An enhanced chemiluminescence bioplatform by confining glucose oxidase in hollow calcium carbonate particles

Facile Synthesis of MXene-Ti3C2/Co Nanosheet Hydrogel Sensor with the Assistance of a Smartphone for On-Site Monitoring of Glucose in Beverages

A one-step cobaltous chloride (CoCl₂) molten salt method was employed to prepare multilayer MXene-Ti₃C₂/Co materials with further ultrasonic treatment to acquire single-layer MXene-Ti₃C_2/Co nanosheets (NSs). MXene-Ti₃C₂/Co NSs were characterized, and their enzyme-like activities were investigated. Under the catalysis of MXene-Ti₃C₂/Co NSs, 3,3',5,5'-tetramethylbenzidine (TMB) could be oxidized by H₂O₂, with the color changing from colorless to blue. The affinity of MXene-Ti₃C₂/Co NSs to H₂O₂ and TMB was better than that of nanozymes reported in previous studies. The MXene-Ti₃C₂/Co NSs were used for the colorimetric determination of H₂O₂/glucose, with limits of detection (LODs) of 0.033 mM and 1.7 μM, respectively. MXene-Ti₃C₂/Co NSs embedded in sodium alginate (SA) hydrogel were used to construct a sensor platform. The digital pictures combined with a smartphone-installed app (color recognizer) could be used to analyze RGB values for colorimetric detection of glucose in beverages. This point-of-care testing platform has the advantages of cost-effectiveness and good transferability, with the potential to realize quick, intelligent and on-site detection.

One-Step Fabrication of Coconut-Like Capsules via Competitive Reactions at an All-Aqueous Interface for Enzyme Immobilization

A concept of interfacial competitive reaction between biomineralization and alginate gelation at an all-aqueous single-emulsion droplet interface to prepare robust coconut-like capsules (inner hard wall and outer soft wall) is developed. The concept is further applied for enzyme immobilization with high encapsulation efficiency, enzyme loading, mass transfer coefficient, and recyclability. The thickness and swelling properties of the shell are simply tunable by a competitive reaction. Our platform may open a green, facile, and efficient way to prepare organic-inorganic hybrid sustainable materials with tailored compositions and structures.

Improvement Strategies, Cost Effective Production, and Potential Applications of Fungal Glucose Oxidase (GOD): Current Updates

Fungal glucose oxidase (GOD) is widely employed in the different sectors of food industries for use in baking products, dry egg powder, beverages, and gluconic acid production. GOD also has several other novel applications in chemical, pharmaceutical, textile, and other biotechnological industries. The electrochemical suitability of GOD catalyzed reactions has enabled its successful use in bioelectronic devices, particularly biofuel cells, and biosensors. Other crucial aspects of GOD such as improved feeding efficiency in response to GOD supplemental diet, roles in antimicrobial activities, and enhancing pathogen defense response, thereby providing induced resistance in plants have also been reported. Moreover, the medical science, another emerging branch where GOD was recently reported to induce several apoptosis characteristics as well as cellular senescence by downregulating Klotho gene expression. These widespread applications of GOD have led to increased demand for more extensive research to improve its production, characterization, and enhanced stability to enable long term usages. Currently, GOD is mainly produced and purified from Aspergillus niger and Penicillium species, but the yield is relatively low and the purification process is troublesome. It is practical to build an excellent GOD-producing strain. Therefore, the present review describes innovative methods of enhancing fungal GOD production by using genetic and non-genetic approaches in-depth along with purification techniques. The review also highlights current research progress in the cost effective production of GOD, including key advances, potential applications and limitations. Therefore, there is an extensive need to commercialize these processes by developing and optimizing novel strategies for cost effective GOD production.

Cytoglobin: a potential marker for adipogenic differentiation in preadipocytes in vitro

Obesity, mainly characterized by the excess fat storage, is a global health problem resulting in serious morbidity and mortality. Identification of molecular mechanisms in adipogenic differentiation pathway might lead to development of new strategies for diagnosis, prevention and therapy of obesity and associated diseases. Discovery of new genes and proteins in the differentiation pathway could help to understand the key specific regulators of the adipogenesis. Cytoglobin (Cygb), identified as a new globin family member protein, is expressed in various tissues. Although its interaction with oxygen and nitric oxide indicates the potential role in antioxidant pathways, the exact role remains unclear. In the current study, expression level of Cygb was determined in proliferating and differentiating 3T3-F442A cells by gene expression and protein expression analysis. Results revealed that Cygb expression up-regulated in differentiated cells in parallel with adipogenic differentiation markers; PPARγ, CEBPα and FABP4 expressions. Besides, Cygb overexpression in preadipocytes contributed to the adipogenic differentiation as verified by detection of higher lipid droplets and increased PPARγ, CEBPα and FABP4 expressions with respect to control cells. These findings will shed light on the unknown roles of Cygb in adipogenesis and obesity.

Bis-three-way junction nanostructure and DNA machineries for ultrasensitive and specific detection of BCR/ABL fusion gene by chemiluminescence imaging

A novel G-quadruplex DNAzyme-driven chemiluminescence (CL) imaging method has been developed for ultrasensitive and specific detection of BCR/ABL fusion gene based on bis-three-way junction (bis-3WJ) nanostructure and cascade DNA machineries. Bis-3WJ probes are designed logically to recognize BCR/ABL fusion gene, which forms the stable bis-3WJ nanostructure for the activation of polymerase/nicking enzyme machineries in cascade, resulting in synthesis of DNAzyme subunits. These DNAzyme subunits can form integrated DNAzyme by self-assembly to catalyze CL substrate, thus providing an amplified signal for the sensing events or outputs for AND logic operation. The imaging method achieved ultrasensitive detection of BCR/ABL fusion gene with a low detection limit down to 23 fM. And this method exhibited wide linear ranges over seven orders of magnitude and excellent discrimination ability toward target. In addition, an acceptable recovery was obtained in complex matrix. It is notable that this biosensing strategy possesses merits of homogenous, isothermal and label-free assay system. Therefore, these merits endow the developed imaging method with a potential tool for CML diagnosis.