Deep UV patterning of monolayers of crystalline S layer protein on silicon surfaces

Crystalline Bacterial Cell Surface Layers (S Layers): From Supramolecular Cell Structure to Biomimetics and Nanotechnology

“…[214] Investigation of the irradiated S layer lattices showed that even a dosage of about 3500 mJ cm À2 (supplied in 10 shots at 350 mJ cm À2 each) led only to a carbonization and not to an ablation of the protein. [214] As determined by scanning force microscopy the step height between exposed and unexposed areas did not reach the thickness of the intact S layers.…”

“…For this purpose, S-protein monolayers recrystallized on silicon wafers are irradiated by deep ultraviolet (DUV) laser radiation through a microlithographic mask possessing feature in the range of 1 mm to 200 nm (square and line patterns, Figure 14). [214] Drying of the S layer was necessary to avoid formation of interference fringes in the patterned S layer by a thin water layer between mask and substrate. The S layer could be completely removed by two pulses of ArF radiation (l 193 nm; dose: approximately 100 mJ cm À2 per pulse) in the exposed areas, while in the unexposed regions the structural and functional integrity was completely retained.…”

Anisotropic Crystalline Protein Nanolayers as Multi‐Functional Biointerface for Patterned Co‐Cultures of Adherent and Non‐Adherent Cells in Microfluidic Devices

“…[ 6 ] A drawback of using photolithographic patterning techniques of biological adhesion molecules, however, is the generation of interference fringes in the patterned layers due to the necessity of a thin water fi lm to be present between the lithographic mask and protein layer that preserves the native protein conformation. [ 7 ] Among soft lithography techniques, microcontact printing (µCP), stencil-based patterning and microfl uidic patterning are most frequently used for co-culture systems. [ 8 ] More recently, tip-based direct protein printing of adhesion promoters was introduced for single cell co-cultures of 3T3 fi broblasts and C2C12 myoblasts.…”

Kristalline Zelloberflächen-Schichten prokaryotischer Organismen (S-Schichten): von der supramolekularen Zellstruktur zur Biomimetik und Nanotechnologie

“…Beispielsweise können auf Silicium-Wafern rekristallisierte S-Schichten mit UV-Strahlung durch eine in der Mikrolithographie übliche Maske, die Strukturen in der Gröûe von 1 mm bis 200 nm aufweist (quadratische und linienförmige Muster), belichtet werden (Abbildung 14). [214] Zur Vermeidung von Interferenzmustern in der strukturierten S-Schicht erwies es sich als notwendig, noch vor der Belichtung den der Proteinmatrix anhaftenden dünnen Wasserfilm durch schonende Trocknung zu entfernen. Mit zwei Pulsen eines ArF-Excimerlasers (l 193 nm, Dosis: circa 100 mJ cm À2 pro Puls) konnte die S-Schicht in den belichteten Bereichen vollständig abgetragen werden, wobei in den nicht belichteten Bereichen die Struktur und biochemische Funktion des Proteingitters völlig erhalten blieb.…”

“…[214] Untersuchungen von solchen bestrahlten S-Schicht-Gittern haben ergeben, daû selbst eine Dosis von ca. 3500 mJ cm À2 (10 Pulse zu je ca.…”