“Smart” Biopolymer for a Reversible Stimuli-Responsive Platform in Cell-Based Biochips

Abstract

The rapid response of a smart material surface to external stimuli is critical for application to cell-based biochips. The sharp and controllable phase transition of elastin-like polypeptide (ELP) enabled reversible cell adhesion on the surface by changing the temperature or salt concentration in the system. First, ELP micropatterns were prepared on a glass surface modified into aldehyde. The lysine-containing ELP (ELP-K) was genetically synthesized from E. coli for conjugation with the aldehyde on the glass surface. The phase transition of ELP was monitored in PBS and cell culture media using UV-visible spectroscopy, and a significant difference in transition temperature (Tt) was observed between the two solution systems. The micropatterning of ELP on the glass surface was performed by microcontact printing a removable polymeric template on the aldehyde-glass followed by incubation in ELP-K aqueous solution. The ELP micropatterns were imaged with atomic force microscopy and showed a monolayer thickness of approximately 4 nm. Imaging from time-of-flight secondary ion mass spectroscopy confirmed that the ELP molecules were successfully immobilized on the highly resolved micropatterns. Cell attachment and detachment could be reversibly controlled on the ELP surfaces by external stimuli. The hydrophobic phase above Tt resulted in the adhesion of fibroblasts, while the detachment of cells was induced by lowering the incubation temperature below Tt. The smart properties of ELP were reliable and reproducible, demonstrating potential applications in cell-based microdevices.

Fabrication of Thermo-Responsive Molecular Layers from Self-Assembling Elastin-Like Oligopeptides Containing Cell-Binding Domain for Tissue Engineering

“…Furthermore, the ELPs potentially offer several advantages over PNIPAM such as biocompatibility and biodegradablility characters. Based on such interesting properties, ELPs have already been employed as useful molecular tools for biological applications such as protein purification, drug delivery and artificial ECM [17][18][19][20][21][22][23][24][25][26]. In most of these studies, genetically engineered ELPs with high molecular weights were used on the subjects.…”

Versatile Gradients of Covalently Bound Proteins on Microstructured Substrates

“…It has been reported that the geometry of the cellular microenvironment has a major impact on cell fate and function, and it can control cell differentiation 23 or guide cell migration, 24 ultimately leading to dramatic consequences for tissue function. 25 However, it is challenging to combine topographical structures and biomolecular gradients. Wang and co-workers used microstructures in a microfluidic channel to overcome the effects caused by shear stress in neuronal growth cones.…”

Elastin‐Like Macromolecules

“…For bone tissue engineering, an ELR-RGD has been adsorbed onto micropatterned poly(N-isopropyl acrylamide) films displaying a positive maintenance of the cell attachment in the scaffolds under dynamic culture conditions [168]. Hyun et al [169] have also developed a lysine-containing ELR conjugated onto an aldehyde-glass surface by micropatterning. The sharp and controlled phase transition of ELR enabled reversible cell adhesion on the surface by changing the temperature or salt concentration, demonstrating potential applications for cell-based microdevices.…”