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Cu-ion-modified graphene oxide nanoparticles, Cu-GO NPs, act as a heterogeneous catalyst mimicking functions of horseradish peroxidase, HRP, and of NADH peroxidase. The Cu-GO NPs catalyze the oxidation of dopamine to aminochrome by HO and catalyze the generation of chemiluminescence in the presence of luminol and HO. The Cu-GO NPs provide an active material for the chemiluminescence detection of HO and allow the probing of the activity of HO-generating oxidases and the detection of their substrates. This is exemplified with detecting glucose by the aerobic oxidation of glucose by glucose oxidase and the Cu-GO NP-stimulated chemiluminescence intensity generated by the HO product. Similarly, the Cu-GO NPs catalyze the HO oxidation of NADH to the biologically active NAD cofactor. This catalytic system allows its conjugation to biocatalytic transformations involving NAD-dependent enzyme, as exemplified for the alcohol dehydrogenase-catalyzed oxidation of benzyl alcohol to benzoic acid through the Cu-GO NPs-catalyzed regeneration of NAD.

The stratum corneum, the most superficial layer of the skin, protects the body against environmental hazards and presents a highly selective barrier for the passage of drugs and cosmetic products deeper into the skin and across the skin. Nanomaterials can effectively increase the permeation of active molecules across the stratum corneum and enable their penetration into deeper skin layers, often by interacting with the skin and creating the distinct sites with elevated local concentration, acting as reservoirs. The flux of the molecules from these reservoirs can be either limited to the underlying skin layers (for topical drug and cosmeceutical delivery) or extended across all the sublayers of the epidermis to the blood vessels of the dermis (for transdermal delivery). The type of the nanocarrier and the physicochemical nature of the active substance are among the factors that determine the final skin permeation pattern and the stability of the penetrant in the cutaneous environment. The most widely employed types of nanomaterials for dermal and transdermal applications include solid lipid nanoparticles, nanovesicular carriers, microemulsions, nanoemulsions, and polymeric nanoparticles. The recent advances in the area of nanomaterial-assisted dermal and transdermal delivery are highlighted in this review.

Desorption electrospray ionization mass spectrometry imaging (DESI‐MSI) is one of the least specimen destructive ambient ionization mass spectrometry tissue imaging methods. It enables rapid simultaneous mapping, measurement, and identification of hundreds of molecules from an unmodified tissue sample. Over the years, since its first introduction as an imaging technique in 2005, DESI‐MSI has been extensively developed as a tool for separating tissue regions of various histopathologic classes for diagnostic applications. Recently, DESI‐MSI has also emerged as a versatile technique that enables drug discovery and can guide the efficient development of drug delivery systems. For example, it has been increasingly employed for uncovering unique patterns of in vivo drug distribution, the discovery of potentially treatable biochemical pathways, revealing novel druggable targets, predicting therapeutic sensitivity of diseased tissues, and identifying early tissue response to pharmacological treatment. These and other recent advances in implementing DESI‐MSI as the tool for the development of novel therapies are highlighted in this review.

The preparation of magnetically separable silica microcapsules that incorporate in their inner shell a chiral catalyst and their application in asymmetric transfer hydrogenation reactions are described. The preparation method is based on the emulsification of an oil phase containing chloroform, a modified Noyori Ru‐TsDPEN catalyst, tetraethoxysilane (TEOS), and hydrophobic magnetic nanoparticles in water in the presence of an appropriate surfactant, followed by an interfacial polycondensation process under basic conditions to generate a silica shell around the oil droplets. The resulting catalytic microreactors can be considered a “quasi‐homogeneous” system because the immobilized chiral catalyst reacts in a homogeneous zone, the microcapsule core filled with an organic solvent. The catalytic activity was tested in the asymmetric transfer hydrogenation of ketones in an aqueous medium. The catalytic reactions took place only in the presence of surfactants. In addition, the judicious selection of the surfactant plays a crucial role in enhancing the reaction progress through the emulsion‐solid transfer (EST) approach. The catalytic activity of the Ru‐TsDPEN catalyst immobilized within the silica microcapsules was superior to the same catalyst supported on silica microspheres or linked to the backbone of a silica sol–gel matrix, which indicates the importance of the homogeneous zones for the reactions.