TY  - JOUR
A1  - Cywinski, Piotr J.
A1  - Moro, Artur J.
A1  - Löhmannsröben, Hans-Gerd
T1  - Cyclic GMP recognition using ratiometric QD-fluorophore conjugate nanosensors
JF  - Biosensors and bioelectronics : the principal international journal devoted to research, design development and application of biosensors and bioelectronics
KW  - Quantum dots
KW  - Naphthyridines
KW  - Cyclic GMP
KW  - Base pairing
KW  - Fluorescent nanoconjugate
KW  - Nanosensor
Y1  - 2014
U6  - https://doi.org/10.1016/j.bios.2013.09.002
SN  - 0956-5663
SN  - 1873-4235
VL  - 52
SP  - 288
EP  - 292
PB  - Elsevier
CY  - Oxford
ER  - 
TY  - JOUR
A1  - Cywinski, Piotr J.
A1  - Moro, Artur J.
A1  - Ritschel, Thomas
A1  - Hildebrandt, Niko
A1  - Löhmannsröben, Hans-Gerd
T1  - Sensitive and selective fluorescence detection of guanosine nucleotides by nanoparticles conjugated with a naphthyridine receptor
JF  - Analytical & bioanalytical chemistry
N2  - Novel fluorescent nanosensors, based on a naphthyridine receptor, have been developed for the detection of guanosine nucleotides, and both their sensitivity and selectivity to various nucleotides were evaluated. The nanosensors were constructed from polystyrene nanoparticles functionalized by (N-(7-((3-aminophenyl) ethynyl)-1,8-naphthyridin- 2-yl) acetamide) via carbodiimide ester activation. We show that this naphthyridine nanosensor binds guanosine nucleotides preferentially over adenine, cytosine, and thymidine nucleotides. Upon interaction with nucleotides, the fluorescence of the nanosensor is gradually quenched yielding Stern-Volmer constants in the range of 2.1 to 35.9mM(-1). For all the studied quenchers, limits of detection (LOD) and tolerance levels for the nanosensors were also determined. The lowest (3 sigma) LOD was found for guanosine 3',5'-cyclic monophosphate (cGMP) and it was as low as 150 ng/ml. In addition, we demonstrated that the spatial arrangement of bound analytes on the nanosensors' surfaces is what is responsible for their selectivity to different guanosine nucleotides. We found a correlation between the changes of the fluorescence signal and the number of phosphate groups of a nucleotide. Results of molecular modeling and zeta-potential measurements confirm that the arrangement of analytes on the surface provides for the selectivity of the nanosensors. These fluorescent nanosensors have the potential to be applied in multi-analyte, array-based detection platforms, as well as in multiplexed microfluidic systems.
KW  - Naphthyridine receptor
KW  - cGMP
KW  - Base pairing
KW  - Nucleotide nanosensor
KW  - Fluorescence spectroscopy
Y1  - 2011
U6  - https://doi.org/10.1007/s00216-010-4420-2
SN  - 1618-2642
VL  - 399
IS  - 3
SP  - 1215
EP  - 1222
PB  - Springer
CY  - Heidelberg
ER  - 
TY  - JOUR
A1  - Idzik, Krzysztof Ryszard
A1  - Cywinski, Piotr J.
A1  - Cranfield, Charles G.
A1  - Mohr, Gerhard J.
A1  - Beckert, Rainer
T1  - Molecular recognition of the antiretroviral drug abacavir towards the development of a novel carbazole-based fluorosensor
JF  - Journal of fluorescence
N2  - Due to their optical and electro-conductive attributes, carbazole derivatives are interesting materials for a large range of biosensor applications. In this study, we present the synthesis routes and fluorescence evaluation of newly designed carbazole fluorosensors that, by modification with uracil, have a special affinity for antiretroviral drugs via either Watson-Crick or Hoogsteen base pairing. To an N-octylcarbazole-uracil compound, four different groups were attached, namely thiophene, furane, ethylenedioxythiophene, and another uracil; yielding four different derivatives. Photophysical properties of these newly obtained derivatives are described, as are their interactions with the reverse transcriptase inhibitors such as abacavir, zidovudine, lamivudine and didanosine. The influence of each analyte on biosensor fluorescence was assessed on the basis of the Stern-Volmer equation and represented by Stern-Volmer constants. Consequently we have demonstrated that these structures based on carbazole, with a uracil group, may be successfully incorporated into alternative carbazole derivatives to form biosensors for the molecular recognition of antiretroviral drugs.
KW  - HIV
KW  - HAART
KW  - Antiretroviral drugs
KW  - Carbazole
KW  - Base pairing
KW  - Fluorescence spectroscopy
Y1  - 2011
U6  - https://doi.org/10.1007/s10895-010-0798-7
SN  - 1053-0509
SN  - 1573-4994
VL  - 21
IS  - 3
SP  - 1195
EP  - 1204
PB  - Springer
CY  - New York
ER  -