Showing papers on "Deoxyribozyme published in 2014"
TL;DR: A DNA dendrimer scaffold is reported as an efficient nanocarrier to deliver FNAs and to conduct in situ monitoring of biological molecules in living cells and may find a broad spectrum of applications in biomedical diagnosis and therapy.
Abstract: Functional nucleic acid (FNA)-based sensing systems have been developed for efficient detection of a wide range of biorelated analytes by employing DNAzymes or aptamers as recognition units. However, their intracellular delivery has always been a concern, mainly in delivery efficiency, kinetics, and the amount of delivered FNAs. Here we report a DNA dendrimer scaffold as an efficient nanocarrier to deliver FNAs and to conduct in situ monitoring of biological molecules in living cells. A histidine-dependent DNAzyme and an anti-ATP aptamer were chosen separately as the model FNAs to make the FNA dendrimer. The FNA-embedded DNA dendrimers maintained the catalytic activity of the DNAzyme or the aptamer recognition function toward ATP in the cellular environment, with no change in sensitivity or specificity. Moreover, these DNA dendrimeric nanocarriers show excellent biocompatibility, high intracellular delivery efficiency, and sufficient stability in a cellular environment. This FNA dendrimeric nanocarrier ma...
144 citations
TL;DR: The amplified, highly sensitive detection of DNA using the dendritic rolling circle amplification (RCA) is introduced and the hemin/G-quadruplex horseradish peroxidase (HRP)-mimicking DNAzyme as catalytic labels that provide colorimetric or chemiluminescent readout signals are implemented.
Abstract: The amplified, highly sensitive detection of DNA using the dendritic rolling circle amplification (RCA) is introduced. The analytical platform includes a circular DNA and a structurally tailored hairpin structure. The circular nucleic acid template includes a recognition sequence for the analyte DNA (the Tay-Sachs mutant gene), a complementary sequence to the Mg2+-dependent DNAzyme, and a sequence identical to the loop region of the coadded hairpin structure. The functional hairpin in the system consists of the analyte-sequence that is caged in the stem region and a single-stranded loop domain that communicates with the RCA product. The analyte activates the RCA process, leading to DNA chains consisting of the Mg2+-dependent DNAzyme and sequences that are complementary to the loop of the functional hairpin structure. Opening of the coadded hairpin releases the caged analyte sequence, resulting in the dendritic RCA-induced synthesis of the Mg2+-dependent DNAzyme units. The DNAzyme-catalyzed cleavage of a f...
121 citations
TL;DR: This method exhibited a high sensitivity toward target DNA with a detection limit of 8 fM, which was about 100 times lower than that of the reported DNAzyme-based colorimetric system for DNA detection with Exo III-assisted cascade signal amplification.
Abstract: Detection of ultralow concentrations of specific nucleic acid sequences is a central challenge in the early diagnosis of genetic diseases and biodefense applications. Herein, we report a simple and homogeneous chemiluminescence (CL) method for ultrasensitive DNA detection. It is based on the exonuclease III (Exo III)-assisted cascade signal amplification and the catalytic effect of G-quadruplex-hemin DNAzyme on the luminol-H2O2 CL system. A quadruplex-forming DNA probe hybridizes a hairpin DNA probe to construct a duplex DNA probe as recognition element. Upon sensing of target DNA, the recognition of target DNA and the duplex DNA probe triggers the Exo III cleavage process, accompanied by releasing target DNA and generating a new secondary target DNA fragment. The released target DNA and the secondary target DNA are recycled. Simultaneously, numerous quadruplex-forming sequences are liberated and bind hemin to yield G-quadruplex-hemin DNAzyme, which subsequently catalyze the luminol-H2O2 reaction to produce strong CL emission. This method exhibited a high sensitivity toward target DNA with a detection limit of 8 fM, which was about 100 times lower than that of the reported DNAzyme-based colorimetric system for DNA detection with Exo III-assisted cascade signal amplification. This method provides a simple, isothermal, and low-cost approach for sensitive detection of DNA and holds a great potential for early diagnosis in gene-related diseases.
116 citations
TL;DR: This review describes how it is able to design and examine functional DNA switches, particularly those systems that utilize electrochemical signaling, and discusses different available options for labeling functional DNA with redox reporters, and comment on the function-oriented signaling pathways.
