Ultrasound-induced vaporization of perfluorocarbon (PFC) nanodroplets can be used for triggered drug delivery. Nanodroplets of perfluorobutane (PFB) and perfluoropentane (PFP) can vaporize spontaneously at physiological temperature, which can cause off-target effects. Using high-boiling-point PFCs, such as perfluorohexane (PFH), can overcome this limitation. However, PFH requires higher peak negative pressures for vaporization, making its in vivo use challenging. We investigated the feasibility of reducing the vaporization pressure threshold by gold-coating lipid-encapsulated PFH nanodroplets (Au-PFH-ND). We synthesized PFH nanodroplets, and the gold-coating was confirmed by UV-visible spectra. The mass of gold per nanodroplet was 5.12×10-4 pg. The size distribution peaked at 200 nm and had a mean concentration of 2×1010 droplets/ml. Au-PFH-ND demonstrated excellent stability over 8 weeks. Ultrasound imaging in vitro was used to determine the pressure threshold for nanodroplet vaporization upon exposure to 2 MHz ultrasound. The vaporization threshold for Au-PFH-ND (3.29 ± 0.93 MPa) was significantly lower than uncoated PFH nanodroplets (PFH-ND, 6.19 ± 1.25 MPa). Au-PFH-ND had a similar pressure threshold to uncoated PFP nanodroplets (PFP-ND, 2.81 ± 1.08 MPa). These findings show that the Au-PFH-ND can be vaporized at a similar ultrasound pressure as PFP-ND. Increasing pulse duration from 2 to 60 cycles enhanced vaporization of Au-PFH-ND, demonstrating the dominant role of a thermal mechanism. Even when accounting for the total ultrasound on-time and effective peak negative pressure, longer bursts (i.e., more cycles per burst) were more effective in inducing vaporization, consistent with the role of localized heating around the gold coating rather than a purely probabilistic effect. Additionally, inertial and stable cavitation emissions were quantified. Au-PFH-ND exhibited a marginally lower inertial cavitation threshold and similar second harmonic emissions than PFH-ND, suggesting that cavitation could also have played a role in reducing the pressure threshold. These findings are a step towards employing gold-coated PFC nanodroplets for multimodal drug delivery.

Mesoporous silica-coated gold nanorod grafted with cisplatin prodrug on the surface enhances radiotherapy for cervical cancer via triple-strategy approach.

Liquid-gas phase-change nanoplatforms for ultrasound-mediated cancer theranostics☆

Hydrophobic surface modified calcium alginate fibers for preparing flame retardant and comfortable Janus fabrics.

Inhalable perfluorocarbon RNA nanocapsules overcome biological barriers to treat lung metastases.

The development of noninvasive, quantifiable molecular imaging probes using magnetic resonance imaging (MRI) is critical for advancing in vivo diagnostics. Previous work has demonstrated the development of perfluorocarbon (PFC)‐encapsulated silica nanoparticles named as FLAME (fluorine accumulated silica nanoparticles for MRI enhancement) for sensitive in vivo imaging using 19 F MRI. While FLAME shows excellent MR properties and application potential, its biocompatibility is yet to be enhanced. Herein, a lipid bilayer‐coated 19 F MRI nanoparticle (FLAME‐LB) is developed, which easily changes the surface components of nanoparticles by coating PFC‐loaded silica nanoparticles with a phospholipid membrane containing PEGylated lipids. Structural characterization confirmed the successful bilayer formation, and 19 F nuclear magnetic resonance (NMR)/MRI analyses demonstrated strong, concentration‐dependent fluorine signals. In vivo studies in mice reveal that FLAME‐LB accumulates in the liver shortly after intravenous injection, but exhibits significantly faster clearance than uncoated FLAME nanoparticles. This difference is attributed to the lipid bilayer and PEGylation, which promotes hepatobiliary elimination. These findings highlight the potential of the surface‐engineered FLAME‐LB as a biocompatible and tunable platform for 19 F MRI applications in biomedical imaging.

