High-Precision Combinatorial Deposition of Micro Particle Patterns on a Microelectronic Chip

Abstract

The behavior of charged bio polymer micro particles when deposited onto a CMOS chip can be analytically modeled in form of the incompressible Navier-Stokes equation and the electrostatic Poisson equation, as we describe in this article. Based on these models, numerical simulations of depositions can be implemented in COMSOL that lead to improvements in the experimental setup, optimizing the size and charge distribution of the micro particles.Adapting the experiments according to the simulation results, we will show the powerful gain in deposition precision, which is essential for a contamination-free deposition and hence high quality combinatorial deposition.

Purification of Peptides in High-Complexity Arrays

“…As recently shown, the mean diameter influences the q/m-values and thus has a major impact on the quality of the deposition pattern (see I.2.4). [55] In general, the highest densities in a peptide array can only be achieved with particles smaller than the desired feature size.…”

“…[56] Based on the data from simulations, the quality of the particle deposition has recently been enhanced by using a smaller fraction of amino acid micro particles (mean diameter: 2-3 µm) for the aerosol. [55] Furthermore, the setup of the aerosol generator has been simplified and supplemented by inserting a sieve to prevent large particle agglomerates from reaching the chip surface. Currently, an aerosol generator with 20 reservoir units is used to generate high-precision deposition patterns for all 20 types of amino acid toners (see Figure 8).…”

“…Micro particles containing the Opfp-activated and Fmoc-protected amino acids were selectively addressed onto the linker-modified surfaces either using the laser printer [45] or the micro chip technique [46,55,58] . The arrays on microscopy slides (see III.4.1, Figure 46) were printed by Dr. Thomas FELGENHAUER (PEPperPRINT GmbH, Heidelberg/Germany) according to established protocols [45] using the prototype of the laser printer.…”

“…[181] In the micro chip approach, the particle deposition on "Peptide Chip 5" was conducted by Felix LÖFFLER according to the published protocol. [55] After each particle deposition step, the deposition pattern was checked. Then, the solid supports were transferred into a pre-heated oven and allowed to react at 90 …”

“…[59] Alanine particles were first deposited on every pixel of the chip using the improved particle deposition method (see Figure 51 a-b). [55] After the complete coupling and washing cycle, Fmoc-GGGYPYDVPDYAGGG-OH was coupled to each of the alanine-containing pixels as before.…”