Enzymes encapsulated in organic-inorganic hybrid nanoflower with spatial localization for sensitive and colorimetric detection of formate.

Formate is an important environmental pollutant, and meanwhile its concentration change is associated with a variety of diseases. Thus, rapid and sensitive detection of formate is critical for the biochemical analysis of complex samples and clinical diagnosis of multiple diseases. Herein, a colorimetric biosensor was constructed based on the cascade catalysis of formate oxidase (FOx) and horseradish peroxidase (HRP). These two enzymes were co-immobilized in Cu3(PO4)2-based hybrid nanoflower with spatial localization, in which FOx and HRP were located in the shell and core of nanoflower, respectively (FOx@HRP). In this system, FOx could catalyze the oxidation of formate to generate H2O2, which was then utilized by HRP to oxidize 2,2'-azino-bis-3-ethylbenzothiazoline-6-sulphonic acid to yield blue product. Ideal linear correlation could be obtained between the absorbance at 420 nm and formate concentration. Meanwhile, FOx@HRP exhibited excellent detection performance with low limit of detection (6 µM), wide linear detection range (10-900 µM), and favorable specificity, stability and reusability. Moreover, it could be applied in the detection of formate in environmental, food and biological samples with high accuracy. Collectively, FOx@HRP provides a useful strategy for the simple and sensitive detection of formate and is potentially to be used in biochemical analysis and clinical diagnosis.

Maltodextrin as wall material for microcapsules: A review.

Maltodextrin (MD) is a partially hydrolyzed product of starch that can be used to encapsulate food, medicine, essential oil and other substances. MD-based microcapsules can enhance the color, aroma, and taste of products, improve the solubility and stability of core materials, and slowly release the core materials for a long time to achieve certain specific uses. Therefore, the development of MD-based microcapsules is a key research field in food, pharmaceutics, cosmetics and other industries. In this paper, the progress of MD microcapsules and their applications in recent ten years is reviewed. First, the main characteristics of MD microcapsules are briefly introduced. Then, the preparation process, influencing factors, physical and chemical properties, stability, release mechanism and application in various fields of MD microcapsules are introduced in detail. This review is intended to provide reference on the properties of MD for researchers who desire to prepare microcapsules.

Stimulus responsive microcapsules and their aromatic applications.

Fragrances and essential oils are promising for a wide range of applications due to their pleasant odors and diverse effects. However, direct addition to consumer products has the disadvantages of short retention time and easy deterioration of odor. At the same time, releasing a large amount of odor in a short time may be an unpleasant experience, which severely limits the practical application of aromatic substances. Microencapsulation perfectly solves these problems. Stimuli-responsive microcapsules, which combine environmental stimulation with microencapsulation, can not only effectively prevent the rapid decomposition and evaporation of aroma components, but also realize the "on-off" intelligent release of aroma substances to environmental changes, which have great promise in the field of fragrances. In this review, the application of stimuli-responsive microcapsules in fragrances is highlighted. Firstly, various encapsulation materials used to prepare stimuli-responsive aromatic microcapsules are described, mainly including some natural polymers, synthetic polymers, and inorganic materials. Subsequently, there is a detailed description of the common release mechanisms of stimuli-responsive aromatic microcapsules are described in detail. Finally, the application and future research directions are given for stimuli-responsive aromatic microcapsules in new textiles, food, paper, and leather.

Adhesion advances: from nanomaterials to biomimetic adhesion and applications.

The field of adhesion has revealed a significant impact on numerous applications such as wound healing, drug delivery, electrically conductive adhesive, dental adhesive, and wood industry. Nanotechnology has continued to be the primary means to achieve adhesion. Among them, biological systems based on the unique structure of the nano-levels have developed excellent adhesion capabilities after billions of years of evolution and natural selection. Therefore, the research on bionic adhesion inspired by biological systems has gradually emerged. This review firstly focuses on the mechanism of adhesion, and secondly reports the effects of different nanomaterials on adhesion properties. Then based on the structure of mussels, geckos, tree frogs, octopuses, and other organisms, the research progress of biomimetic nanotechnology to achieve adhesion is summarized. Finally, the applications, challenges, and future directions of nanotechnology in new adhesive materials are provided.