Logic-Gates of Gas Pressure for Portable, Intelligent and Multiple Analysis of Metal Ions

CRISPR/Cas12a-Powered Electrochemical Platform for Dual-miRNA Detection via an AND Logic Circuit

The CRISPR/Cas technology shows great potential in molecular detection and diagnostics. However, it is still challenging to detect multiple targets simultaneously using the CRISPR-Cas system. Herein, we ingeniously leverage the synergistic effect of two short single-stranded DNA activators to construct a CRISPR/Cas12a-driven electrochemical sensing platform based on an AND logic circuit ("AND" LC-CRISPR) for the simultaneous detection of dual miRNAs. Specifically, the exponential amplification reaction products triggered by the dual-specific miRNAs are designed as binary inputs to bind with Cas12a/crRNA, forming an AND logic circuit and activating the trans-cleavage ability of the CRISPR-Cas12a system. Subsequently, the hairpin probe biogate on the surface of the functionalized electrochemical signal probe (MB@HP-Fe-MOF) is cleaved by activated Cas12a, leading to the release of the encapsulated electroactive signal molecule methylene blue, thereby generating a strong electrochemical signal. As a result, this "AND" LC-CRISPR sensing platform, requiring only a single crRNA assembled with Cas12a, achieves simultaneous detection of miRNA-155 and miRNA-21 at concentrations as low as 3.2 fM. Moreover, the platform allows easy adjustment of the AND logic circuit inputs according to different detection targets, allowing it to be easily expanded for the analysis and diagnosis of other multibiomarkers. This approach demonstrates promising potential for future applications in intelligent diagnostic medicine.

Ultrasensitive Photoelectrochemical Biosensor for Dual-miRNAs Detection Based on Molecular Logic Gates and Methylene Blue Sensitized ZnO@CdS@Au Nanorods

The occurrence of cancer is often closely related to multiple tumor markers, so it is important to develop multitarget detection methods. By the proper design of the input signals and logical operations of DNA logic gates, detection and diagnosis of cancer at different stages can be achieved. For example, in the early stages, specific input signals can be designed to correspond to early specific tumor markers, thereby achieving early cancer detection. In the late stage, logic gates for multitarget detection can be designed to simultaneously detect multiple biomarkers to improve diagnostic accuracy and comprehensiveness. In this work, we constructed a dual-target-triggered DNA logic gate for anchoring DNA tetrahedra, where methylene blue was embedded in the DNA tetrahedra to sensitize ZnO@CdS@Au, achieving ultrasensitive detection of the target substance. We tested the response of AND and OR logic gates to the platform. For AND logic gates, the sensing platform only responds when both miRNAs are present. In the concentration range of 10 aM to 10 nM, the photoelectric signal gradually increases with an increase of the target concentration. Subsequently, we used OR logic gates for miRNA detection. Even if only one target exists, the sensing platform exhibits excellent performance. Similarly, within the concentration range of 10 aM to 10 nM, the photoelectric signal gradually increases with an increase of the target concentration. The minimum detection limit is 1.10 aM. Whether it is the need to detect multiple targets simultaneously or only one of them, we can achieve it by selecting the appropriate logic gate. This strategy holds promising application prospects in fields such as biosensing, medical diagnosis, and environmental monitoring.

CRISPR/Cas12a-derived ratiometric fluorescence sensor for high-sensitive Pb2+ detection based on CDs@ZIF-8 and DNAzyme

Benefiting from specific target recognition and trans-cleavage capabilities, the CRISPR/Cas12a system has great application prospects in the design of highly sensitive and rapid fluorescence biosensors. The CRISPR/Cas12a-based fluorophore-quencher molecular beacons exhibit single-color emission and are easily exposed to interference from environmental factors. Herein, we design a CRISPR/Cas12a-derived ratiometric fluorescence sensor for Pb2+ detection based on embedded carbon dots@zeolitic imidazolate framework-8 (CDs@ZIF-8) composites and DNAzyme. The functions of ZIF-8 about encapsulating red emissive CDs in the inner cavity and adsorbing DNA on the outer surface are integrated to establish dual fluorescence signals, thereby reducing the possibility of interference and improving sensing accuracy. The presence of Pb2+ is converted into the change of activator by the GR5 DNAzyme to activate the CRISPR/Cas12a system, which provides signal amplification through multiple turnovers of side branch cutting, achieving highly sensitive detection of Pb2+ with a low detection limit of 18 pM. This method has the advantages of simplicity, universality, and excellent quantitative ability, and has broad prospects in sensing applications.

