Detection of Marker miRNAs, Associated with Prostate Cancer, in Plasma Using SOI-NW Biosensor in Direct and Inversion Modes

Abstract

Information about the characteristics of measuring chips according to their storage conditions is of great importance for clinical diagnosis. In our present work, we have studied the capability of chips to detect nanowire biosensors when they are either freshly prepared or have been stored for either one or two years in a clean room. Potential to detect DNA oligonucleotides (oDNAs)—synthetic analogues of microRNAs (miRNAs) 198 and 429 that are associated with the development of prostate cancer (PCa)—in buffer solution was demonstrated using a nanowire biosensor based on silicon-on-insulator structures (SOI-NW biosensor). To provide biospecific detection, nanowire surfaces were sensitized with oligonucleotide probes (oDNA probes) complimentary to the known sequences of miRNA 183 and 484. In this study it is demonstrated that freshly prepared SOI-NW biosensor chips with n-type conductance and immobilized oDNA probes exhibit responses to the addition of complimentary oDNAs in buffer, leading to decreases in chips’ conductance at a concentration of 3.3 × 10−16 M. The influence of storage time on the characteristics of SOI-NW biosensor chips is also studied herein. It is shown that a two-year storage of the chips leads to significant changes in their characteristics, resulting in “inverse” sensitivity toward negatively charged oDNA probes (i.e., through an increase in chips’ conductance). It is concluded that the surface layer makes the main contribution to conductance of the biosensor chip. Our results indicate that the detection of target nucleic acid molecules can be carried out with high sensitivity using sensor chips after long-term storage, but that changes in their surface properties, which lead to inversed detection signals, must be taken into account. Examples of the applications of such chips for the detection of cancer-associated microRNAs in plasma samples of patients with diagnosed prostate cancer are given. The results obtained herein are useful for the development of highly sensitive nanowire-based diagnostic systems for the revelation of (prostate) cancer-associated microRNAs in human plasma.

Raman Spectroscopy-Based Quality Control of “Silicon-On-Insulator” Nanowire Chips for the Detection of Brain Cancer-Associated MicroRNA in Plasma

“…In our previous papers, we also demonstrated that the (nanowire biosensor)-based approach can be successfully employed for the detection of protein [ 32 , 43 , 44 , 49 ] and nucleic acid [ 41 , 42 , 50 ] biomolecules in plasma samples. Herein, the SOI-NW sensor chips with high-quality sensor chips has been demonstrated to be suitable for the highly sensitive detection (3.3 × 10 −17 M) of relatively small nucleic acid molecules in both purified buffer solutions and plasma samples.…”

Aptamer-Sensitized Nanoribbon Biosensor for Ovarian Cancer Marker Detection in Plasma

“…The use of biosensors with sensor elements of nanometer size-such as nanowires and nanoribbons-opens new horizons in biomedical research. These biosensors allow one to perform direct label-free detection of various targets-such as viral particles [6] and biological macromolecules (proteins [7][8][9][10][11][12][13] and nucleic acids [14][15][16][17][18][19])-in real time, attaining low (<1 fM, i.e., <10 −15 M) concentration detection limits [20]. The principle of operation of these biosensors consists of recording a modulation of an electric current, flowing through the sensor elements, in the course of binding of target particles (i.e., macromolecules or viral particles of interest) to their surface.…”

A Theoretical and Simulation Analysis of the Sensitivity of SiNWs-FET Sensors

“…Currently, thin film sensors and nanosensors are widely adopted for this mission because of their advantages in sensitivity [ 5 , 6 , 7 ]. Among these sensors, SiNWs-FET sensors have received increasing attention as they have ultrahigh sensitivity, which is necessary for the detection of these samples [ 8 , 9 , 10 , 11 ]. There are many factors, such as debye length [ 12 ], surface binding sites [ 13 ] and molecular affinities [ 14 ], that affect the sensitivity of SiNWs-FET sensors.…”