Synthetic molecular probes, chemosensors, and nanosensors used in combination with innovative assay protocols hold great potential for the development of robust, low-cost, and fast-responding sensors that are applicable in biofluids (urine, blood, and saliva). Particularly, the development of sensors for metabolites, neurotransmitters, drugs, and inorganic ions is highly desirable due to a lack of suitable biosensors. In addition, the monitoring and analysis of metabolic and signaling networks in cells and organisms by optical probes and chemosensors is becoming increasingly important in molecular biology and medicine. Thus, new perspectives for personalized diagnostics, theranostics, and biochemical/medical research will be unlocked when standing limitations of artificial binders and receptors are overcome. In this review, we survey synthetic sensing systems that have promising (future) application potential for the detection of small molecules, cations, and anions in aqueous media and biofluids. Special attention was given to sensing systems that provide a readily measurable optical signal through dynamic covalent chemistry, supramolecular host-guest interactions, or nanoparticles featuring plasmonic effects. This review shall also enable the reader to evaluate the current performance of molecular probes, chemosensors, and nanosensors in terms of sensitivity and selectivity with respect to practical requirement, and thereby inspiring new ideas for the development of further advanced systems.

The discovery of the medicinal properties of gold complexes has fuelled the design and synthesis of new anticancer metallodrugs, which have received special attention due to their unique modes of action. Current research in the development of gold compounds with therapeutic properties is predominantly focused on the molecular design of drug leads with superior pharmacological activities, e.g., by introducing targeting features. Moreover, intensive research aims at improving the physicochemical properties of gold compounds, such as chemical stability and solubility in the physiological environment. In this regard, the encapsulation of gold compounds in nanocarriers or their chemical grafting onto targeted delivery vectors could lead to new nanomedicines that eventually reach clinical applications. Herein, we provide an overview of the state‐of‐the‐art progress of gold anticancer compounds, andmore importantly we thoroughly revise the development of nanoparticle‐based delivery systems for gold chemotherapeutics.

The degradation of mesoporous silica particles (MSPs) in water is a key aspect that boosts their use especially in bio-related fields. Although MSP degradation in aqueous media has been proven, big efforts have been devoted to tuning silica dissolution in order to obtain functional materials whose degradation can be finely controlled and enhanced, to tackle the issue of bioaccumulation. In particular, the introduction of stimuli-responsive functional groups into the silica framework was proven to be a successful strategy. Yet, the fast dissolution of silica particles in aqueous media in the absence of external stimuli has to be fully addressed. In this context, we reported herein the preparation and thorough characterisation of MSPs containing imine groups embedded within the silica framework (Im-MSPs). Particles with different contents of imine groups have been investigated in order to assess the effect on the physicochemical properties and the Im-MSPs showed fast degradation in both acidic and neutral aqueous solutions, at a rate that depended on the pH value. Of special interest is their fast degradation at acidic pH, where instead MSPs are normally more stable. The described results unveil the potential of these particles in applications that require a fast degradation in aqueous media.

The rapid and cost‐effective detection of food contaminants such as toxins and pathogens is a major challenge and a key concern for food safety. To this end, innovative, fast, cost‐effective, and easy‐to‐use sensors must be developed at the point where food is produced, distributed, and consumed. Therefore, timely detection and response to food contaminants can improve human health and reduce economic burden. However, affordable sensor technologies with specificity, sensitivity, and speed are required, which can be used by non‐specialized personnel and enable high throughput analysis. In this respect, advances in the development of nanoparticle‐based sensors, i.e., nanosensors, have shown the potential to provide the much‐anticipated versatile sensors. In addition, multiplex detection, i.e., the ability to detect multiple targets simultaneously, is another strategy facilitated by nanoparticle‐based sensors and will enable further improvements in sensor performance that are important for developing effective monitoring. This review summarizes the nanosensors for multiplex sensing of food samples with respect to hazardous contaminates reported over the past few years. In addition, special attention is paid to providing the reader with promising design principles and the current performance of the sensitivity and selectivity of such sensors for practical requirements, thereby inspiring new ideas for developing further advanced systems.