Abstract: Recent developments in nanoscience research have demonstrated that DNA switches (rationally designed DNA nanostructures) constitute a class of versatile building blocks for the fabrication and assembly of electronic devices and sensors at the nanoscale. Functional DNA sequences and structures such as aptamers, DNAzymes, G-quadruplexes, and i-motifs can be readily prepared in vitro, and subsequently adapted to an electrochemical platform by coupling with redox reporters. The conformational or conduction switching of such electrode-bound DNA modules in response to an external stimulus can then be monitored by conventional voltammetric measurements. In this review, we describe how we are able to design and examine functional DNA switches, particularly those systems that utilize electrochemical signaling. We also discuss different available options for labeling functional DNA with redox reporters, and comment on the function-oriented signaling pathways.
103 citations
TL;DR: Experimental results demonstrate that the electrochemical method proposed can detect as low as 1 pM breast cancer gene BRCA1 in a 10 μL sample volume without any signal amplification process or the involvement of other synthesized complex, which may provide an alternative for cancer DNA detection.
Abstract: Rational utilization of nanomaterials to construct electrochemical nucleic acid sensors has attracted large attention in recent years. In this work, we systematically interrogate the interaction between gold nanoparticles (GNPs) and single-strand DNA (ssDNA) immobilized on an electrode surface and then take advantage of the ultrahigh charge-transfer efficiency of GNPs to develop a novel DNA sensing method. Specifically, ssDNA modified gold electrode can adsorb GNPs because of the interaction between gold and nitrogen-containing bases; thus, the negative electrochemical species [Fe(CN)6](3-/4-) may transfer electrons to electrode through adsorbed GNPs. In the presence of target DNA, the formed double-strand DNA (dsDNA) cannot capture GNPs onto the electrode surface and the dsDNA may result in a large charge-transfer resistance owing to the negatively charged phosphate backbones of DNA. So a simple but sensitive method for the detection of target DNA can be developed by using GNPs without any requirement of modification. Experimental results demonstrate that the electrochemical method we have proposed in this work can detect as low as 1 pM breast cancer gene BRCA1 in a 10 μL sample volume without any signal amplification process or the involvement of other synthesized complex, which may provide an alternative for cancer DNA detection. This method may also be generalized for detecting a spectrum of targets using functional DNA (aptamer, metal-specific oligonucleotide, or DNAzyme) in the future.
94 citations
TL;DR: This assay exhibits several advantages such as simplicity, low-cost, high selectivity and desirable sensitivity, which shows great potential of providing a promising platform for convenient and visualized analysis of UDG or other biomolecules.
91 citations
TL;DR: A G-quadruplex DNAzyme-based DNA ligase sensor was developed, which eliminated the needs for any labeled oligonucleotide probes, thus making label-free detection possible and could be easily extended to the design of PNKP sensor.
88 citations
TL;DR: This review summarizes the development of functional nucleic acid-based sensors for the detection of Pb(2+), Hg(2+) and Ag(+), and especially focus on two categories including the direct assay and the amplification-based assay.
Abstract: Heavy metal contaminants such as lead ions (Pb2+), mercury ions (Hg2+) and silver ions (Ag+) can cause significant harm to humans and generate enduring bioaccumulation in ecological systems. Even though a variety of methods have been developed for Pb2+, Hg2+ and Ag+ assays, most of them are usually laborious and time-consuming with poor sensitivity. Due to their unique advantages of excellent catalytic properties and high affinity for heavy metal ions, functional nucleic acids such as DNAzymes and aptamers show great promise in the development of novel sensors for heavy metal ion assays. In this review, we summarize the development of functional nucleic acid-based sensors for the detection of Pb2+, Hg2+ and Ag+, and especially focus on two categories including the direct assay and the amplification-based assay. We highlight the emerging trends in the development of sensitive and selective sensors for heavy metal ion assays as well.
84 citations
TL;DR: In vitro selection of RNA-cleaving DNAzymes was carried out using a library containing a region of 35 random nucleotides in the presence of Lu (3+), since Lu(3+) was reported to be the most efficient lanthanide for RNA cleavage.