Intelligent monitoring of the available lead (Pb) and cadmium (Cd) in soil samples based on half adder and half subtractor molecular logic gates

The available heavy metals in soil samples can cause the direct toxicity on ecosystems, plants, and human health. Traditional chemical extraction and recombinant bacterial methods for the available heavy metals assay often suffer from inaccuracy and poor specificity. In this work, we construct half adder and half subtractor molecular logic gates with molecular-level biocomputation capabilities for the intelligent sensing of the available lead (Pb) and cadmium (Cd). The available Pb and Cd can cleave DNAzyme sequences to release the trigger DNA, which can activate the hairpin probe assembly in the logic system. This multifunctional logic system can not only achieve the intelligent recognition of the available Pb and Cd according to the truth tables, but also can realize the simultaneous quantification with high sensitivity, with the detection limits of 2.8 pM and 25.6 pM, respectively. The logic biosensor is robust and has been applied to determination of the available Pb and Cd in soil samples with good accuracy and reliability. The relative error (Re) between the logic biosensor and the DTPA + ICP-MS method was from -8.1 % to 7.9 %. With the advantages of programmability, scalability, and multicomputing capacity, the molecular logic system can provide a simple, rapid, and smart method for intelligent monitoring of the available Pb and Cd in environmental samples.

Nano-Structural Superwetting Surfaces for Highly Reliable On-Site Detection of Bisphenol A

In the domain of big data geographic screening for environmental pollutants, the expeditious dissemination of testing results to environmental investigation professionals is pivotal in facilitating comprehensive analysis and the implementation of more efficacious strategies for managing environmental issues. However, this endeavor can prove to be particularly arduous when conducting examinations in remote, resource-scarce rural areas and field environments, where deficient infrastructure often emerges as the principal impediment to unimpeded environmental monitoring. Therefore, the development of a reliable and portable monitoring strategy with the ability to analyze large amounts of data is highly required. Here, a deep-learning (DL)-assisted portable sensing strategy was developed based on thermal and pH dual-responsive nano-structural superwetting surfaces, for highly reliable, quick, and field monitoring of environmental pollutants. In our experiment, bisphenol A (BPA) was selected as the representative pollute. The achieved limit of detection, attaining a remarkably low value of 1.05 μM, unequivocally adhered to stringent international testing standards for evaluating the migration of BPA in thermal paper. Based on a DL image classification algorithm, highly precise predictions regarding the migration of BPA concentration were achieved, with an accuracy rate exceeding 99%. Furthermore, it successfully facilitated automated and exceedingly reliable monitoring of the migration of BPA from thermal paper within the principal provinces of thermal paper production in China. This strategy engenders the potential to establish correlations between environmental pollutant concentrations in specific regions and the prevalence of certain human ailments.

Multifunctional dumbbell probes-based logic circuits: microRNAs logic detection and tumor cells identification

BACKGROUND

The powerful logic processing capability of DNA logic circuits over multiple input signals perfectly meets the demands of multi-biomarker-based clinical diagnostics. As important biomarkers for cancer diagnosis and treatment, the orthogonal differential expression of microRNAs (miRNAs) in different diseases and different cancer cells makes the precise logical detection of multiple miRNAs particularly critical.

RESULTS

Therefore, we constructed two fundamental "AND" and "OR" logic gates and one "AND-OR" logic gate on the basis of our proposed multifunctional dumbbell probes. These logic gates allowed for the logical profiling of multiple cancer-associated miRNAs. In addition, by making simple adjustments to the functional modules of multifunctional dumbbell probes, the three logic gates we proposed could be easily transformed without the use of sophisticated probe design. Remarkably, these logic gates, in particular the "AND-OR" logic gate, were able to compute several miRNAs simultaneously, demonstrating excellent cell identification capabilities.

SIGNIFICANCE

Overall, this work provided a new idea for accurately distinguishing multiple cell types and showed great application prospects.

Leveraging DNA-Based Nanostructures for Advanced Error Detection and Correction in Data Communication

This study demonstrates the implementation of the Hamming code using DNA-based nanostructures for error detection and correction in communication systems. The designed DNA nanostructures conduct logical operations to compute check codes and identify and correct erroneous data based on fluorescence signals. The execution of intricate DNA logic operations requires individuals with specialized training. By interpretation of the fluorescence signals generated by the DNA nanostructures, binary language can be extracted, effectively protecting data security. The findings highlight the potential of DNA as a versatile platform for reliable data transmission.