Stimuli‐Responsive Nanocarriers for Transcytosis‐Based Cancer Drug Delivery

Significant challenges persist in enhancing the delivery efficiency of tumor nanomedicines, predominantly due to the difficulty of successfully surpassing pathophysiological barriers. Enhancing tumor penetration of nanomedicines in such conditions represents a pivotal goal in advancing anticancer nanotherapeutics. Transcytosis emerges as a promising solution in this context, addressing the limitations of passive drug delivery. By harnessing diverse stimuli to induce transcytosis, nanocarriers can achieve precise drug delivery and deep tumor penetration, resulting in high therapeutic efficacy and reduced systemic exposure to the therapeutic compound. This review briefly examines various stimuli‐responsive nanosystems and offers an overview and outlook on the development of stimuli‐responsive nanocarriers for transcytosis‐based cancer drug delivery, aiming to provide informative insights for the design of nanomedicines capable of deep tissue penetration and enhanced therapeutic efficacy

Enhanced Passive GNSS-Based Radar Imaging Based on Coherent Integrated Multi-Satellite Signals

Weak reflected signal is one of the main problems in a recent developing remote sensing tool—passive GNSS-based radar (GNSS radar). To address this issue, an enhanced GNSS radar imaging scheme on the basis of coherently integrating multiple satellites is proposed. In the proposed scheme, to avoid direct signal interference at surveillance antenna, the satellites that used as transmission of opportunity are in backscattering geometry model. To coherently accumulate echo signal magnitudes of the scene center in the targeted sensing region illuminated by the selected satellites, after performing the paralleled range compressions, a coordinates alignment operator is performed to the respective range domains, in which, pseudorandom noise (PRN) code phases are aligned. Thereafter, the coordinates aligned range compressed signals of the selected satellites are coherently integrated along azimuth domain so that imaging gain is improved and azimuth processing can be accomplished in only one state operation. The theoretical analysis and field proof-of-concept experimental results indicate that compared to both conventional bistatic imaging scheme and the state-of-the-art multi-image fusion scheme, the proposed scheme can provide a higher imaging gain; compared to the state-of-the-art multi-image fusion scheme, the proposed scheme has a less computational complexity and faster algorithm speed

Encapsulation of Volatile Monoterpene Fragrances in Mesoporous Organosilica Nanoparticles and Potential Application in Fruit Preservation

In this work, we synthesized mesoporous silica nanoparticles (MSNs) and periodic mesoporous organosilica nanoparticles containing bridging groups of ethylene (E-PMO) and phenylene (P-PMO) and compared their adsorption properties using D-limonene (Lim), myrcene (Myr), and cymene (Cym) as model guest molecules. For the selected nanoparticles of ~100 nm in diameter, the loading capacity to the volatile fragrances was in the order of P-PMO < E-PMO < MSN, consistent with the trend of increasing total pore volume. For example, P-PMO, E-PMO, and MSN had a Lim uptake of 42.2 wt%, 47.3 wt%, and 62.7 wt%, respectively, which was close to their theoretical adsorption capacity. Under isothermal thermogravimetric analysis conditions (30 °C, a N2 flow of 1 mL min−1), the lowest fragrance release of ~56% over 24 h was observed for P-PMO, followed by E-PMO (74–80%), and MSN (~89%). The release kinetics of the fragrant molecules from MSN and PMO materials can be well described by first-order and Weibull models, respectively. Moreover, the incorporation of Lim-loaded P-PMO NPs in an aqueous solution of regenerated silk fibroin provided a composite coating material suitable for perishable fruit preservation. The active layer deposited on fruit peels using dip coating showed good preservation efficacy, enabling the shelf-life of mangoes in a highly humid and hot atmosphere (30–35 °C, 75–85% RH) to be extended to 6 days

Esterase-Activated Charge-Reversal Polymer for Fibroblast-Exempt Cancer Gene Therapy

Selective gene expression in tumors via responsive dissociation of polyplexes triggered by intracellular signals is demonstrated. An esterase-responsive charge-reversal polymer mediates selective gene expression in the cancer cells high in esterases over fibroblasts low in esterase activity. Its gene therapy with the TRAIL suicide gene effectively induces apoptosis of HeLa cells but does not activate fibroblasts to secrete WNT16B, enabling potent cancer gene therapy with few side effects

Gd³⁺-1,4,7,10-Tetraazacyclododecane-1,4,7-triacetic-2-hydroxypropyl-β-cyclodextrin/Pluronic Polyrotaxane as a Long Circulating High Relaxivity MRI Contrast Agent

A multivalent magnetic resonance imaging agent based on a 2-hydroxypropyl-β-cyclodextrin (HPCD):Pluronic F127 polyrotaxane carrier has been synthesized, and its blood pool contrast properties have been characterized. This Gd³⁺-DO3A-HPCD/Pluronic polyrotaxane construct is shown to circulate for more than 30 min and provide >100-fold vascular enhancement relative to the monomeric Gd³⁺-DO3A-HPCD control that is rapidly cleared via the kidney. The high <i>r</i>₁ relaxivity at 37 °C (23.83 mM^–1 s^–1 at 1.5 T; 34.08 mM^–1 s^–1 at 0.5 T), extended blood circulation, well-known pharmacology of the polyrotaxane precursors, and absence of acute toxicity make it a highly attractive blood pool contrast agent candidate