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To date, two-dimensional (2D) and three-dimensional (3D) metal organic frameworks (MOFs) have been promising materials for applications in electrocatalysis, separation, and sensing. However, the exploration of a simple method for simultaneous fabrication of 2D/3D MOFs on a surface remains challenging. Herein, a one-step and in situ electrosynthesis strategy for fabrication of 2D Hemin-bridged MOF sheets (Hemin-MOFs) or 2D/3D Zn(II)-MOF hybrid nanocomposites on an electrode is reported. It exhibits varied morphologies at different electrodeposition times and attains a 2D/3D complex morphology by adding 1,3,5-benzenetricarboxylic acid (H3BTC) as an organic ligand. The morphology and size of 2D Hemin-MOFs are important factors that influence their performance. Since Pt nanoparticles (PtNPs) are grown on 2D Hemin-MOF sheets, this composite can serve as the peroxidase mimics and PtNPs can act as an anchor to capture the antibody. Therefore, this hybrid nanosheet-modified electrode is used as an electrochemical sensing platform for ultrasensitive pig immunoglobulin G (IgG) and the surface-protective antigen (Spa) protein of Erysipelothrix rhusiopathiae immunodetection. Moreover, this work provides a new avenue for the electrochemical synthesis of 2D/3D MOF hybrid nanocomposites with a high surface area and biomimetic catalysts.

A porous graphene (PG) bionanocomposite of PG, gold nanoparticles (AuNPs) and anti-indole-3-acetic acid (anti-IAA) antibody for sensitive and label-free amperometric immunoassay of IAA was reported. A PG film was produced by a pre-reduction/electrochemical reduction process on a glassy carbon electrode (GCE) and then a homogeneous AuNPs layer electrodeposition on the PG film. The anti-IAA antibody was immobilized onto the AuNPs through electrostatic adsorption and covalent conjugation. Scanning electron microscopy (SEM), transmission electron microscopy (TEM), Raman spectroscopy, energy dispersive spectroscopy (EDS), Fourier transform infrared spectroscopy (FTIR), cyclic voltammetry (CV), elecro-chemical impedance spectroscopy (EIS), ultraviolet visible spectroscopy (UV-vis) and differential pulse voltammetry (DPV) were used to characterize the PG film and the stepwise modification of the immunosensor. The electrochemical immunosensor exhibited a wide linear range from 2 × 10-11 to 2 × 10-8 g mL-1 with a detection limit of 0.016 ng mL-1 (S/N = 3) and showed significant linearity R2 = 0.9970. In addition, the proposed immunosensor showed acceptable selectivity and has been applied to the determination of IAA in the extract samples of several plant seeds with acceptable relative derivation (%) ranging from -5.25% to 4.24% between the immunosensor and high performance liquid chromatography. The proposed chemical pre-reduction and electro-reduction guided protocol can be extended to the preparation of many other functionalized PG nanocomposite films for wide applications.

To carry out genetic diagnosis for a fetus.Chromosome G-banding and chromosomal microarray analysis (CMA) were carried out for a fetus with abnormal morphology of lateral cerebral fissure.The karyotype of the fetus was normal, but CMA showed that it has carried a 1.4 Mb deletion at 17p13.3 region, which suggested a diagnosis of Miller-Dieker syndrome (MDS).Familiarity with clinical features and proper selection of genetic testing method are crucial for the diagnosis of MDS. Attention should be paid to microdeletions and microduplications which can be missed by conventional chromosomal karyotyping.

A simple and rapid electrochemical synthesis strategy for in-situ fabrication of toluidine blue (TB)-functionalized metal organic framework (TB@MOFs) thin films via one-step reduction approach was reported. The TB@MOFs thin layer has been synthesized on the working electrode surface in different times at room temperature, and its morphology and thickness was characterized by varied instruments, including scanning electron microscope, transmission electron microscope, and scanning ion conductance microscope. The prepared TB@MOFs shows exceptional electrochemical activity and stability under mild conditions, and its electrochemical response is dependent on the amount of TB molecules which are encapsulated in the MOFs. Based on the TB@MOFs sensing platform, a sensitive label-free electrochemical immunosensor for the detection of Indole-3-acetic acid (IAA, a plant hormone) was developed with a wide linear range (2.5 pg mL−1 - 5 ng mL−1) and a low detection limit (1.4 pg mL−1). Moreover, this immune sensor shows good sensitivity and selectivity in real samples for IAA detection.

A porous thiolated polymer nanocomposite for sensitive and selective amperometric immunoassay of phytohormone (with indole-3-acetic acid (IAA) as the model) was reported, with a detection limit down to 0.13 pg/mL for IAA. Briefly, porous thiolated polymer nanocomposite was prepared via electro-assisted thiol-ene reaction of 2,5-dimercapto-1,3,4-thiadiazole (DMcT) with oxidized polypyrrole (PPy) which was electrosynthesized on a porous graphene (PG) modified glassy carbon electrode, yielding thiolated PPy (TPPy)-PG, then gold nanoparticles (AuNPs) was deposited on the TPPy-PG by electrochemical method to obtain AuNPs/TPPy-PG nanocomposite. Finally, the AuNPs-antibody (Ab)/AuNPs/TPPy-PG nanocomposite film was constructed via the specific chemical reaction between boronic acid functionalized AuNPs/TPPy-PG and the vicinal diol functionalized AuNPs labeled immunoglobulins G (AuNPs-IgG). Scanning electron microscopy (SEM), cyclic voltammetry (CV), ultraviolet visible spectroscopy (UV–vis) and differential pulse voltammetry (DPV) were used to characterize the nanocomposite film and the stepwise modification of the immunosensor. The prepared AuNPs-Ab/AuNPs/TPPy-PG nanocomposite material has uniform dispersion of the AuNPs on porous thiolated polymer nanocomposite as verified by SEM, and high activity of the immobilized Ab proved via DPV. The electrochemical immunosensor show good sensitivity, acceptable selectivity, reproducibility and stability.