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9. Channel Responses for the Molecule Release from Spherical Homogeneous Matrix Carriers

Author

Schäfer, Maximilian, Salinas, Yolanda, Ruderer, Alexander, Enzenhofer, Franz, Brüggemann, Oliver, Martínez-Máñez, Ramón, Rabenstein, Rudolf, Schober, Robert, and Haselmayr, Werner

Subjects
Computer Science - Emerging Technologies
Abstract

Molecular communications is a promising framework for the design of controlled-release drug delivery systems. Under this framework, drug carriers, diseased cells, and the channel are modeled as transmitters, absorbing receivers, and diffusive channel, respectively. In this paper, we investigate diffusion-based spherical matrix-type drug carriers, which are employed in medical applications. In a matrix carrier, the drug molecules are dispersed in the matrix core and diffuse from the inner to the outer layers of the carrier once immersed in a dissolution medium. We derive the channel response of the matrix carrier transmitter for an absorbing receiver and compare our results with commonly used point and transparent spherical transmitters to highlight the necessity of considering practical models. Furthermore, we derive a criterion for evaluating whether the release process or the channel dynamics are more important for the characteristics of the channel response of a drug delivery system. For the limiting regimes, where only the release process or the channel determine the behavior of the end-to-end system, we propose closed-form approximations for the channel response. Finally, we investigate the channel responses for the release of common therapeutic drugs, e.g., doxorubicin, from a diblock copolymer micelle acting as drug carrier., Comment: 30 pages, 8 figures, 2 tables, Submitted for possible journal publication in IEEE Transactions on Molecular, Biological and Multi-Scale Communications. arXiv admin note: text overlap with arXiv:2104.05332

Published
2021

23. Synthesis of a Pd 2 L 4 Hydrazone Molecular Cage Through Multiple Reaction Pathways.

Author

Montà-González, Giovanni, Martínez-Máñez, Ramón, and Martí-Centelles, Vicente

Subjects
*SUPRAMOLECULAR chemistry, *CHEMICAL bonds, *BONDS (Finance), *COMPARATIVE studies, *MOLECULES
Abstract

Molecular cages are preorganized molecules with a central cavity, typically formed through the reaction of their building blocks through chemical bonds. This requires, in most cases, forming and breaking reversible bonds during the cage formation reaction pathway for error correction to drive the reaction to the cage product. In this work, we focus on both Pd–ligand and hydrazone bonds implemented in the structure of a Pd2L4 hydrazone molecular cage. As the cage contains two different types of reversible bonds, we envisaged a cage formation comparative study by performing the synthesis of the cage through three different reaction pathways involving the formation of Pd–ligand bonds, hydrazone bonds, or a combination of both. The three reaction pathways produce the cage with yields ranging from 73% to 79%. Despite the complexity of the reaction, the cage is formed in a high yield, even for the reaction pathway that involves the formation of 16 bonds. This research paves the way for more sophisticated cage designs through complex reaction pathways. [ABSTRACT FROM AUTHOR]

Published
2024
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24. Antimicrobial Surfaces: Stainless Steel Functionalized with the Essential Oil Component Vanillin.

Author

Medaglia, Serena, Morellá-Aucejo, Ángela, Ruiz-Rico, María, Sancenón, Félix, Villaescusa, Luis A., Martínez-Máñez, Ramón, Marcos, M. Dolores, and Bernardos, Andrea

Subjects
STAINLESS steel, BACTERIAL adhesion, NOSOCOMIAL infections, STAPHYLOCOCCUS epidermidis, ESSENTIAL oils
Abstract

Pathogenic microorganisms can adhere to solid surfaces, leading to the formation of biofilms, thus building a physical barrier hindering the penetration and diffusion of antimicrobial compounds. In this context, the use of natural antimicrobial compounds, such as essential oil components, as substitutes for common synthetic antimicrobials in the fight to prevent antimicrobial resistance is explored. As stainless steel is one of the most widely used surfaces in different industries, we have developed an innovative antimicrobial treatment for stainless steel surfaces based on a multi-step functionalization process, in which the stainless steel surface is coated with a silica layer to which a vanillin derivative is covalently attached. The surface was analyzed by microscopy studies, indicating the correct immobilization on the surfaces. Antimicrobial studies (viability and bacterial adhesion assays) were performed against the bacteria Staphylococcus epidermidis, which is one of the most frequent causes of nosocomial infections. The results of the microbiological studies showed that vanillin-functionalized stainless steel surfaces reduce the bacteria viability by 100% and the biofilm formation on the stainless steel surface by 75% compared with non-functionalized surfaces, highlighting the contact-killing and adhesion resistance properties of the developed surface. Additional cycles using the functionalized surfaces showed good maintenance of the antimicrobial coating efficacy. Moreover, the surfaces coated with an intermediate silica layer demonstrated much greater antimicrobial activity than surfaces in which the active molecule was directly functionalized on the stainless steel surface. [ABSTRACT FROM AUTHOR]

