Surface Modification and Functionalization Service
Inquiry
Physical attachment of biomolecules to substrates is often unfavorable in microfluidics, especially at high flow rates where the separation of immobilized biomolecules is very likely. Our cutting-edge microfabrication technology platform and years of experience in biology ensure Creative Biolabs provides our clients with the most comprehensive, stable and flexible microfluidic channel surface modification and functionalization services.
Surface Modification and Functionalization for Micro-Channels
In order to enable the chip for specific biological/chemical functions, functionalization of the channel surface is essential. Unmodified channels show poor biomolecule attachment efficiency and even lead to the denaturation of such molecules. The hydrophilicity/hydrophobicity of the channel surface is also a key factor affecting the success of various chemical synthesis experiments. Creative Biolabs provides various surface modification technologies and biofunctionalization approaches to modify the biocompatibility of chip materials, achieve strong immobilization of biomolecules and customize channel surface properties. You are more than welcome to choose from various surfaces with different properties.
Fig 1. Micro-channel surface modification and functionalization methods. (Shakeri, et al., 2021)
We directly provide our clients with raw material microfluidic chips without any surface modification. You can directly conduct experiments or perform custom surface functionalization on these chips. It should be noted that most of the polymer chips are hydrophobic although the wetting angles are different.
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Physical Structure Functionalization
Microstructures on the channel surface (pillars, weirs, micro pits, etc.) can trap and adsorb particles. Entrapments tend to be stronger than hydrophobic sorbents at lower flow rates and also offer the possibility for non-specific adsorption.
Amination is the most commonly used technology for the covalent attachment of biomolecules. Amino groups on the channel surface can directly combine with carboxyl groups of biomolecules to form a highly stable connection. The surface of the channel after amination treatment has good hydrophilicity with a positive charge, which promotes biocompatibility and cell adsorption of the surface.
Oxygen plasma treatment and UV irradiation can provide a layer of -OH groups on the channel surface and greatly promote the hydrophilicity of the surface. These negatively charged groups effectively improved the biocompatibility of the chip. It is worth noting that the -OH groups produced by hydroxylation are rapidly inactivated over time, so are mostly used for providing reactive sites for downstream modifications.
Fig 2. Surface modification by grafting. (Nady, et al., 2021)
Carboxylation is similar to amination, except that carboxyl groups are generated on the surface of the material and connected to the amino groups of biomolecules through carbodiimide. Carboxylated channels will be hydrophilic and negatively charged.
The epoxy groups induced by reagents can be covalently bonded to the amino groups of biomacromolecules, thereby providing highly stable biomolecular bonding functions without the need for crosslinkers.
We can coat or fill channels with various hydrogel materials to provide wettability and biocompatibility inside the structure. The hydrogel can be further functionalized to immobilize biomolecules or provide specific physical/chemical properties. In addition, we also perform particle coatings to form an inert hydrophilic protective layer, but it is worth noting that such particles are often biologically toxic, so they are only suitable for physics/chemical research.
Biotin can form stable linkages with streptavidin-conjugated molecules through robust and nonspecific adsorption. Biotin-PEG-modified microfluidic chip channels tend to have excellent biocompatibility and molecular solidification stability.
We provide printing and deposition services for a wide variety of metals. These patterned metals will provide additional molecular binding sites and biocompatibility on the chip, and can be used as microelectrodes to convert chemical/biological signals into intuitively accessible electrical signals.
Other Services
Modified and functionalized materials may overcome inherent disadvantages or add new functions. Creative Biolabs maximizes the use of advanced machining platforms and optimized micro-processing concepts to help our clients create the desired surface properties or immobilize functionalized biomolecules. Years of biological experience also allow us to offer conjugation service of different biomolecules or to complete any downstream testing on your commission. With our help, you can customize the physical and chemical properties as well as conjugated molecules on the channel surface of the microfluidic chip to achieve diversified functions, so please don't hesitate to contact us for any needs.
References
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Shakeri, G.; et al. Bio-functionalization of microfluidic platforms made of thermoplastic materials: A review. Analytica Chimica Acta. 2021, 1029: 339283.
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Nady, E.; et al. Functionalization of microfluidic devices by microstructures created with proton beam lithography. Vacuum. 2021, 190: 110295.
For Research Use Only. Not For Clinical Use.
