High sensitivity and label-free oligonucleotides detection using photonic bandgap sensing structures biofunctionalized with molecular beacon probes

Abstract

Abstract:A label-free sensor, based on the combination of silicon photonic bandgap (PBG) structures with immobilized molecular beacon (MB) probes, is experimentally developed. Complementary target oligonucleotides are specifically recognized through hybridization with the MB probes on the surface of the sensing structure. This combination of PBG sensing structures and MB probes demonstrates an extremely high sensitivity without the need for complex PCR-based amplification or labelling methods. correlates with morphological sub-class of acute myeloid leukaemia and the expression of its target genes in global genome-wide analysis," Leukemia 21(5), 912-916 (2007). 4. R. L. Maute, C. Schneider, P. Sumazin, A. Holmes, A. Califano, K. Basso, and R. Dalla-Favera, "tRNA-derived microRNA modulates proliferation and the DNA damage response and is down-regulated in B cell lymphoma," Proc. Natl. Acad. Sci. U.S.A. 110(4), 1404-1409 (2013). 5. L. P. Lim, N. C. Lau, P. Garrett-Engele, A. Grimson, J. M. Schelter, J. Castle, D. P. Bartel, P. S. Linsley, and J.M. Johnson, "Microarray analysis shows that some microRNAs downregulate large numbers of target mRNAs," Nature 433(7027), 769-773 (2005

Experimental study of the evanescent‐wave photonic sensors response in presence of molecular beacon conformational changes

“…Table shows the spectral shifts measured for both the target oligonucleotide detection experiment and the RI calibration cycle, while Figure shows the normalized oligonucleotide detection response of the PBG sensing structures when that absolute value of the shift in the calibration cycle was considered (normalized final PBG edge shifts are also indicated in Table ). Table also includes additional oligonucleotide detection results for other 2 identical PBG sensing structures biofunctionalized with streptavidin‐free MBs (MB 1* and MB 2*) obtained using a different chip in a different experiment . These results are included in order to overcome the problem of having only a single working PBG sensing structure biofunctionalized with the streptavidin‐free MB in the original experiment.…”

A Tetra-Panel of Serum Circulating miRNAs for the Diagnosis of the Four Most Prevalent Tumor Types

“…Taking all these premises into consideration, the H2020-SAPHELY project (https://saphely.eu) intends to break into the field of screening tests for early diagnosis of the four major cancer types, PCa, BC, LC, and CRC, by using a novel ultrahigh sensitivity nanophotonic-based sensing technique for the direct detection of circulating miRNA biomarkers through a combination of molecular beacon probes with an attached high index nanoparticle so that the hybridization events are translated into the displacement of these nanoparticles from the sensor surface [24,25]. The idea of the SAPHELY device because of the final cost of the test and the expected accuracy in cancer detection is that it could be useful in a cancer screening context.…”

Real Time Monitoring of a UV Light-Assisted Biofunctionalization Protocol Using a Nanophotonic Biosensor

“…In order to characterize the photonic chip, light from a continuous sweep tunable laser is coupled to the input grating couplers using a fiber collimator. Light coming out from the output grating couplers is measured using an infrared (IR) camera synchronized with the tunable laser in order to obtain the spectra of all the PBG sensing structures within the chip simultaneously [14]. The target solutions are flowed using a syringe pump working in withdraw mode and set to a constant flow rate of 10 μl/min to ensure laminar flow [15].…”