Abstract: Developing biosensors for lanthanides is an important but challenging analytical task. To address this problem, in vitro selection of RNA-cleaving DNAzymes was carried out using a library containing a region of 35 random nucleotides in the presence of Lu3+, since Lu3+ was reported to be the most efficient lanthanide for RNA cleavage. The resulting DNA sequences can be aligned to a single family with two conserved stretches of nucleotides. One of the representative DNAzymes (named Lu12) was further studied. Lu12 is more active with smaller lanthanides and has the lowest activity in the presence of the largest lanthanide (lutetium). Its cleavage rate is 0.12 min–1 in the presence of 10 μM Nd3+ at pH 6.0. This is a new DNAzyme, and a catalytic beacon sensor is designed by attaching a fluorophore/quencher pair, detecting Nd3+ down to 0.4 nM (72 parts-per-trillion). This DNAzyme is highly selective for lanthanides as well, showing cleavage only with two nonlanthanide ions: Y3+ and Pb2+. We previously reported ...
79 citations
TL;DR: An amplified colorimetric detection of Hg(2+) is proposed by combining T-Hg( 2+)-T base pairs and hybridization chain reaction (HCR), which enables the high sensitive and selective detection of aqueous Hg (2+) with a detection limit of 9.7 pM.
76 citations
TL;DR: A novel visual electrochemiluminescence analysis strategy for detection of telomerase activity is reported on a microarray chip, with G-quadruplex deoxyribozyme (DNAzyme) and luminol modified Au nanoparticles (NPs) as double-catalytic amplification labels.
TL;DR: A simple strategy based on methylation-blocked cascade amplification is developed for label-free colorimetric assay of MTase activity, and the inhibition of Dam MTase is well investigated, indicating great potential for the practicality in high concentrations of interfering species.
TL;DR: Preparative labeling under mild conditions for up to ~160-nt-long RNAs, including spliceosomal U6 small nuclear RNA and a cyclic-di-AMP binding riboswitch RNA is demonstrated.
Abstract: A general and efficient single-step method was established for site-specific post-transcriptional labeling of RNA. Using Tb(3+) as accelerating cofactor for deoxyribozymes, various labeled guanosines were site-specifically attached to 2'-OH groups of internal adenosines in in vitro transcribed RNA. The DNA-catalyzed 2',5'-phosphodiester bond formation proceeded efficiently with fluorescent, spin-labeled, biotinylated, or cross-linker-modified guanosine triphosphates. The sequence context of the labeling site was systematically analyzed by mutating the nucleotides flanking the targeted adenosine. Labeling of adenosines in a purine-rich environment showed the fastest reactions and highest yields. Overall, practically useful yields >70% were obtained for 13 out of 16 possible nucleotide (nt) combinations. Using this approach, we demonstrate preparative labeling under mild conditions for up to ~160-nt-long RNAs, including spliceosomal U6 small nuclear RNA and a cyclic-di-AMP binding riboswitch RNA.
TL;DR: Recent developments in integrating high selectivity of functional DNA, such as DNAzymes and aptamers, with efficient DNA delivery into cells by gold nanoparticles or superior near-infrared optical properties of upconversion nanoparticles are reviewed.
TL;DR: A biosensing system is established for the multi-amplified detection of DNA or specific substrates of aptamers under isothermal conditions, which combines nicked rolling circle amplification (N-RCA) and beacon assisted amplification (BAA) with sensitive colorimetric technique by using DNAzymes as reporter units, indicating an excellent selectivity of the proposed strategy.
TL;DR: Two different signals are used to follow the switchable functions (fluorescence and the catalytic functions of the derived hemin-G-quadruplex DNAzyme).
Abstract: Programmed nucleic acid sequences undergo K(+) ion-induced self-assembly into G-quadruplexes and separation of the supramolecular structures by the elimination of K(+) ions by crown ether or cryptand ion-receptors. This process allows the switchable formation and dissociation of the respective G-quadruplexes. The different G-quadruplex structures bind hemin, and the resulting hemin-G-quadruplex structures reveal horseradish peroxidase DNAzyme catalytic activities. The following K(+) ion/receptor switchable systems are described: 1) The K(+) -induced self-assembly of the Mg(2+) -dependent DNAzyme subunits into a catalytic nanostructure using the assembly of G-quadruplexes as bridging unit. 2) The K(+) -induced stabilization of the anti-thrombin G-quadruplex nanostructure that inhibits the hydrolytic functions of thrombin. 3) The K(+) -induced opening of DNA tweezers through the stabilization of G-quadruplexes on the "tweezers' arms" and the release of a strand bridging the tweezers into a closed structure. In all of the systems reversible, switchable, functions are demonstrated. For all systems two different signals are used to follow the switchable functions (fluorescence and the catalytic functions of the derived hemin-G-quadruplex DNAzyme).