Published
2024
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38. β‐Galactosidase‐Triggered Photodynamic Elimination of Senescent Cells with a Boron Dipyrromethene‐Based Photosensitizer.

Author

Chu, Jacky C. H., Escriche‐Navarro, Blanca, Xiong, Junlong, García‐Fernández, Alba, Martínez‐Máñez, Ramón, and Ng, Dennis K. P.

Subjects
PHOTOSENSITIZERS, BORON, REACTIVE oxygen species, PHOTODYNAMIC therapy, CELLULAR aging, STAINS & staining (Microscopy)
Abstract

Senescence is a cellular response having physiological and reparative functions to preserve tissue homeostasis and suppress tumor growth. However, the accumulation of senescent cells would cause deleterious effects that lead to age‐related dysfunctions and cancer progression. Hence, selective detection and elimination of senescent cells are crucial yet remain a challenge. A β‐galactosidase (β‐gal)‐activated boron dipyrromethene (BODIPY)‐based photosensitizer (compound 1) is reported here that can selectively detect and eradicate senescent cells. It contains a galactose moiety connected to a pyridinium BODIPY via a self‐immolative nitrophenylene linker, of which the photoactivity is effectively quenched. Upon interactions with the senescence‐associated β‐gal, it undergoes enzymatic hydrolysis followed by self‐immolation, leading to the release of an activated BODIPY moiety by which the fluorescence emission and singlet oxygen generation are restored. The ability of 1 to detect and eliminate senescent cells is demonstrated in vitro and in vivo, using SK‐Mel‐103 tumor‐bearing mice treated with senescence‐inducing therapy. The results demonstrate that 1 can be selectively activated in senescent cells to trigger a robust senolytic effect upon irradiation. This study breaks new ground in the design and application of new senolytic agents based on photodynamic therapy. [ABSTRACT FROM AUTHOR]

Published
2024
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48. Enzyme-Powered Gated Mesoporous Silica Nanomotors for On-Command Intracellular Payload Delivery

Author

Llopis-Lorente, Antoni, García-Fernández, Alba, Murillo-Cremaes, Nerea, Hortelão, Ana C., Patiño, Tania, Villalonga Santana, Reynaldo, Sancenón, Félix, Martínez-Máñez, Ramón, Sánchez, Samuel, Llopis-Lorente, Antoni, García-Fernández, Alba, Murillo-Cremaes, Nerea, Hortelão, Ana C., Patiño, Tania, Villalonga Santana, Reynaldo, Sancenón, Félix, Martínez-Máñez, Ramón, and Sánchez, Samuel

Abstract

The introduction of stimuli-responsive cargo release capabilities on self-propelled micro- and nanomotors holds enormous potential in a number of applications in the biomedical field. Herein, we report the preparation of mesoporous silica nanoparticles gated with pH-responsive supramolecular nanovalves and equipped with urease enzymes which act as chemical engines to power the nanomotors. The nanoparticles are loaded with different cargo molecules ([Ru(bpy)3]Cl2 (bpy = 2,2′-bipyridine) or doxorubicin), grafted with benzimidazole groups on the outer surface, and capped by the formation of inclusion complexes between benzimidazole and cyclodextrin-modified urease. The nanomotor exhibits enhanced Brownian motion in the presence of urea. Moreover, no cargo is released at neutral pH, even in the presence of the biofuel urea, due to the blockage of the pores by the bulky benzimidazole:cyclodextrin-urease caps. Cargo delivery is only triggered on-command at acidic pH due to the protonation of benzimidazole groups, the dethreading of the supramolecular nanovalves, and the subsequent uncapping of the nanoparticles. Studies with HeLa cells indicate that the presence of biofuel urea enhances nanoparticle internalization and both [Ru(bpy)3]Cl2 or doxorubicin intracellular release due to the acidity of lysosomal compartments. Gated enzyme-powered nanomotors shown here display some of the requirements for ideal drug delivery carriers such as the capacity to self-propel and the ability to “sense” the environment and deliver the payload on demand in response to predefined stimuli., “La Caixa” Banking Foundation, MINECO, BBVA Foundation, Generalitat Valenciana, Generalitat de Catalunya, European Union’s Horizon 2020 research and innovation program, Depto. de Química Analítica, Fac. de Ciencias Químicas, TRUE, pub

