A New Covalent Organic Framework of Dicyandiamide-Benzaldehyde Nanocatalytic Amplification SERS/RRS Aptamer Assay for Ultratrace Oxytetracycline with the Nanogold Indicator Reaction of Polyethylene Glycol 600

Abstract

In this paper, dicyandiamide (Dd) and p-benzaldehyde (Bd) were heated at 180 °C for 3 h to prepare a new type of stable covalent organic framework (COF) DdBd nanosol with high catalysis. It was characterized by molecular spectroscopy and electron microscopy. The study found that DdBd had a strong catalytic effect on the new indicator reaction of polyethylene glycol 600 (PEG600)-chloroauric acid to form gold nanoparticles (AuNPs). AuNPs have strong resonance Rayleigh scattering (RRS) activity, and in the presence of Victoria Blue B (VBB) molecular probes, they also have a strong surface-enhanced Raman scattering (SERS) effect. Combined with a highly selective oxytetracycline (OTC) aptamer (Apt) reaction, new dual-mode scattering SERS/RRS methods were developed to quantitatively analyze ultratrace OTC. The linear range of RRS is 3.00 × 10−3 –6.00 × 10−2 nmol/L, the detection limit is 1.1 × 10−3 nmol/L, the linear range of SERS is 3.00 × 10−3–7.00 × 10−2 nmol/L, and the detection limit is 9.0 × 10−4 nmol/L. Using the SERS method to analyze OTC in soil samples, the relative standard deviation is 1.35–4.78%, and the recovery rate is 94.3–104.9%.

MXene catalytic amplification-fluorescence/absorption dimode aptamer sensor for the detection of trace Pb2+ in milk

“…Resonance Rayleigh scattering ( 25 , 26 ) was a simple and sensitive molecular spectroscopy to study nanoparticles, and Abs spectrometry was a simple and low-cost spectral technique. We investigated the properties of MXenes using these two spectroscopic techniques.…”

State-of-the-Art Biosensors in China

“…Table shows the comparison between these main probe-based sensing techniques. Submillimeter [36,48,53] Millimeter [42][43][44][45][46][49][50][51]54] Centimeter [8,37,52] Thyroidectomy [42] Gastric Endomicroscopy [43] Hard-inclusion Localization [44] Optical biopsy [45] In vivo pressure sensor [46] Blood pressure [36 Implantable electrode [28][29][30]33] Optical fiber [31,32] 0.005-0.03 mm [33] Submillimeter [28,31,32] Millimeter [29,30] Blood glucose detection [28-31] Urinary protein detection [32] Cancer biomarker H 2 O 2 detection [33] are many kinds of force sensors, including but not limited to FBG-based sensors, triboelectric nanogenerators, capacitive sensors, piezoresistive sensors, and strain gauges.…”

“…Hou et al developed a biocompatible piezoresistive triaxial force sensor chip, which was integrated into the grip of a continuum robot to sense the grasping force of the MIS [49]. Yu et al presented surgical forceps that consisted of double grippers with 3D pulling and grasp force sensing, and a simple structure with a double E-type strain beam was used as the substrate to minimize the size of the robot [50,51]. The main principle of these force sensing devices was to transform the voltage changes in the strain gauges into the force with a mathematical model.…”

“…Here, an electrochemical sensor based on the COF Thi-TFPB [48][49][50][51] loaded with AChE for the detection of carbaryl is proposed. The positively charged COF Thi-TFPB can be easily stripped into two-dimensional nanosheets, and modified on the surface of a bare glassy carbon electrode (GCE) without adhesives or conductive agents.…”

Biosensor Based on Covalent Organic Framework Immobilized Acetylcholinesterase for Ratiometric Detection of Carbaryl

“…Here, an electrochemical sensor based on the COF Thi-TFPB [ 48 , 49 , 50 , 51 ] loaded with AChE for the detection of carbaryl is proposed. The positively charged COF Thi-TFPB can be easily stripped into two-dimensional nanosheets, and modified on the surface of a bare glassy carbon electrode (GCE) without adhesives or conductive agents.…”