TL;DR: The progressive development of amplified DNA sensors using nucleic acid-based machineries, involving the isothermal autonomous synthesis of the Mg(2+)-dependent DNAzyme, is used for the amplified, multiplexed analysis of genes and metal ions.
Abstract: The progressive development of amplified DNA sensors using nucleic acid-based machineries, involving the isothermal autonomous synthesis of the Mg2+-dependent DNAzyme, is used for the amplified, multiplexed analysis of genes (Smallpox, TP53) and metal ions (Ag+, Hg2+). The DNA sensing machineries are based on the assembly of two sensing modules consisting of two nucleic acid scaffolds that include recognition sites for the two genes and replication tracks that yield the nicking domains for Nt.BbvCI and two different Mg2+-dependent DNAzyme sequences. In the presence of any of the genes or the genes together, their binding to the respective recognition sequences triggers the nicking/polymerization machineries, leading to the synthesis of two different Mg2+-dependent DNAzyme sequences. The cleavage of two different fluorophore/quencher-modified substrates by the respective DNAzymes leads to the fluorescence of F1 and/or F2 as readout signals for the detection of the genes. The detection limits for analyzing ...
TL;DR: A self-reporting isothermal system for visual bacterial pathogen detection with single base resolution is developed and applied for the discrimination of Escherichia coli, Salmonella typhimurium, and Clostridium difficile genomes.
Abstract: We have developed a self-reporting isothermal system for visual bacterial pathogen detection with single base resolution. The new DNA diagnostic is based on combination of peptide nucleic acid (PNA) technology, rolling circle amplification (RCA) and DNAzymes. PNAs are used as exceedingly selective chemical tools that bind genomic DNA at a predetermined sequence under nondenaturing conditions. After assembly of the PNA-DNA construct a padlock probe is circularized on the free strand. The probe incorporates a G-quadruplex structure flanked by nicking enzyme recognition sites. The assembled circle serves as a template for a novel hybrid RCA strategy that allows for exponential amplification and production of short single-stranded DNA pieces. These DNA fragments fold into G-quadruplex structures and when complexed with hemin become functional DNAzymes. The catalytic activity of each DNAzyme unit leads to colorimetric detection and provides the second amplification step. The combination of PNA, RCA, and DNAzymes allows for sequence-specific and highly sensitive detection of bacteria with a colorimetric output observed with the naked eye. Herein, we apply this method for the discrimination of Escherichia coli, Salmonella typhimurium, and Clostridium difficile genomes.
TL;DR: In vitro selection and characterization of a new deoxyribozyme called F-8, which catalyzes nucleotide excision specifically at thymidine, and the results illustrate the potential of DNAzymes as tools for DNA manipulation.
Abstract: Single-nucleotide polymorphisms, either inherited or due to spontaneous DNA damage, are associated with numerous diseases. Developing tools for site-specific nucleotide modification may one day provide a way to alter disease polymorphisms. Here, we describe the in vitro selection and characterization of a new deoxyribozyme called F-8, which catalyzes nucleotide excision specifically at thymidine. Cleavage by F-8 generates 3'- and 5'-phosphate ends recognized by DNA modifying enzymes, which repair the targeted deoxyribonucleotide while maintaining the integrity of the rest of the sequence. These results illustrate the potential of DNAzymes as tools for DNA manipulation.
TL;DR: A dual strategy for sensitive detection of T4 polynucleotide kinase (T4 PNK) activity was proposed, which combined split DNAzyme-based background reduction with ligation-triggered DNAzyme cascade for signal amplification and inhibition effects of adenosine diphosphate and sodium hydrogen phosphate have been demonstrated with satisfactory results.
TL;DR: A universal "DNA-only Cascade" (DoC) is developed to quantitatively detect target analytes with increased speed and efficiently discriminates nucleic acid targets differing by a single nucleotide.
