A new application of mesoporous carbon microparticles to nucleic acid detection

Abstract

Mesoporous carbon (MC) materials are important in many areas of technology, such as in storage of hydrogen and methane, supercapacitors, molecular separation, catalysis, etc. In this communication, we demonstrate the proof of concept of using MC microparticles as an effective fluorescent sensing platform for nucleic acid detection with a high selectivity down to single-base mismatch.During recent years, the detection of nucleic acid has been paid much attention due to their various applications in gene expression profiling, clinical disease diagnostics and treatment and thus the development of rapid, cost-effective, sensitive and specific detection methods is vitally important. 1 The increasing availability of nanostructures has created widespread interest in their use in biotechnological systems for diagnostic applications. 2 Indeed, a wealth of nanostructures have been successfully used for this purpose during recent years. 3 Homogeneous fluorescence assays based on fluorescence resonance energy transfer (FRET) or quenching mechanisms have recently been paid considerable attention for nucleic acid detection. 4 It is established that the selection issue of a fluorophore-quencher pair is eliminated from the assay if nanostructures are used as a quencher for a fluorophore because the same nanostructure is capable of quenching dyes of different emission frequencies. 4,5 So far, however, only very limited nanostructures including gold nanoparticles (AuNPs), single-walled carbon nanotubes (SWCNTs), and graphene have been demonstrated for such applications. 4-6 More recently, we have found that multiwalled carbon nanotubes (MWCNTs), carbon nanoparticles, and conjugation polymer nanostructures can also serve as effective fluorescent sensing platforms for this assay. 7 On the other hand, mesoporous carbon (MC) materials are important in many areas of technology, such as in storage of hydrogen and methane, supercapacitors, molecular separation, catalysis, etc. 8 The present communication demonstrates a novel application of MC to fluorescence-enhanced nucleic acid detection with the use of MC microparticles as an effective sensing platform for the first time. The nucleic detection is accomplished by the following steps: (1) MC adsorbs and quenches dye-labeled single-stranded DNA (ssDNA) probe; (2) the subsequent hybridization of the probe with its target produces a double-stranded DNA (dsDNA) which detaches from MC, leading to recovery of dye fluorescence. Most importantly, it suggests that this sensing platform is able to differentiate perfect complementary and mismatched targets with a high selectivity down to single-base mismatch. Fig. 1a shows the SEM image of MC particles. It is clearly seen that the MC products consist of a large amount of NPs. A local view of one single particle (inset) further indicates the MC particle is a microparticle with a length of 400 nm and a width of 200 nm. Fig. 1b shows the small angle X-ray diffraction (XRD) pattern of the MC microparticles. Three diffraction peaks were observed at 1...

Molecular Beacon Lighting up on Graphene Oxide

“…carbon nanotubes and graphene oxide). [20][21][22][23][24][25][26] Graphene is a single layer of graphite with many superior electronic and mechanical properties. [27][28][29][30] By generating surface hydroxyl and carboxyl groups, the resulting graphene oxide (GO) can disperse in water.…”

DNA‐Length‐Dependent Fluorescence Signaling on Graphene Oxide Surface

“…(2012 Submitted to -2 -process, the fluorophore-to-GO distance increased from zero to infinity to achieve the maximal fluorescence enhancement. In addition to GO, many other carbon based nanomaterials including carbon nanotubes, [25][26][27][28][29] mesoporous carbon, [30] carbon nanoparticles [31,32] and water soluble nano-C60 [33] have also been tested for similar applications.On the other hand, little is known about DNA length-dependent fluorescence quenching within a few nanometers from the GO surface. Such information is important for rational design of covalently linked probes.…”

Mesoporous carbon microparticles as a novel fluorescent sensing platform for thrombin detection

“…It is also of importance to note that the use of 12 L MCMPs can give a maximal fluorescence quenching efficiency and thus an optimal volume of 12 L was chosen in our present study. When TA molecules are mixed with MCMPs, TA will adsorb on the microparticles surface due to -stacking effects of DNA bases on -rich MCMP (Varghese et al, 2009;Liu et al, 2011) leading to substantial quenching of dye fluorescence due to their very close proximity (McCreey, 2008;Yang et al, 2004). We have found that the adding of MCMPs into fluorescein solution only leads to slight decrease of the fluorescence of fluorescein in intensity (Fig.…”

“…The mesoporous nature of these microparticles was confirmed by the corresponding XRD and nitrogen adsorption-desorption isotherm analysis. These MCMPs have uniform pore structure and narrow pore size distribution around 4.0 nm (Liu et al, 2011). The performance of this MCMP-based aptasensor for TB detection was studied in the following fluorescence experiments.…”

“…(Wang et al, 2005;Liang et al, 2008;Meng et al, 2005). More recently, we have demonstrated that MC microparticles (MCMPs) can be used for fluorescence-enhanced nucleic acid detection (Liu et al, 2011). In this paper, we further demonstrate the development of a novel fluorescent aptasensor for TB detection with the use of MCMPs as an effective sensing platform.…”