Novel superparamagnetic core-shell imprinting microspheres (MCSIMs) were synthesized using magnetite microspheres with 350 nm diameter and 70 nm thickness silica gel to form core-shell Fe(3)O(4)/SiO(2) composite for template phenylephrine (Phen) recognition and high efficiency separation. Compared to the previous imprinting recognition, the main advantage of this strategy lies in two aspects: one is the high stability and monodispersity of the MCSIMs structure, the other is the use of superparamagnetic Fe(3)O(4)/SiO(2) microspheres as an immobilization matrix and separation tool, thus greatly simplifying time-consuming washing steps. The affinity and selectivity of the MCSIMs were monitored by QCM and electrochemistry measurements. Imprinting microspheres have a remarkable affinity to Phen over that of structurally related molecules, including DA, EP, Phe and Tyr. The relative binding selectivity for different analytes estimated from amperometric signals was Phen : DA : EP = 40 : 5 : 1. The MCSIMs sensor showed a high sensitivity (400 microA mM(-1)), short response time (reaching 98% within 10 s), and broad linear response range from 1 microM to 0.1 mM and low detection limit (0.1 microM). Additionally, the results of control experiments showed that only negligible signal was obtained for non-imprinting microspheres. This could be reasonably attributed to the unique surface pores, charges and especially the nature of the functional groups inside MCSIMs cavities.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1039/b802120a | DOI Listing |
Lab Chip
January 2025
Department of Food Science and Agricultural Chemistry, McGill University Macdonald Campus, Sainte-Anne-de-Bellevue, Quebec, H9X 3V9, Canada.
Mycotoxins are detectable in 60-80% of food crops, posing significant threats to human health and food security, and causing substantial economic losses. Most mitigation approaches focus on detecting mycotoxins with standard methods based on liquid chromatography coupled with mass spectrometry (LC-MS). Typical MS methods require extensive sample preparation and clean-up due to the matrix effect, followed by time-consuming LC separation, complicating the analysis process and limiting analytical throughput.
View Article and Find Full Text PDFPolymers (Basel)
November 2024
Shandong Key Laboratory of Healthy Food Resources Exploration and Creation, School of Food Science and Engineering, Qilu University of Technology (Shandong Academy of Sciences), Jinan 250353, China.
The development of fluorescent sensors with high sensitivity and fast response times is attracting the interest of more and more researchers. Herein, dual-emission ratiometric molecularly imprinted fluorescent encoded microspheres were fabricated and applied for the fast detection of norfloxacin. Core-shell-structured imprinted polymers with ZIF-8 as the supporting core were obtained first and two quantum dots with green and red emission provided the fluorescent signal.
View Article and Find Full Text PDFMacromol Rapid Commun
November 2024
Physico-chimie des Électrolytes et Nanosystèmes Interfaciaux, PHENIX, Sorbonne Université CNRS, Paris, F-75005, France.
Herein, a photoinduced method is introduced for the synthesis of highly cross-linked and uniform polymer microspheres by atom transfer radical polymerization (ATRP) at room temperature and in the absence of stabilizers or surfactants. Uniform particles are obtained at monomer concentrations as high as 10% (by volume), with polymers being exempt from contamination by residual transition metal catalysts, thereby overcoming the two major longstanding problems associated with thermally initiated ATRP-mediated precipitation polymerization. Moreover, the obtained particles have also immobilized ATRP initiators on their surface, which directly enables the controlled growth of densely grafted polymer layers with adjustable thickness and a well-defined chemical composition.
View Article and Find Full Text PDFJ Nanobiotechnology
November 2024
College of Chemistry and Chemical Engineering, Institute of Biomedical Materials and Engineering, College of Materials Science and Engineering, Qingdao University, Qingdao, 266071, Shandong, China.
Background: The production of β-lactamases is the most prevalent resistance mechanism for β-lactam antibiotics in Gram-negative bacteria. Presently, over 4900 β-lactamases have been discovered, and they are categorized into hundreds of families. In each enzyme family, amino acid substitutions result in subtle changes to enzyme hydrolysis profiles; in contrast, certain conserved sequences retained by all of the family members can serve as important markers for enzyme family identification.
View Article and Find Full Text PDFInt J Biol Macromol
November 2024
The College of Forestry, Beijing Forestry University, 100083 Beijing, PR China; State Key Laboratory of Efficient Production of Forest Resources, Beijing Forestry University, 100083 Beijing, PR China; Ecological Observation and Research Station of Heilongjiang Sanjiang Plain Wetlands, National Forestry and Grassland Administration, 155100 Shuangyashan, PR China; The College of Biological Sciences and Technology, Beijing Forestry University, 100083 Beijing, PR China. Electronic address:
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!