US-12618094-B2 - Core-shell nanoparticles, methods of producing the same, and uses thereof for detecting extracellular polymeric substances

Abstract

Disclosed herein is a core-shell nanoparticle exhibiting aggregation induced emission (AIE) properties. According to the embodiments of the present disclosure, the core-shell nanoparticle comprises a core and a shell layer encapsulating the core, in which the core comprises a polymeric matrix and one or more tetraphenylethane (TPE) embedded in the polymeric matrix. Preferably, the polymeric matrix is made of a hydrophobic polymer, and the shell layer is made of a hydrophilic polymer. Also disclosed herein are methods of producing the core-shell nanoparticle, and methods of detecting an extracellular polymeric substance (EPS) produced by a microorganism via using the core-shell nanoparticle.

Inventors

• Wen-Xiong WANG
• Neng YAN

Assignees

• CITY UNIVERSITY OF HONG KONG

Dates

Publication Date

20260505

Application Date

20221229

Claims (6)

1. 1 . A core-shell nanoparticle having aggregation induced emission (AIE) properties, comprising, a core comprising a polymeric matrix and one or more tetraphenylethane (TPE) embedded in the polymeric matrix, wherein the polymeric matrix is made of a hydrophobic polymer; and a shell layer encapsulating the core, wherein the shell layer is made of a hydrophilic polymer.
2. 2 . The core-shell nanoparticle of claim 1 , wherein the hydrophobic polymer is selected from the group consisting of polyethylene (PE), polystyrene (PS), polyvinylchloride (PVC), poly (N-vinylpyrrolidone) (PVP), polytetrafluorethylene (PTFE), polydimethylsiloxane (PDMS) and polyurethane (PUR).
3. 3 . The core-shell nanoparticle of claim 2 , wherein the hydrophobic polymer is PS.
4. 4 . The core-shell nanoparticle of claim 1 , wherein the hydrophilic polymer is a copolymer consisting of two monomer units independently selected from the group consisting of methacrylic acid (MAA), methyl methacrylate (MMA), acrylic acid (AA), methyl acrylate, acrylamide, and ethylenimine.
5. 5 . The core-shell nanoparticle of claim 4 , wherein the copolymer consists of two monomer units of MAA and AA.
6. 6 . The core-shell nanoparticle of claim 1 , wherein the average diameter of the core-shell nanoparticle is about 140 nm.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS This application relates to and claims the benefits of U.S. Provisional Application No. 63/296,743 filed Jan. 5, 2022; the content of which is incorporated herein by reference in its entirety. BACKGROUND OF THE INVENTION 1. Field of the Invention The present disclosure in general relates to the field of nanoparticles. More particularly, the present disclosure relates to a core-shell nanoparticle exhibiting aggregation induced emission (AIE) properties, and uses of the core-shell nanoparticle for detecting extracellular polymeric substance (EPS). 2. Description of Related Art EPS is composed of complex high-molecular-weight mixtures of biopolymers exported from intracellular space by various microorganisms, such as microalgae, bacteria, and fungi, which subsequently form an extracellular polymeric matrix. The EPS matrix is considered as the “house of biofilm cells”, attributable to the scaffold of the three-dimensional (3D) polymer networks accounting for more than 90% of biofilms. Functionally, EPS provides mechanical stability to the biofilms and protects the microorganisms from desiccation. It also acts as a barrier against adverse chemical and biological influences, such as osmotic stress, acid and/or base challenges, oxygen, antibiotics, antiseptics, host immune defense, and grazing protozoa. Moreover, it contributes to the sorption and storage of nutrients and trace elements as the location of numerous extracellular enzymatic reactions, and keeps the microorganisms in tight contact with each other to facilitate the genetic exchange and bacterial communication. As such, EPS production is considered as an important adaptation for microorganisms to their living environments. Owing to their biocompatibility, non-toxicity, flexibility, biodegradability, and possibility to be recycled by biological processes, EPS is a promising platform for biotechnological, biomedical applications and therapeutic applications. Therefore, quantitative analysis the EPS produced by various microorganisms and monitoring the dynamic changes of EPS production are crucial to tailor their characteristics and optimize the amount of EPS produced. Numerous analytical techniques have been developed to characterize the components and spatial distribution of EPS, including Fourier transform infrared spectroscopy (FTIR), three-dimensional excitation-emission matrix fluorescence spectroscopy (3D-EEM), nuclear magnetic resonance spectroscopy (NMR), scanning electron microscopy (SEM), environmental scanning electron microscopy (ESEM), confocal laser scanning microscopy (CLSM), and atomic force microscopy (AFM). Among these methods, CLSM allows the in-situ and non-destructive visualization and quantification of the 3D structures of living and fully hydrated biofilms. A fluorescence labeling approach depends on the specificity of the selected stains, and multiple color staining technique and CLSM can together visualize the distribution of components of EPS in a biofilm. However, there is currently no fluorescence labeling method available for visualizing the EPS in general due to the highly complex and variable composition of the matrix produced by different microorganisms, their contrast spatial distribution patterns and highly dynamic properties. The conventional organic luminophores generally exhibit low resistance to photobleaching under strong laser irradiation, making these probes not suitable for long-term monitoring of EPS. In addition, they have small Stokes shift, resulting in strong self-absorption and low resolution, which makes them difficult for the real-time monitoring of the dynamic changes of EPS. Thus, development of novel fluorescent probes with improved properties for precise detection and long-term imaging is of great significance. In view of the foregoing, there is a continuing interest in developing a novel fluorescent probe for detecting and long-term monitoring EPS. SUMMARY The following presents a simplified summary of the disclosure in order to provide a basic understanding to the reader. This summary is not an extensive overview of the disclosure and it does not identify key/critical elements of the present invention or delineate the scope of the present invention. Its sole purpose is to present some concepts disclosed herein in a simplified form as a prelude to the more detailed description that is presented later. As embodied and broadly described herein, one aspect of the disclosure is directed to a core-shell nanoparticle having AIE properties. According to some embodiments of the present disclosure, the core-shell nanoparticle in structure comprises a core and a shell layer encapsulating the core, in which the core comprises a polymeric matrix and one or more tetraphenylethane (TPE) embedded in the polymeric matrix. According to some embodiments of the present disclosure, the polymeric matrix is made of a hydrophobic polymer. Preferably, the hydrophobic polymer is selecte