Direct determination of small RNAs using a biotinylated polythiophene impedimetric genosensor.
Herein, direct determination of small RNAs is described using a functional-polymer modified genosensor. The analytical strategy adopted involves deposition by electropolymerization of biotinylated polythiophene films on the surface of miniaturized, disposable, gold screen-printed electrodes, followed by the layer-by-layer deposition of streptavidin, and then biotynilated capture probes. A small RNA (miR-221) target was determined via the impedimetric measurement of the hybridization event in a label-free and PCR-free approach. Under optimized conditions, the limit of detection (LOD) was 0.7 pM miR-221 (15% RSD). The genosensor was applied for determination of miR-221 in total RNA extracted from human lung and breast cancer cell lines, discriminating between the cancer-positive and -negative cells, without any amplification step, in less than 2h.
Dipartimento di Chimica, Università degli Studi di Firenze, Via della Lastruccia 3, 50019 Sesto Fiorentino, Italy.
Diego
D
Voccia
Department of Physical Chemistry of Supramolecular Complexes, Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224, Warsaw, Poland.
Marta
M
Sosnowska
Dipartimento di Chimica, Università degli Studi di Firenze, Via della Lastruccia 3, 50019 Sesto Fiorentino, Italy.
Francesca
F
Bettazzi
Istituto di Endocrinologia e Oncologia Sperimentale, CNR, 80138 Napoli, Italy; Dipartimento di Medicina Molecolare e Biotecnologie Mediche, Università degli Studi di Napoli Federico II, Napoli, Italy.
Giuseppina
G
Roscigno
Dipartimento di Chimica, Università degli Studi di Firenze, Via della Lastruccia 3, 50019 Sesto Fiorentino, Italy.
Emiliano
E
Fratini
Istituto di Endocrinologia e Oncologia Sperimentale, CNR, 80138 Napoli, Italy.
Vittorio
V
De Franciscis
Istituto di Endocrinologia e Oncologia Sperimentale, CNR, 80138 Napoli, Italy; Dipartimento di Medicina Molecolare e Biotecnologie Mediche, Università degli Studi di Napoli Federico II, Napoli, Italy.
Gerolama
G
Condorelli
Chemistry Department, Central University of Rajasthan, Kishangarh, Rajasthan, India.
Raghu
R
Chitta
Department of Chemistry, University of North Texas, 1155, Union Circle, 305070 Denton, TX, United States.
Francis
F
D'Souza
Department of Physical Chemistry of Supramolecular Complexes, Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224, Warsaw, Poland; Faculty of Mathematics and Natural Sciences, School of Sciences, Cardinal Stefan Wyszynski University in Warsaw, Wóycickiego 1/3, 01-815 Warsaw, Poland.
Wlodzimierz
W
Kutner
Dipartimento di Chimica, Università degli Studi di Firenze, Via della Lastruccia 3, 50019 Sesto Fiorentino, Italy. Electronic address: ilaria.palchetti@unifi.it.
Ilaria
I
Palchetti
D015374:Biosensing Techniques / Q000379:methods*; D019921:Biotinylation; D045744:Cell Line, Tumor; D058266:Dielectric Spectroscopy / Q000379:methods*; D006801:Humans; D057230:Limit of Detection; D035683:MicroRNAs / Q000032:analysis* / Q000235:genetics; D009369:Neoplasms / Q000235:genetics; D011108:Polymers / Q000737:chemistry*; D013876:Thiophenes / Q000737:chemistry*
D035683:MicroRNAs; D011108:Polymers; D013876:Thiophenes; C525709:MIR221, human; C066730:polythiophene
2′-bithien-5-yl)methane; Bis(2; Electrochemical impedance spectroscopy; Genosensor; Small RNA; microRNA