Abstract: Diagnostic tests performed in the field or at the site of patient care would benefit from using a combination of inexpensive, stable chemical reagents and simple instrumentation. Here, we have developed a universal “DNA-only Cascade” (DoC) to quantitatively detect target analytes with increased speed. The DoC utilizes quasi-circular structures consisting of temporarily inactivated deoxyribozymes (DNAzymes). The catalytic activity of the DNAzymes is restored in a universal manner in response to a broad range of environmental and biological targets. The present study demonstrates DNAzyme activation in the presence of metal ions (Pb2+), small molecules (deoxyadenosine triphosphate) and nucleic acids homologous to genes from Meningitis-causing bacteria. Furthermore, DoC efficiently discriminates nucleic acid targets differing by a single nucleotide. When detection of analytes is orchestrated by functional nucleic acids, the inclusion of DoC reagents substantially decreases time for detection and allows analyt...
TL;DR: By employing graphene together with a peroxidase-mimic DNAzyme, this work has developed a novel dual-colorimetric strategy for DNA detection that is able to detect the target DNA very easily and sensitively with the naked eye.
Abstract: In this work, by employing graphene together with a peroxidase-mimic DNAzyme, we have developed a novel dual-colorimetric strategy for DNA detection. In this strategy, a bi-functional probe DNA with both the sequence to have peroxidase activity and the sequence to be complementary to the target DNA is designed. Through π–π stacking, the probe DNA can interact with graphene; however, when the target DNA is present, the graphene-probe DNA interaction will be interrupted, resulting in the peroxidase activity being transferred from the precipitated graphene to the supernatant under centrifugation. Consequently, colorimetric signals can be obtained due to the catalytic reactions by the formed peroxidase-mimic DNAzyme. By observing the changes of the color depth of either the precipitate or the supernate, we are able to detect the target DNA very easily and sensitively with the naked eye. The dual colorimetric signals (signal-off for the precipitate and signal-on for the supernate) can also be integrated through mathematical operations, which may greatly improve the performance of the sensing platform.
TL;DR: The development of a new label-free, simple and sensitive colorimetric detection method for ATP by using un-modified aptamers and DNAzymes is described, which is highly selective toward ATP against other control molecules and can be performed in one single homogeneous solution, which makes the sensing approach hold great potential for sensitive colorIMetric detection of other small molecules and proteins.
TL;DR: The activation of such enzymatic cascades through analyte-DNAzyme interactions is not only valuable to activate the cooperation of enzyme networks, but also has a substantial impact on the development of amplified DNAzyme sensors.
TL;DR: A powerful new strategy for the fabrication of high-density RNA arrays is described, compatible with 2'-fluoro-modified (2'F) ribonucleoside triphosphates (rNTPs), which may be included in the polymerase extension reaction to impart nuclease resistance and other desirable characteristics to the synthesized RNAs.
Abstract: A powerful new strategy for the fabrication of high-density RNA arrays is described. A high-density DNA array is fabricated by standard photolithographic methods, the surface-bound DNA molecules are enzymatically copied into their RNA complements from a surface-bound RNA primer, and the DNA templates are enzymatically destroyed, leaving behind the desired RNA array. The strategy is compatible with 2′-fluoro-modified (2′F) ribonucleoside triphosphates (rNTPs), which may be included in the polymerase extension reaction to impart nuclease resistance and other desirable characteristics to the synthesized RNAs. The use and fidelity of the arrays are explored with DNA hybridization, DNAzyme cleavage, and nuclease digestion experiments.
TL;DR: Binding of 14 lanthanides to a lanthanide-dependent DNAzyme is studied, where the binding affinity is symmetric across the series and the tightest binding occurs with Nd(3+) and Ho(3+), suggesting that metal binding may not be the rate-limiting step of the DNAzyme catalysis.
TL;DR: The developed λ-exo cleavage-induced DNAzyme releasing strategy opens a promising avenue for monitoring activity and inhibition of nucleotide kinase, and should be also easily extended for the sensitive detection toward many other nucleic acid enzymes.
