Functional nanoprobes for ultrasensitive detection of biomolecules

Abstract

There has been great interest in developing new nucleic acid and protein detection methods for both clinical and numerous non-clinical applications. In a long-lasting effort to improve the detection ability of bioassays, functional nanomaterials have been actively explored to greatly enhance the sensitivity during the last two decades. This tutorial review focuses on recent progress in biosensor development by exploiting several unique optical, electronic and catalytic properties of a range of nanomaterials, such as gold nanoparticles, quantum dots, silicon nanowires, carbon nanotubes and graphene. In addition, a perspective on new opportunities offered by emerging technologies (e.g. DNA nanotechnology) is provided.

Parallel Polyadenine Duplex Formation at Low pH Facilitates DNA Conjugation onto Gold Nanoparticles

“…Adenine (pKa = 3.5) can be protonated at pH 3.0, which decreases the negative charge density on DNA and facilitates DNA adsorption. 4 However, this simple charge model cannot account for all the observations. 1) Based on the saltaging model, DNA should first lie down on AuNPs since DNA bases can also bind to gold strongly.…”

“…The interaction between DNA and gold nanoparticles (AuNPs) is an interesting biointerface topic with applications in analytical chemistry, [1][2][3][4][5][6] drug delivery, 7,8 and materials science. [9][10][11][12] AuNPs have a strong inter-particle van der Waals force, and citrate-capped AuNPs are only stabilized by weak electrostatic repulsion, rendering them easily aggregated at a slightly elevated ionic strength.…”

DNA Adsorption by Indium Tin Oxide Nanoparticles

“…These hybrid materials combine the molecular recognition and programmable property of DNA with the physical properties of inorganic nanoparticles, showing promising applications in many fields including biosensing, [1][2][3][4][5] drug delivery, 6 materials science, [7][8] and nanotechnology. [9][10][11][12] Over the past two decades, many nanomaterials, such as metallic nanoparticles, 13 semiconductor quantum dots, 14 and nanoscale carbon materials (e.g.…”

Carbon nanomaterials field-effect-transistor-based biosensors

“…2,3 In particular, researchers around the world have been tailor-making a multitude of nanomaterials-based electrical biosensors and developing new strategies to apply them in ultrasensitive biosensing. Examples of such nanomaterials include carbon nanotubes, [4][5][6][7][8][9][10][11][12][13] nanowires, 11,[14][15][16][17][18][19][20][21] nanoparticles, 6,[22][23][24][25] nanopores, 26,27 nanoclusters 28 and graphene. 5,[29][30][31][32] Compared with conventional optical, biochemical and biophysical methods, nanomaterial-based electronic biosensing offers significant advantages, such as high sensitivity and new sensing mechanisms, high spatial resolution for localized detection, facile integration with standard wafer-scale semiconductor processing and label-free, real-time detection in a nondestructive manner.…”