PEGylated Ni Single-Atom Catalysts as Ultrasensitive Electrochemiluminescent Probes with Favorable Aqueous Dispersibility for Assaying Drug-Resistant Pathogens.
Yuchan MaYu ZhangJiaqi GaoHui OuyangYong HeZhifeng FuPublished in: Analytical chemistry (2022)
Ni single-atom catalysts (SACs) were synthesized by high-temperature calcination of nickel ions and 1,10-phenanthroline on carbon black as a carrier. Benefiting from the ultrahigh atom utilization efficiency, Ni SACs can significantly accelerate decay of dissolved oxygen to generate abundant reactive oxygen species through an oxygen reduction reaction occurring on cathodes. The generated reactive oxygen species can vastly enhance the electrochemiluminescent (ECL) signal of luminol without participation of exogenous co-reactants. To overcome the inherent unfavorable aqueous dispersibility of Ni SACs prepared by the calcination protocol, they were functionalized with highly hydrophilic PEG 2000. Thanks to the abundant carboxyl groups on PEG 2000, the PEGylated Ni SACs (Ni@PEG) can be used as ECL probes to tag biorecognition molecules. In this proof-of-principle work, an ECL biosensor for assaying methicillin-resistant <i>Staphylococcus aureus</i> was developed by using porcine IgG as capture molecule and phage cell-binding domain tagged with Ni@PEG as signal tracer. It shows a broad linear range of 73-7.3 × 10<sup>6</sup> CFU/mL and a low detection limit of 25 CFU/mL. The recovery values for assaying spiked samples are between 80.8 and 119.2%. It was also utilized to assess MRSA susceptibility to four antibiotics, with results consistent with those obtained by the standard broth microdilution technique. To the best of our knowledge, it is the first time to utilize aqueous dispersible SACs as highly sensitive ECL probes for developing biosensors.
Keyphrases
- metal organic framework
- staphylococcus aureus
- transition metal
- drug resistant
- reactive oxygen species
- small molecule
- drug delivery
- quantum dots
- label free
- multidrug resistant
- molecular dynamics
- living cells
- gold nanoparticles
- randomized controlled trial
- methicillin resistant staphylococcus aureus
- healthcare
- ionic liquid
- pseudomonas aeruginosa
- high temperature
- fluorescence imaging
- acinetobacter baumannii
- single cell
- physical activity
- biofilm formation
- molecularly imprinted
- fluorescent probe
- liquid chromatography
- mass spectrometry
- gram negative
- electron transfer
- transcription factor
- escherichia coli
- positron emission tomography
- neural network
- dna binding
- pet imaging