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This paper reports a simple method for creating a functionalized surface for the efficient micro/nanopatterning of proteins by micromolding in capillaries (MIMIC) of poly(ethylene glycol)-poly(lactide) diblock copolymer (PEG-PLA) and self-assembled polyelectrolyte multilayers (PEL). The fabricated surface consisted of two distinct regions: a PEL region to promote protein immobilization and a PEG-PLA background as a biological barrier to prevent the nonspecific binding of proteins. When the ability of anti-biofouling of PEG-PLA was compared with the most widely used blocking agents, such as bovine serum albumin (BSA) and skim milk, the PEG-PLA prevents the nonspecific adsorption of several proteins. The properties of a functionalized surface were characterized by the water contact angle and atomic force microscopy (AFM). Topological analysis clearly indicated that the MIMIC method provides a reliable surface regardless of the micro-and nanopattern size. Two different functionalities of the fabricated surface produce uniform protein patterns from the micro-to nanoscale with a high signal to noise ratio. The proposed method allows for flexibility in forming shapes, such as lines, squares, circles, triangles and stars, and can control the pattern size from 400 nm to 90 µm. Finally, the antigen-antibody assay showed good linearity over the range of 10 ng/mL to 25 µg/mL, indicating its feasibility for a quantitative measurement of the concentration of target proteins in a sample.

A new polymer conjugate of poly(ethylene glycol) (PEG) and 10,12-pentacosadiynoic acid (PCDA), PEG-PCDA conjugate, was synthesized by coupling reaction between carboxyl group of PCDA and hydroxyl group of PEG. Luminescent CdSe/ZnS QDs were encapsulated in the polymer micelles of mixtures of PEG-PCDA and PCDA using solid dispersion method to prepare water-soluble and biocompatible QD micelles. Upon UV-irradiation, the core of QD micelles was further stabilized by intramicellar crosslinking between neighboring PCDA moieties. The polymer conjugate was characterized by 1H-NMR, FT-IR, and GPC measurements, and thereof QD micelles observed using transmission electron microscopy (TEM) and dynamic light scattering (DLS). The QD micelles were spherical with diameters in the range of 30-190 nm. The encapsulated QDs in polymer micelles are water-soluble and have the high potential for applications in biomedical imaging and detection due to their good colloidal stability and biocompatible surface.

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