Fluorescent Signaling of Molecularly Imprinted Nanogels Prepared via Postimprinting Modifications for Specific Protein Detection

Abstract

Previous reports have stated the advantages of postimprinting modification (PIM) to develop multifunctional molecularly imprinted polymers (MIPs). However, existing technologies have only been applied on bulk‐ and film‐based MIPs. Herein, the fluorescent signaling of nanogels (NGs) for protein detection is demonstrated. The NGs are prepared by molecular imprinting and PIM. A bivalent functional monomer, 4‐[2‐(N‐methacrylamido)ethylaminomethyl] benzoic acid (FM1), comprising a benzoic acid moiety for interaction with proteins and secondary amine group for incorporating fluorescent reporter molecules is used. Human serum albumin (HSA), a marker protein for human health, serves as the model protein. HSA‐imprinted NGs (MIP‐NGs) are prepared by emulsifier‐free precipitation polymerization of FM1, N‐isopropylacrylamide, 2‐methacryloxyethyl phosphorylcholine, and N,N′‐methylenebis acrylamide in the presence of HSA. After the removal of HSA, a fluorescent dye (ATTO 647 N) is treated with amino groups on FM1 residue as the PIM; this yields fluorescent‐signaling MIP‐NGs (FL‐MIP‐NGs) of ≈20 nm in diameter. The FL‐MIP‐NG‐based sensing system detects HSA in a real sample by selectively reading out the HSA‐binding events as high‐affinity fluorescence changes (Kd = 2.5 × 10−9 M). The proposed MIP‐NGs functionalized via PIMs serve as advanced functional materials for sensing biorelated compounds.

Multicolor Polystyrene Nanosensors for the Monitoring of Acidic, Neutral, and Basic pH Values and Cellular Uptake Studies

“…Such measurements commonly utilize molecular and nanoscale fluorescent probes and sensors which undergo target-specific changes of the intensity and/or spectral position of their absorption and/or fluorescence or changes in their fluorescence lifetime and emission anisotropy. Targets that are fluorometrically detectable with the aid of such probes and sensors include environment parameters like temperature, viscosity, and polarity; gases like oxygen; , and ionic analytes such as protons (pH), , metal ions, , and anions; as well as neutral species like certain enzymes, proteins, and carbohydrates such as glucose. , …”

Customizable molecular recognition: advancements in design, synthesis, and application of molecularly imprinted polymers

“…Additionally, Tsutsumi et al continued to investigate PIM-MIPs for the specific fluorescent detection of proteins through nanogels instead of bulk- and film-based MIPs. 104…”

“…Additionally, Tsutsumi et al continued to investigate PIM-MIPs for the specific fluorescent detection of proteins through nanogels instead of bulk-and film-based MIPs. 104 This time, utilization of a bivalent functional monomer enabled specific target protein binding alongside the addition of secondary amino acid groups. HSA was used as the template protein for imprinting of the nanogels.…”

Multi-Functional Nanocavities Fabricated Using Molecular Imprinting and Post-Imprinting Modifications for Efficient Biomarker Detection

“…MIP-nanogels that emit fluorescent signals for HSA were prepared using the emulsifier-free precipitationpolymerization technique, with MABA serving as the functional monomer (Fig. 9a) [37]. Dynamic light scattering, and transmission electron microscopy (TEM) were used to characterize the nanogels, revealing the diameter of the purified nanogel to be 18 nm (Fig.…”