Engineering of Neuron Growth and Enhancing Cell-Chip Communication via Mixed SAMs

Abstract

The interface between cells and inorganic surfaces represents one of the key elements for bioelectronics experiments and applications ranging from cell cultures and bioelectronics devices to medical implants. In the present paper, we describe a way to tailor the biocompatibility of substrates in terms of cell growth and to significantly improve cell-chip communication, and we also demonstrate the reusability of the substrates for cell experiments. All these improvements are achieved by coating the substrates or chips with a self-assembled monolayer (SAM) consisting of a mixture of organic molecules, (3-aminopropyl)-triethoxysilane and (3-glycidyloxypropyl)-trimethoxysilane. By varying the ratio of these molecules, we are able to tune the cell density and live/dead ratios of rat cortical neurons cultured directly on the mixed SAM as well as neurons cultured on protein-coated SAMs. Furthermore, the use of the SAM leads to a significant improvement in cell-chip communications. Action potential signals of up to 9.4 ± 0.6 mV (signal-to-noise ratio up to 47) are obtained for HL-1 cells on microelectrode arrays. Finally, we demonstrate that the SAMs facilitate a reusability of the samples for all cell experiments with little re-processing.

Mechanical and Electronic Cell–Chip Interaction of APTES-Functionalized Neuroelectronic Interfaces

“…Since the electronic signal transfer depends more or less exclusively on the double-layer capacitance, we expect an improvement of the electronic signal transfer for frequencies f > 1 Hz by n Cdl = (C APTES − C bare )/C bare ≈ 13%. Although this shows that APTES SAMs seem to lead to an improvement of the signal transfer in neuroelectronic applications, this effect is definitely too small to explain the observed improvement of the action potential (AP) signal transfer reported in the literature 19,30 and shown in Figure 1. Therefore, it is necessary to examine the second possible explanation for this strong improvement of the AP signal transfer, which is the improvement of the sealing resistance.…”

Development of a Dental Implantable Temperature Sensor for Real-Time Diagnosis of Infectious Disease

“…Many types of commercially available polyimides have been widely used for biosensor encapsulation and as substrates for implantable devices due to their high flexibility, electrical resistivity, thermal and chemical stability, and biocompatibility [ 24 , 25 , 26 ]. In addition to these benefits, photo-definable polyimides are easy to pattern using photo-lithography, which facilitates biosensor or bioelectronics fabrication [ 25 , 26 , 27 , 28 ]. Therefore, in this study, photo-definable polyimide (HD-8820, HD MicroSystems, Parlin, NJ, USA) served as both structural substrates and insulation layers that resulted in simplified fabrication and cost savings.…”

A simple process to tune wettability of pectin-modified silanized glass

“…Self-assembled monolayers (SAMs) and layer-by-layer (LbL) techniques provide organized thin films by adsorption of negative and positive electrolytes from a solution, forming alternative layers at a solid interface, producing uniform and stable coatings with very high surface coverage, controlled layer thickness, and minimizing nonspecific adsorption [1][2][3][4]. The development of robust methodologies for such coatings is extremely important for a myriad of applications [5][6][7], for instance as sensors [8], medical implants [9] and cell transplantation therapy [10], lubrication [11], corrosion inhibition [12], surface patterning in photoresists [13], or the prevention of nonspecific adsorption and biofouling, and for the formulation of nanoparticulate systems with controlled encapsulation [14] and release properties [15].…”