Dimension 3100 spm

Surface wettability of the PMAn films through photo-reaction was investigated by water (DI) drop contact angle measurement. PMAn films were illuminated by high intensity UV source for 1, 3, 5, 10 mins. For surface morphology experiments, the polymer films on silicon wafer were illuminated by a high-intensity UV source for 15 min through a 10 μm line pattered photomask. AFM analyses were carried out at room temperature with a Dimension 3100 SPM equipped with Nanoscope IVa devised by Digital Instruments from Santa Barbara, CA. The AFM tip was oscillated at its resonance frequency (75 kHz). Next, the tip was lifted with fixed distance above the sample surface and scanned at that constant height with a voltage applied.

¹H spectrum was determined on a Bruker ARX-300 spectrometer. The average molecular weight of the polymer was characterized by a gel permeation chromatography (GPC) (model: Waters R-401 ALC/GPC) with THF as an eluent and polystyrene standard for calibration. Fluorescence spectra were obtained with a luminescence spectrometer (PerkinElmer, Model LS55) under excitation at 370 nm. The polymer films were illuminated with a UV lamp (Rolence Enterprise, Inc., Taiwan, power: 13.05 mW/cm²), model POWERARC UV 100. The surface wettability was investigated by a water (DI) drop contact angle measurement using Contact Angle Meter-CAM 101 model (KSV Instruments Ltd, FINLAND). AFM analysis was carried out in room temperature with a Dimension 3100 SPM equipped with Nanoscope IVa devised by Digital Instruments from Santa Barbara, CA. The fluorescent patterns such as were imaged under Olympus-BX51 fluorescence microscope with WB – dichroic mirror DM500, excitation filter BP450-480 and barrier filter BA515. The optical MSCs patterns were obtained from Olympus inverted research microscope model IX71. To detect cell patterns more in detail, MSCs were observed with field emission-scanning electron microscope (HITACHI S-800, Tokyo, Japan) and the picture was taken by scanning microscope image analysis system (ESCAN-4000, Bummi Universe, Tokyo, Japan)

The optoelectronic features of the device were explored using a semiconductor parameter analyzer (HP 4145B, Center for Detectors, Rochester, NY, USA) and a probe station, with an incident light power of around 4.5 mW cm⁻². Measurements were performed under dark conditions and under illumination with light at wavelengths (λ) of 405, 450, 520, and 635 nm. The transmittance of the films was measured by a UV–visible spectrometer (Cary100, Agilent, Santa Clara, CA, USA). The device structure was analyzed by carrying out cross-sectional HR-TEM measurements using a JEM-2100F system (JEOL Ltd., Tokyo, Japan). Surface topologies and the RMS values of films were investigated by AFM (Dimension 3100 SPM, Digital Instruments, Tonawanda, NY, USA). XPS and UPS analysis (Thermo Fisher, NEXSA, Waltham, MA, USA) were conducted to investigate the interfacial properties with Al Kα (1486.8 eV) and He–I line (21.22 eV) sources, respectively.