Published
2024

49. An enzyme-controlled mesoporous nanomachine for triple-responsive delivery

Author

Mayol Hornero, Beatriz, Dato, Victor, Rodriguez, Manuel, Lucena, Elena, Villalonga, Anabel, Díez, Paula, Jiménez Falcao, Sandra, Sancenón, Félix, Sánchez, Alfredo, Vilela García, Diana, Martínez Ruiz, María Paloma, Martínez-Máñez, Ramón, Villalonga Santana, Reynaldo, Mayol Hornero, Beatriz, Dato, Victor, Rodriguez, Manuel, Lucena, Elena, Villalonga, Anabel, Díez, Paula, Jiménez Falcao, Sandra, Sancenón, Félix, Sánchez, Alfredo, Vilela García, Diana, Martínez Ruiz, María Paloma, Martínez-Máñez, Ramón, and Villalonga Santana, Reynaldo

Abstract

Financial support from the Spanish Ministry of Economy and Competitiveness (projects CTQ2017-87954-P, PID2021-125723NBI00, MAT2015-64139-C4-1 and RTI2018-100910-B-C41) is gratefully acknowledged. The authors also thank the Generalitat Valencia (Project PROMETEO/2018/024) for support., The construction of a novel enzyme-controlled nanomachine with multiple release mechanisms for oncommand delivery is described. This nanodevice was assembled by modifying mesoporous silica nanoparticles with 2-(benzo[d]thiazol-2-yl)phenyl 4-aminobenzoate moieties, and further capped with b-cyclodextrin-modified glucose oxidase neoglycoenzyme. The device released the encapsulated payload in the presence of H2O2 and acidic media. The use of glucose as an input chemical signal also triggered cargo release through the enzymatic production of gluconic acid and hydrogen peroxide, and the subsequent disruption of the gating mechanism at the mesoporous surface. The nanodevice was successfully employed for the enzyme-controlled release of doxorubicin in HeLa cancer cells., Spanish Ministry of Economy and Competitiveness, Generalitat Valenciana, Depto. de Química Analítica, Fac. de Ciencias Químicas, TRUE, pub

Published
2024

50. A glutathione disulfide-sensitive Janus nanomachine controlled by an enzymatic and logic gate for smart delivery

Author

Mayol Hornero, Beatriz, Díez-Sánchez, Paula, Sánchez Sánchez, Alfredo, Torre, Cristina de la, Villalonga, Anabel, Lucena-Sánchez, Elena, Sancenón, Félix, Martínez Ruiz, María Paloma, Vilela García, Diana, Martínez-Máñez, Ramón, Villalonga Santana, Reynaldo, Mayol Hornero, Beatriz, Díez-Sánchez, Paula, Sánchez Sánchez, Alfredo, Torre, Cristina de la, Villalonga, Anabel, Lucena-Sánchez, Elena, Sancenón, Félix, Martínez Ruiz, María Paloma, Vilela García, Diana, Martínez-Máñez, Ramón, and Villalonga Santana, Reynaldo

Abstract

This work describes the assembly of a novel enzyme-controlled nanomachine operated through an AND Boolean logic gate for on-command delivery. The nanodevice was constructed on Au-mesoporous silica Janus nanoparticles capped with a thiol-sensitive gate-like molecular ensemble on the mesoporous face and functionalized with glutathione reductase on the gold face. This autonomous nanomachine employed NADPH and glutathione disulfide as input chemical signals, leading to the enzymatic production of reduced glutathione that causes the disruption of the gating mechanism on the mesoporous face and the consequent payload release as an output signal. The nanodevice was successfully used for the autonomous release of doxorubicin in HeLa cancer cells and RAW 264.7 macrophage cells., Spanish Ministry of Economy and Competitiveness, Generalitat Valenciana, Depto. de Química Analítica, Fac. de Ciencias Químicas, TRUE, pub

Published
2024

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