Matter, energy and information network of a graphene-peptide-based fluorescent sensing system for molecular logic computing, detection and imaging of cancer stem cell marker CD133 in cells and tumor tissues.

Tumorigenesis, metastasis, and the recurrence of cancer, which may result from the abnormal presence or activation of cancer stem cells (CSCs), are involved in disorders of exchanged matter (biomarkers), energy and information in living organisms. Rapid and sensitive detection and imaging of CSC biomarkers (such as CD133) are helpful for early diagnosis and therapeutic evaluation of tumors. Recently, a preliminary exploration of a few affinity molecules (like peptide-based probes) has just begun for chemical measurements and imaging of CSC biomarker CD133. However, a comprehensive analysis of the matter, energy and information in an artificial molecular system has not been demonstrated and applied to biosensing and disease diagnosis. In this study, a graphene-peptide-based fluorescent sensing system was constructed by utilizing a graphene oxide platform and a CD133-specific recognition peptide and comprehensively analysed with respect to matter (molecular events), energy (fluorescence) and information flow. The molecular event interaction networks in this system were further used to perform molecular logic computing, for the sensitive detection of CSC marker CD133 (with a linear range from 0 to 630 nM and a detection limit of 7.91 nM), and for an application involving targeting the imaging of cells and tumor tissues that highly express CD133 (with a detection limit of 1.1 × 103 cells per mL for CT26 CSCs). The present report will provide more opportunities for the development and design of molecular-level intelligent complex systems and will probably promote the development of artificial intelligent sensing and treatment systems, a molecular-level "Internet of Things", and artificial life.

The Boolean logic tree of molecular self-assembly system based on cobalt oxyhydroxide nanoflakes for three-state logic computation, sensing and imaging of pyrophosphate in living cells and in vivo.

Sensing of pyrophosphate (PPi) is helpful to better understand many life processes and diagnose various early-stage diseases. However, many traditional reported methods based on artificial receptors for sensing of PPi exhibit some disadvantages including difficulties in designing appropriate binding sites and complicated multi-step assembly/functionalization. Thus, it is significantly important and a big challenge to know how to use a simple molecular self-assembly or an interaction system to solve the above-mentioned limits to achieve the quantitative analysis of specific substances in the system. Based on the natural connection and similarity (such as stimulus responsiveness) between sensing and logic computing, in this study, the Boolean logic tree of molecular self-assembly system based on the cobalt oxyhydroxide (CoOOH) nanoplatform is constructed and applied to organize and connect "plug and play" molecular events (fluorescent dye, acridine orange and anion, PPi). By using molecules as inputs and the corresponding fluorescence signal as the output, the CoOOH-based molecular self-assembly system can be programmed for three-input fluorescent Boolean logic computation, fluorescent three-state logic computation, detection of PPi (linear range from 50 to 6400 nM with a detection limit of 20 nM) and even for imaging in living cancer cells and in vivo (in systems such as Zebrafish and Carassius auratus). Our approach adds a new dimension for expanding molecular logic computing and sensing systems, which will not only provide more opportunities for developing novel logic computing paradigms, but also be helpful in promoting the development and applications of intelligent molecular computing and sensing systems.

Directly repurposing waste optical discs with prefabricated nanogrooves as a platform for investigation of cell-substrate interactions and guiding neuronal growth.

Due to rapid change in information technology, many consumer electronics become electronic waste which is the fastest-growing pollution problems worldwide. In fact, many discarded electronics with prefabricated micro/nanostructures may provide a good basis to fulfill special needs of other fields, such as tissue engineering, biosensors, and energy. Herein, to take waste optical discs as an example, we demonstrate that discarded electronics can be directly repurposed as highly anisotropic platforms for in vitro investigation of cell behaviors, such as cell adhesion, cell alignment, and cell-cell interactions. The PC12 cells cultured on biocompatible DVD polycarbonate layers with flat and grooved morphology show a distinct cell morphology, indicating the topographical cue of nanogrooves plays a key role in guidance of neurites growth. By further monitoring cell morphology and alignment of PC12 cells cultured on the DVD nanogrooves at different differentiation times, we find that cell contact interaction with nanotopographies is dynamically adjustable with differentiation time from initial disorder to final order. This study adds a new dimension to not only solving the problems of supply of materials and fabrication of nanopatterns in neural tissue engineering, but may also offering a new promising way of waste minimization or reuse for environmental protection.

[Cloning and expression of the cry1Ac-tchiB fusion gene from Bacillus thuringinesis and Tobacco and its insecticidal synergistic effect].

A new fusion gene cry1Ac-tchiB was constructed to enhance the toxicity of crystal proteins, the cry1Ac gene of Bacillus thuringiensis strain 4.0718 was combined with a tchiB (deleted signal peptide and Enterokinase site sequence). In this process, the Enterokinase site sequence was inserted into the midst of these two genes. Then the combined fragment carrying the upstream promoter region and the downstream terminator region of cry1Ac gene were cloned into the shuttle vector pHT315. And after a series of enzyme digestions and subclonings two new expression vector pHUAccB6 and pHUAccB7 were obtained. The two vectors were transformed into B. thuringiensis acrystalliferous strain XBU001 with electroporation to obtain the recombinant strain HAccB6 and HAccB7. The fusion gene was expressed and the expression product was detected by SDS-PAGE. The result indicated that the recombinant Cry1Ac-tchiB protein accumulated to the level of 61.38% of total bacterial proteins. Cry1Ac protein accumulated to the level of 42% of total bacterial proteins. Chitinase activities is 5.2 time more than that of the control strain. Under Atomic Force Microscopy and SEM of crystals protein, there were some bipy ramidal crystals with a size of 1.5 x 3.0 microm. Bioassay showed that the fusion crystals from recombinant strain HAccB6 and HAccB7 were high toxic against third-instar larvae of Helicourpa armigora with the LC50 (after 72h) value of 9.10 micro/mL and 11.34 micro/mL.The constructed fusion proteins had more toxicity than Cry1Ac crystal proteins. The study will enhances the toxicity of B. thuringiensis Cry toxins protein and makes a ground for constructing the fusion genes of B. thuringiensis cry gene and other foreign toxin genes and the recombinant strain with high toxicity.