a branch of medical devices, IVD is a special regulation and law. As an independent branch of medical devices, IVD has its own unique definition and management system internationally, especially the US Food and Drug Administration (FDA) and the European Union (EC). IVD mainly includes instruments, reagents or in vitro diagnostic systems. However, in China, there is no separate distinction and definition for IVD, that is, there is no concept of IVD. In addition, common products in the IVD concept are also scattered in different fields such as medical devices, in vitro diagnostic reagents and drugs. In addition to the use of radionuclide labeling for blood source screening, IVD products are also defined as in vitro diagnostic reagents for drug management.

Today we are discussing the application of microfluidic chips in plastic laser welding IVD products, which is a new technology platform for processing extremely small amounts of liquid. Microfluidic technology is widely used in biology. Its main features and advantages are that cell culture, experimental processing, imaging, detection and other links are highly integrated on the chip. Microfluidic control chips are composed of microchannels, micropumps, microvalves, etc. As the chip becomes smaller, the requirements for the selection of required materials and processing equipment will become higher and higher. At present, in pursuit of large-scale, cheap, and highly plastic chip manufacturing, most choose organic polymers as the main material, which also opens up new areas for the application of laser welding.

Now, we know that traditional microfluidic chip sealing technologies include ion bonding, thin film method, ultrasonic welding, hot pressing connection, etc., and laser welding is an emerging welding technology in recent years. Compared with several other sealing methods, plastic laser welding has obvious advantages such as high welding accuracy, firmness, airtight sealing, less degradable resin, and less debris.

The advantages of no residue laser welding make it more suitable for drugs controlled by the State Food and Drug Administration, especially a large number of microchannels in microfluidic control products. Laser control computer is convenient and can flexibly reach every detail of the parts. Compared with other melting methods, laser welding greatly reduces the vibration stress and thermal stress of the product, and greatly reduces the aging speed of the product.

Currently, microfluidic chips mainly use PC+PC. The mainstream welding direction of PMA+PMA and other materials is transparent+black welding. Transparent+transparent welding. The two welding laser bands are also different. For example, in the traditional transparent and black opaque material welding, we choose laser welding with a laser type of about 1000nm, and for special welding methods such as transparent welding, we will use laser welding of about 2000nm. As can be seen from Figure 1, the laser penetration of the ordinary 1000nm band reaches more than 95% in transparent and transparent PC welding. Since T (penetration) + R (reflectivity) + A (absorption) = 1, the welding reflectivity of flat plastics is almost 0, so it is easy to conclude that the absorption rate of 100nm band lasers for transparent materials is only about 5%. But the laser transmittance of the 2000nm band is only about 5%-20%, and the absorption rate is 80%-90%.

There are many problems in the field of laser welding for transparent plastics, such as.

1. Bending after welding.

2. Flow path fusion during welding.

3. Tumors are generated during welding.

4. Bubbles are generated during welding.

5. No strength at the depth of fusion.

We can solve the above problems from many aspects.

1. Optimize the optical mode.

2. Improve the laser process.

3. Increase the quality monitoring technology of the equipment itself to form a closed-loop control. Therefore, in the field of plastic lasers, it not only has equipment manufacturing capabilities, but also equipment manufacturing capabilities + laser independent development capabilities + overall process solutions.

Our company has its own full set of process solutions in the market in this field, and has developed a transparent plastic laser welding laser, which brings great flexibility and convenience to the development of the project, with better laser control. The laser is controllable, the development is flexible, and the equipment has good stability.