As an essential trace element in the human body, copper ion (Cu2+) performs an important role in many fundamental physiological processes that need a facile and effective method for the monitoring of Cu2+in organisms. Herein, a turn‐off, facile fluorescent strategy for sensing Cu2+was proposed using positively charged carbon dots (P‐CDs) as probe. The P‐CDs prepared from melting strategy exhibited stable, biocompatible, and pH‐sensitive luminescent properties. P‐CDs can be selectively quenched by Cu2+for the direct detection of Cu2+. The reaction mechanism between Cu2+and P‐CDs was systematically investigated, illustrating that Cu2+coordinated with the surface functional groups in P‐CDs. The binding effect of Cu2+and P‐CDs caused the constant morphology and static quenching behavior of P‐CDs. The promising accuracy of the testing results of the addition of Cu2+in diluted serum using P‐CDs implied their extended application in the biological field.
Detection of analytes by means of field-effect transistors bearing ligand-specific receptors is fundamentally limited by the shielding created by the electrical double layer (the “Debye length” limitation). We detected small molecules under physiological high–ionic strength conditions by modifying printed ultrathin metal-oxide field-effect transistor arrays with deoxyribonucleotide aptamers selected to bind their targets adaptively. Target-induced conformational changes of negatively charged aptamer phosphodiester backbones in close proximity to semiconductor channels gated conductance in physiological buffers, resulting in highly sensitive detection. Sensing of charged and electroneutral targets (serotonin, dopamine, glucose, and sphingosine-1-phosphate) was enabled by specifically isolated aptameric stem-loop receptors.
more » « less- Award ID(s):
- 1636136
- NSF-PAR ID:
- 10077548
- Publisher / Repository:
- American Association for the Advancement of Science (AAAS)
- Date Published:
- Journal Name:
- Science
- Volume:
- 362
- Issue:
- 6412
- ISSN:
- 0036-8075
- Page Range / eLocation ID:
- 319 to 324
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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