Defining the Interactions between Proteins and Surfactants for Nanoparticle Surface Imprinting through Miniemulsion Polymerization

Abstract

Molecular imprinting has been considered one of the most promising techniques for the preparation of synthetic receptors. In spite of the ease of the conventional imprinting methodology and its associated success with the imprinting of small molecules, the approach has its limititation for the imprinting of protein macromolecules. This is primarily due to the limited diffusion associated with the bulkiness of the template macromolecules and the incompatibility between the fragile protein template and the imprinting conditions. To resolve these issues for the successful imprinting of proteins, miniemulsion polymerization has been employed for preparing protein surface-imprinted nanoparticles. Ribonuclease A (RNase A), bovine serum albumin (BSA), and lysozyme (Lys) were used as the template proteins while methylmethacrylate and ethylene glycol dimethacrylate were the functional and cross-linking monomers, respectively, to produce particles with sizes of about 40 nm. The RNase A surface-imprinted nanoparticles displayed favorable molecular selectivity and rebinding kinetics even in an aqueous medium. However, such a molecular recognition property was not observed for the BSA- and Lys-imprinted nanoparticles. By studying the template protein−surfactant interaction using circular dichroism, it was found that a certain degree of interaction between the template protein and the micelles is required to maintain the proteins at the particle surface. It was also found that such an interaction should not be too extensive to cause a significant conformational change, or denaturation, in the proteins to ensure the recognition of proteins in their native states. This study therefore defines the important parameters required for the successful application of a simple miniemulsion polymerization strategy for protein−surface imprinting.

The rational development of molecularly imprinted polymer-based sensors for protein detection

“…126,134 An alternative approach is to imprint the protein at the interface in mini-emulsion polymerisation. 204,205 Other particle-based approaches include the deposition of thin shell layers over core particles, which ensure that the imprint sites (which resemble bulk imprints) remain within close proximity to the surface. 155,166 Particle-based approaches to protein imprinting have been reviewed by Tan and Tong.…”

Functionalization of Multi‐Walled Carbon Nanotubes and their Application for Selective Isolation of Acidic Proteins

“…Native BSA has two characteristic negative peaks at 209 and 222 nm corresponding to the absorption of the ahelices of BSA. [42] Figure 8a clearly illustrates the native state of BSA, i.e., its a-helical secondary structure in citrate buffer (pH ¼ 7). It is obvious that no conformational structure change of BSA was observed after its collection from the surface of the micro-column of PDDA-MWNT composites, as demonstrated by the similar CD spectrum in Figure 8b.…”

A Thermosensitive Monolithic Column as an Artificial Antibody for the On‐line Selective Separation of the Protein

“…[3][4][5] The imprinting of a particular protein as an artificial antibody is meaningful in the fields of proteomics and biomedicine but still presents challenges due to a number of key inherent problems related to the molecular size, complexity, conformational flexibility, and solubility of the protein. [6][7][8][9][10][11] Owing to the uniquely predetermined selectivity of the MIP protein, diverse strategies have been addressed for protein imprinting, such as bulk polymerization (3D imprinting), [12] surface polymerization (2D imprinting), [13][14][15][16] and the epitope approach. [17,18] One approach of specific interest is the use of a MIP as a HPLC stationary phase for the separation of a target protein.…”