Fabrication of rapid-biodegradable nano-vectors for endosomal-triggered drug delivery

A Rapid pH-Responsive Pyraclostrobin Delivery System with Enhanced Membrane Passing Property and Fungicidal Activity against Botrytis cinerea

As the second most important fungal pathogen, Botrytis cinerea (B. cinerea) poses a serious threat to crop yields and agricultural safety. Pyraclostrobin (PYR), a broad-spectrum QoI fungicide, has been widely utilized since its launch in 2003. However, the inhibitory effects of both PYR technical and PYR formulations on B. cinerea are not outstanding. Even at a concentration of 50 μg/mL, the inhibition rates of B. cinerea by both PYR technical and PYR formulations remain below 85%. In this work, we prepared an acid-responsive Pickering emulsion encapsulating PYR (PYR@BTIB-PE), which completely inhibited B. cinerea at low concentrations (25 μg/mL) for the first time. The PYR@BTIB-PE achieved fragmentation and release within 4 min at pH 5, which was consistent with the pH around B. cinerea. The PYR@BTIB-PE can rapidly release PYR when B. cinerea infected and increased the concentration of PYR around the B. cinerea, thereby enhancing the efficacy of PYR. In addition, the released organic solvent from PYR@BTIB-PE enhanced the passing property of the B. cinerea membrane, facilitating more PYR to enter the body of B. cinerea. The improvement of the membrane passing property and rapid response release of PYR@BTIB-PE worked together to achieve complete inhibition of B. cinerea. Furthermore, the flexible and amphiphilic structures of PYR@BTIB-PE increased its interaction with the leaf surface, completely suppressed droplet splashing, and promoted droplet spreading, thereby reducing pesticide loss and improving the utilization rate of the pesticide. This study presents an efficient and rapid strategy for inhibiting B. cinerea and is also expected to be extended to other antifungal preparations.

Tumor microenvironment-responsive degradable silica nanoparticles: design principles and precision theranostic applications

Silica nanoparticles have emerged as promising candidates in the field of nanomedicine due to their remarkable versatility and customizable properties. However, concerns about their potential toxicity in healthy tissues and organs have hindered their widespread clinical translation. To address this challenge, significant attention has been directed toward a specific subset of silica nanoparticles, namely degradable silica nanoparticles, primarily because of their excellent biocompatibility and responsive biodegradability. In this review, we provide a comprehensive understanding of degradable silica nanoparticles, categorizing them into two distinct groups: inorganic species-doped and organic moiety-doped silica nanoparticles based on their framework components. Next, the recent progress of tumor microenvironment (TME)-responsive degradable silica nanoparticles for precision theranostic applications is summarized in detail. Finally, current bottlenecks and future opportunities of theranostic nanomedicines based on degradable silica nanoparticles in clinical applications are also outlined and discussed. The aim of this comprehensive review is to shed light on the potential of degradable silica nanoparticles in addressing current challenges in nanomedicine, offering insights into their design, applications in tumor diagnosis and treatment, and paving the way for future advancements in clinical theranostic nanomedicines.

Drug Delivery by Ultrasound-Responsive Nanocarriers for Cancer Treatment

Conventional cancer chemotherapies often exhibit insufficient therapeutic outcomes and dose-limiting toxicity. Therefore, there is a need for novel therapeutics and formulations with higher efficacy, improved safety, and more favorable toxicological profiles. This has promoted the development of nanomedicines, including systems for drug delivery, but also for imaging and diagnostics. Nanoparticles loaded with drugs can be designed to overcome several biological barriers to improving efficiency and reducing toxicity. In addition, stimuli-responsive nanocarriers are able to release their payload on demand at the tumor tissue site, preventing premature drug loss. This review focuses on ultrasound-triggered drug delivery by nanocarriers as a versatile, cost-efficient, non-invasive technique for improving tissue specificity and tissue penetration, and for achieving high drug concentrations at their intended site of action. It highlights aspects relevant for ultrasound-mediated drug delivery, including ultrasound parameters and resulting biological effects. Then, concepts in ultrasound-mediated drug delivery are introduced and a comprehensive overview of several types of nanoparticles used for this purpose is given. This includes an in-depth compilation of the literature on the various in vivo ultrasound-responsive drug delivery systems. Finally, toxicological and safety considerations regarding ultrasound-mediated drug delivery with nanocarriers are discussed.

Trends in Degradable Mesoporous Organosilica-Based Nanomaterials for Controlling Drug Delivery: A Mini Review

The last few years of enhancing the design of hybrid mesoporous organosilica nanoparticleshas allowed their degradation under specific pathologic conditions, which finally is showing a lightin their potential use as drug delivery systems towards clinical trials. Nevertheless, the issueof controlling the degradation on-demand at cellular level still remains a major challenge, even if ithas lately been addressed through the incorporation of degradable organo-bridged alkoxysilanesinto the silica framework. On this basis, this mini review covers some of the most recent examplesof dierent degradable organosilica nanomaterials with potential application in nanomedicine,from degradable non-porous to mesoporous organosilica nanoparticles (MONs), functionalized withresponsive molecular gates, and also the very promising degradable periodic mesoporous organosilicamaterials (PMOs) only consisting of organosilica bridges.