Preparation of a poly (PEGDA‐co‐GMA) thin hydrogel matrix for oligonucleotide microarray applications

Abstract

BACKGROUND: Fabricating oligonucleotide microarrays with high immobilization efficiency and sensitivity by a simple surface modification route remains highly desirable in the biochip field. Here we develop a facile method to prepare a 3D crosslinking thin hydrogel film on glass slides for high-density immobilization of DNA probes. RESULTS: Thin hydrogel film using poly (ethylene glycol) diacrylate (PEGDA) as crosslinker and glycidyl methacrylate (GMA) as functional monomer was attached on vinyl group-modified glass slides by a photopolymerization technique. The effect of monomer ratios (PEGDA:GMA) on the surface hydrophilicity of the hydrogel layer and the immobilization density of DNA probes were investigated and an optimal monomer ratio of 10:1 and te maximum immobilization density of 1.4 pmol cm -2 were found. Adjusting the hydrophilicity of the hydrogel film effectively suppressed its swelling and produced a typical dense but not porous structure with a flat surface favorable for printing microarrays. The maximum immobilization density and efficiency of oligonucleotide probes on the 3D hydrogel film were 1.4 pmol cm -2 and 83%, respectively, which are superior values to those on a 1D support. The microarray had a wide detection range of target nucleotides from 15.3 pmol L -1 to 62.5 nmol L -1 . In addition, the hybridization assay demonstrated that the microarray showed high sensitivity with a limit of detection of 30.5 pmol L -1 . CONCLUSION:The poly (PEGDA-co-GMA) hydrogel film could be grafted on the glass slide by the photopolymerization technique and the DNA probe was effectively immobilized on the thin hydrogel by reacting with the epoxy groups. This strategy of attaching a thin cross-linked poly(PEGDA-co-GMA) hydrogel layer on glass slides has promising prospects in the fields of bioanalysis and microarrays.

Rational Design of Porous Poly(ethylene glycol) Films as a Matrix for ssDNA Immobilization and Hybridization

“…Along with OEG-decorated SAMs, all-PEG materials can also be used, such as PEG brushes and polymer films [ 27 , 28 , 29 , 30 ]. Alternatively, porous PEG and PEG-based films can be used, taking advantage of 3D immobilization of ssDNA in contrast to the standard 2D assemblies provided by SAM supports and usual OEG-based polymers [ 31 , 32 , 33 , 34 ]. In particular, such porous films can be efficiently formed by thermally activated crosslinking of multi-armed STAR-PEG precursors, decorated with amine (STAR-NH 2 ) or epoxy (STAR-EPX) groups, which build ethanol-amine bridges between individual arms of the precursors upon the crosslinking ( Figure 1 ) [ 35 ].…”

One-step fabrication of three-dimensional macropore copolymer-modified polycarbonate array by photo-crosslinking for protein immunoassay

“…The detection range of macropore structure is wider than that of 2D surfaces, 51,59 which is consistent with the broader dynamic range of 3D surfaces. 60,61…”

“…The detection range of macropore structure is wider than that of 2D surfaces, 51,59 which is consistent with the broader dynamic range of 3D surfaces. 60,61 The uorescence intensity increases linearly with the logarithm of the Cy3-anti-IgG concentration in the range of 0.05-1 mg mL −1 and 5-50 mg mL −1 . The linear response range of the 3D surfaces constructed by hollow silica nanoparticles 14 and nanobranched silica structure 62 is 1-100 ng mL −1 and 10 −6 to 1 mg mL −1 , respectively, which is characterized by a linear response at low analyte concentration (Fig.…”

Exploiting epoxy-rich poly(ethylene glycol) films for highly selective ssDNA sensing via electrochemical impedance spectroscopy

“…These templates can be prepared in form of PEG brushes or polymer films [36][37][38][39] but also as 3D porous films, featuring a good accessibility of the immobilized probe ssDNA by the target strands. 14,[40][41][42][43] Among other means, such porous films can be prepared by crosslinking of so-called 4-armed STAR-PEG precursors, decorated with amine (STAR-NH 2 ) and epoxy (STAR-EPX) groups, coupled with each other at the elevated temperature and building a porous 3D PEG network. 44,45 The efficiency of these films in terms of protein and DNA sensing was demonstrated in the previous work.…”