Norland optical adhesive noa81

Polydimethylsiloxane (PDMS) was purchased from Dow Corning as a kit containing base and curing agent (Sylgard 184). Poly (acrylic acid) (PAA) with a 12% concentration was purchased from Sigma Aldrich. Positive photoresist was obtained from MicroChemicals GmbH. Chrome photolithography masks were designed in-house using Tanner L-EDIT IC Layout software and printed externally by Compugraphics International Company. Norland Optical Adhesive (NOA81) was purchased from Norland Products Inc. HUVEC and corresponding endothelial growth medium (EGM-2: EBM-2 with EGM-2 SingleQuots) were purchased from Lonza. Collagen-1 (rat tail), phosphate buffered saline (PBS), Trypsin-EDTA, Formaldehyde, as well as donkey anti-goat IgG Alexa Fluor 546, 4′, CellTracker Orange, CellTracker Green, 6-Diamidino-2-Phenylindole (DAPI), and Alexa Fluor 633 Phalloidin were purchased from ThermoFisher. Triton X-100, bovine serum albumin (BSA), (3-Aminopropyl) trietoxysilane (APTES), glutaraldehyde were purchased from Sigma Aldrich.

RTV 615 PDMS was purchased from Techsil,
UK, and photoreactive Norland Optical Adhesive (NOA) 81 was purchased
from Norland Products Inc., USA. The suspensions of colloidal particles
were prepared with carboxylate-modified 200 nm polystyrene fluorescent
colloidal spheres (Fluoresbrite YG, Polysciences, USA) and lithium
chloride salt (LiCl, 99%) purchased from Acros Organics. Aqueous solutions
were prepared with DI water (resistivity 18.2 MΩ cm) produced
from an ultrapure Milli-Q grade purification system (Millipore, USA).
The chlorinated solvent (anhydrous dichloromethane, purity ≥
99.8%), used for recovery of the microgrooved substrate, was purchased
from Sigma-Aldrich, USA.