Fabrication of user-friendly and biomimetic 1,1′-carbonyldiimidazole cross-linked gelatin/agar microfluidic devices

Abstract

We have developed a straightforward technique for fabricating user-friendly and biomimetic microfluidic devices out of a gelatin/agar gel cross-linked with 1,1′-carbonyldiimidazole. The fabrication procedure requires only inexpensive starting materials such as glass capillaries and wires to mold 3D cylindrical channels into the gel with the possibility of achieving channel diameters of 375μm and 1000μm. We demonstrate that the channel absent of gel injury can retain fluid within its dimensions for at least 7h. We also show that the device material does not autofluoresce nor provide hindrances with fluorescent imaging. A discussion of the chemical linkage identities of cross-linked gelatin/agar is included via ATR-FTIR studies. Crosslinking of the gelatin/agar is further confirmed by the lack of a gel to sol transition at physiological temperature as assessed by DSC measurements. SEM micrographs that demonstrate the 100nm mean pore width of the cross-linked gelatin/agar are provided. This device is considered biomimetic because it represents components present in the natural extracellular matrix such as collagen and proteoglycans in the form of cross-linked gelatin/agar.