The development of new food preservatives is essential to prevent foodborne outbreaks or food spoilage due to microbial growth, enzymatic activity or oxidation. Furthermore, new compounds that substitute the commonly used synthetic food preservatives are needed to stifle the rising problem of microbial resistance. In this scenario, we report herein, as far as we know, for the first time the use of the zein protein as a gating moiety and its application for the controlled release of essential oil components (EOCs). The design of microdevices consist of mesoporous silica particles loaded with essential oils components (thymol, carvacrol and cinnamaldehyde) and functionalized with the zein (prolamin) protein found in corn as a molecular gate. The zein protein grafted on the synthesized microdevices is degraded by the proteolytic action of bacterial enzymatic secretions with the consequent release of the loaded essential oil components efficiently inhibiting bacterial growth. The results allow us to conclude that the new microdevice presented here loaded with the essential oil component cinnamaldehyde improved the antimicrobial properties of the free compound by decreasing volatility and increasing local concentration.

A new delivery microdevice, based on hydrophobic oleic acid‐capped mesoporous silica particles and able to payload release in the presence of surfactants, has been developed. The oleic acid functionalization confers to the system a high hydrophobic character, which avoids cargo release unless surfactant molecules are present. The performance of this oleic‐acid capped microdevice in the presence of different surfactants is presented and its zero‐release operation in the absence of surfactants is demonstrated.

Antibody–drug conjugates (ADCs) represent a therapeutic modality that guides chemotherapies to tumoral cells by using antibodies against tumor-associated antigens (TAAs). The antibody and the chemotherapy or payload are attached by a chemical structure called the linker. The strategy for the development of this type of drug was based on several rational pillars, including the use of a very potent payload and the use of specific antibodies acting only on antigens expressed on tumoral cells. In this article, by using data from all approved ADCs that have received regulatory approval, we analyze the potential contribution of each ADC component to preclinical activity. We suggest that payload potency and the drug-to-antibody ratio (DAR) have a less relevant role in relation to efficacy than previously considered. Additionally, we have observed that some ADCs have been developed against antigens also present in non-transformed tissues, which could suggest that TAA specificity is not a mandatory requirement. Finally, we have identified that ADCs with payloads harboring more favorable physicochemical characteristics showed better potential activity. In this article, we also review other aspects that should be taken into consideration for ADC design, including linker structure, stability, conjugation type, pharmacokinetics, receptor internalization, and recycling. Based on currently available data, our study summaries different concepts that should be considered in the design of novel ADCs in the future.

In recent decades, the versatility of mesoporous silica particles and their relevance to develop controlled release systems have been demonstrated. Within them, gated materials able to modulate payload delivery represent great advantages. However, the role played by the porous matrix in this kind of systems is scarce. In this work, different mesoporous silica materials (MCM-41, MCM-48, SBA-15 and UVM-7) are functionalized with oleic acid as a molecular gate. All systems are fully characterized and their ability to confine the entrapped cargo and release it in the presence of bile salts is validated with release assays and in vitro digestion experiments. The cargo release profile of each synthesized support is studied, paying attention to the inorganic scaffold. Obtained release profiles fit to Korsmeyer–Peppas model, which explains the differences among the studied supports. Based on the results, UVM-7 material was the most appropriate system for duodenal delivery and was tested in an in vivo model of the Wistar rat. Payload confinement and its complete release after gastric emptying is achieved, establishing the possible use of mesoporous silica particles as protection and direct release agents into the duodenum and, hence, demonstrating that these systems could serve as an alternative to the administration methods employed until now.

Mesoporous silica microparticles functionalized with lactose for the specific release of essential oil components (EOCs) in the small intestine are presented. In vitro and in vivo intestinal models were applied to validate the microparticles (M41-EOC-L), in which the presence of lactase acts as the triggering stimulus for the controlled release of EOCs. Among the different microdevices prepared (containing thymol, eugenol and cinnamaldehyde), the one loaded with cinnamaldehyde showed the most significant Caco-2 cell viability reduction. On the other hand, interaction of the particles with enterocyte-like monolayers showed a reduction of EOCs permeability when protected into the designed microdevices. Then, a microdevice loaded with cinnamaldehyde was applied in the in vivo model of Wistar rat. The results showed a reduction in cinnamaldehyde plasma levels and an increase in its concentration in the lumen of the gastrointestinal tract (GIT). The absence of payload release in the stomach, the progressive release throughout the intestine and the prolonged stay of the payload in the GIT-lumen increased the bioavailability of the encapsulated compound at the site of the desired action. These innovative results, based on the specific intestinal controlled delivery, suggest that the M41-payload-L could be a potential hybrid microdevice for the protection and administration of bioactive molecules in the small intestine and colon.