A nanocomposite optosensor containing carboxylic functionalized multiwall carbon nanotubes and quantum dots incorporated into a molecularly imprinted polymer for highly selective and sensitive detection of ciprofloxacin

Abstract

A nanocomposite optosensor consisting of carboxylic acid functionalized multiwall carbon nanotubes and CdTe quantum dots embedded inside a molecularly imprinted polymer (COOH@MWCNT-MIP-QDs) was developed for trace ciprofloxacin detection. The COOH@MWCNT-MIP-QDs were synthesized through a facile sol-gel process using ciprofloxacin as a template molecule, 3-aminopropylethoxysilane as a functional monomer and tetraethoxysilane as a cross-linker at a molar ratio of 1:8:20. The synthesized nanocomposite optosensor had high sensitivity, excellent specificity and high binding affinity to ciprofloxacin. Under optimal conditions, the fluorescence intensity of the optosensor decreased in a linear fashion with the concentration of ciprofloxacin and two linear dynamic ranges were obtained, 0.10-1.0 μg L and 1.0-100.0 μg L with a very low limit of detection of 0.066 μg L. The imprinting factors of the two linear range were 17.67 and 4.28, respectively. The developed nanocomposite fluorescence probe was applied towards the determination of ciprofloxacin levels in chicken muscle and milk samples with satisfactory recoveries being obtained in the range of 82.6 to 98.4%. The results were also in good agreement with a HPLC method which indicates that the optosensor can be used as a sensitive, selective and rapid method to detect ciprofloxacin in chicken and milk samples.

Synthesis of CdTe Quantum Dots‐based Imprinting Fluorescent Nanosensor for Highly Specific and Sensitive Determination of Caffeic Acid in Apple Juices

“…Figure 5A indicates that fluorescence intensity increases with the increase in CdTe‐QDs@MIPs concentrations from 20 to 100 μg mL −1 , then provides no significant difference from 100 to 300 μg mL −1 , and the highest quenching efficiency is achieved with CdTe‐QDs@MIPs concentration at 100 μg mL −1 . Lower CdTe‐QDs@MIPs concentration results in lower fluorescence intensity and narrow linear range, whereas higher CdTe‐QDs@MIPs concentration reduces slight agglomeration and then results in low sensitivity [29]. Therefore, CdTe‐QDs@MIPs concentration has been optimized as 100 μg mL −1 .…”

Optical and Electrochemical Sensors and Biosensors for the Detection of Quinolones

“…The detection process was based on fluorescence quenching of QDs upon CIPR binding to the binding sites on the MIP part of developed nanocomposite. The method was highly sensitive and could detect low concentrations of CIPR in chicken muscle and milk (lower than the MRL values set by EU) [44].…”

“…(A) COOH@MWCNT-MIP-QDs nanocomposite for the detection of ciprofloxacin; (B) preparation of aptamer-MIP/UCNPs hybrid probe and enrofloxacin detection; (C) hybrid of aptamer-MNPs and UCNPs nanoprobes for the detection of enrofloxacin; (D) label-free fluorescent assay based on GO for the enrofloxacin detection. Reprinted from[5,28,44,47] with permission. Abbreviations: MWCNT, multi-walled carbon nanotube; MIP, molecular imprinted polymer; QDs, quantum dots; UCNPs, upconversion nanoparticles; GO, graphene oxide.…”

Nanomaterials for Healthcare Biosensing Applications

“…Linearity was observed from 10.0 to 60.0 ng mL −1 in spiked human serum with an LOD of 3.6 ng mL −1 . Yupintharakun’s group developed an optosensor for the detection of ciprofloxacin, an antibiotic commonly used in the treatment of various ailments of the skin and kidneys, by employing a nanocomposite of CMWCNT, CdTe quantum dots, and molecularly imprinted APTES polymer [324]. The sensor showed high binding affinity and specificity, and exceptional sensitivity wherein the fluorescence intensity reduced in a linear fashion from 0.10 to 100.0 μg L −1 and the detection limit was found to be 66 ng L −1 .…”