Abstract: The T4 polynucleotide kinase (T4 PNK) plays an essential role in the cellular responses to nucleic acid strand damage. Herein, a simple and sensitive fluorescence approach for monitoring T4 PNK activity was proposed based on a λ-exonuclease (λ-exo) cleavage-induced DNAzyme releasing strategy. A hairpin-shaped DNA probe that contains the sequence of 8-17 DNAzyme as a built-in suppressed catalytic unit was designed. After phosphorylation by T4 PNK followed with the immediate λ-exonuclease (λ-exo) cleavage, the 8-17 DNAzyme unit was successfully released and used for the cyclic cleavage toward the molecular beacon substrate, resulting in an evident fluorescence signal enhancement. With the currently developed λ-exo cleavage reaction and DNAzyme-based platform, the amplified detection of T4 PNK with a low detection limit of 0.005 U mL −1 could be achieved. Furthermore, the inhibition effects of adenosine diphosphate, ammonium sulfate, and sodium hydrogen phosphate have been evaluated. The developed λ-exo cleavage-induced DNAzyme releasing strategy opens a promising avenue for monitoring activity and inhibition of nucleotide kinase, and should be also easily extended for the sensitive detection toward many other nucleic acid enzymes and may find widespread applications in biological process researches, drug discovery, and clinic diagnostics.
TL;DR: The capability of the peroxidase-mimicking DNAzyme as a platform for fluorogenic assays was demonstrated through designing model geno- and aptasensor for the detection of a tumor marker DNA and a low molecular weight analyte, adenosine 5'triphosphate (ATP), respectively.
Abstract: This work demonstrates the use of the peroxidase-mimicking DNAzyme (peroxidase-DNAzyme) as general and inexpensive platform for development of fluorogenic assays that do not require organic fluorophores. The system is based on the affinity interaction between the peroxidase-DNAzyme bearing hairpin sequence and the analyte (DNA or low molecular weight molecule), which changes the folding of the hairpin structure and consequently the activity of peroxidase-DNAzyme. Hence, in the presence of the analyte the peroxidase-DNAzyme structure is disrupted and does not catalyze the aerobic oxidation of l-cysteine to cystine. Thus, l-cysteine is not removed from the system and the fluorescence of the assay increases due to the in situ formation of fluorescent CdS nanocrystals. The capability of the system as a platform for fluorogenic assays was demonstrated through designing model geno- and aptasensor for the detection of a tumor marker DNA and a low molecular weight analyte, adenosine 5′triphosphate (ATP), respecti...
TL;DR: The development of a simple DNA sensor based on DNAzyme and PCR and aimed at the detection of low concentrations of zinc (II) ions, which showed sensitivity (10 nM) and high specificity for zinc ion detection is described.
Abstract: The development of a simple sensor (9NL27-Zn) based on DNAzyme and PCR and aimed at the detection of low concentrations of zinc (II) ions is described. A specific Zn(II)-dependent DNAzyme (9NL27) with DNA-cleaving activity was employed. In the presence of zinc (II), the DNAzyme hydrolyzed DNA substrate into two pieces (5' and 3' fragments), forming 3'-terminal hydroxyl in the 5' fragment and 5'-phosphate in the 3' fragments. Subsequently, the 5' fragment left the DNAzyme and bound a short DNA template. The 5' fragment was used as a primer and extended a single-stranded full-length template by Taq polymerase. Finally, this full-length template was amplified by PCR. The amplified products had a quantitative relationship with Zn(II) concentration. Under our experimental conditions, the DNA sensor showed sensitivity (10 nM) and high specificity for zinc ion detection. After improvement of the DNA sensor, the detection limit can reach 1 nM. The simple DNA sensor may become a DNA model for the detection of trace amounts of other targets.
TL;DR: A novel GTP sensor coupled with λ exonuclease cleavage reaction and nicking enzyme assisted fluorescence signal amplification process is reported, which provides a platform for detecting GTP and shows great potential in analyzing a variety of targets by combining deoxyribozymes with signal amplification strategy.
Abstract: The self-phosphorylating deoxyribozymes identified by in vitro selection can catalyze their own phosphorylation by utilizing phosphate donor guanosine-5′-triphosphate (GTP) which plays a critical role in a majority of cellular processes. On the basis of the unique properties of self-phosphorylating deoxyribozymes, we report a novel GTP sensor coupled with λ exonuclease cleavage reaction and nicking enzyme assisted fluorescence signal amplification process. The deoxyribozymes with special catalytic and structural characteristics display good stability compared to protein and RNA enzymes. We combined these properties with enzymatic recycling cleavage strategy to build a sensor which produced enhanced fluorescence signal. Sensitive and selective detection of GTP was successfully realized with the well-designed deoxyribozyme-based sensing platform by taking advantage of the self-phosphorylating ability of the kinase deoxyribozyme, efficient digestion capacity of λ exonuclease, and enzymatic recycling amplific...