Perfluorocarbons (PFCs) as well as related gases such as sulfur hexafluoride (SF6) or nitrogen trifluoride (NF3) are examples of F-gases, a subclass of per- and polyfluoroalkyl substances (PFAS). F-gases are anthropogenic greenhouse gases with the highest global warming potentials known and thus contribute significantly to global warming. To reduce their amount in the atmosphere, selectively adsorbing materials would be beneficial, but such materials are rare. A homologous series of porous organic cages with fluorinated side-chains is synthesized and depending on the targeted gas as well as operating temperature, different cages have high selectivities for certain F-gases against N2, CO2, and O2. Within this series, new benchmark selectivities against, e.g., perfluoro propane (PFC-218) and perfluoro cyclobutane (PFC-318) have been achieved based on attractive fluorine-fluorine interactions. Furthermore, these interactions are exploited for the first time in the adsorption of sulfur hexafluoride and nitrogen trifluoride.

ABSTRACTHydrogel microparticles with different actives encapsulation have reliable efficacy in wound repair, and the challenge is to improve the active substance to improve the efficacy. Here, a novel ultrasonic responsive core‐shell microcapsule delivery system is proposed, which can simultaneously load traditional Chinese medicine sonosensitizer and oxygen synergistic effect to promote the healing of infected wounds. The microcapsule has a core of oxygen‐rich perfluorocarbon (PO) and a hydrogel shell with curcumin (PO/C‐MC). Ultrasound can trigger the release of oxygen from perfluorocarbon and stimulate the sonodynamic effect of curcumin, which is not only an anti‐inflammatory traditional Chinese medicine but also a sonosensitizer, thus realizing the synergistic treatment of traditional Chinese medicine and acoustic dynamics. Under the irradiation of low‐intensity ultrasound, PO/C‐MCs can effectively increase the oxygen concentration and enhance the antibacterial effect of sonodynamic therapy, synergizing with the anti‐inflammatory effect of traditional Chinese medicine to promote the rapid healing of chronic infected wounds. The study demonstrated that ultrasound‐responsive PO/C‐MCs microcapsules significantly enhanced the healing process of infected wounds in mice. Given these beneficial characteristics, PO/C‐MCs represent a promising therapeutic candidate with considerable potential for clinical application in managing chronic infected wounds.

Perfluorocarbon nanotechnologies for blood-brain barrier modulation: Enhancing drug delivery and neuroprotection.

In this study, a numerical investigation was conducted into the transport and splitting behavior of perfluorocarbon (PFC) bubbles within bifurcating arterial networks, with a focus on gas embolotherapy, a potential cancer treatment. A two-dimensional arterial model was used to examine how blood flow affects bubble dynamics. The volume of fluid (VOF) method in computational fluid dynamics (CFD) simulations was employed to model the interaction between capsular-shaped bubbles and blood flow. Multiple bifurcation angles, 60° and 90°, were analyzed, both with and without stenosis, to assess their impact on bubble movement and splitting phenomena. The results demonstrated that both bifurcation angle and stenosis significantly affected bubble behavior. In the 60° and 90° bifurcation vessels without stenosis, the bubble split homogeneously and traveled through the entire vessel path. However, in the 60° bifurcation vessel with stenosis, the bubble did not split homogeneously and passed through only one daughter artery. In contrast, the bubble split homogeneously in the 90° bifurcation vessel with stenosis. These findings provide valuable insights into how vessel geometry impacts bubble movement and splitting in blood and contribute to optimizing gas embolotherapy treatments.

Abstract Effective chemotherapy for glioblastoma (GBM) is severely limited by the impermeability of the blood-brain barrier (BBB). Although paclitaxel (PTX) demonstrates potent anti-glioma activity in vitro, its poor BBB penetration precludes its clinical use for GBM. We developed a novel PTX-loaded microbubble (PTX@MB) platform designed for targeted drug delivery to gliomas via low-intensity focused ultrasound (LIFU). PTX@MBs were fabricated using a perfluorocarbon (PFC) liquid core stabilized by Pluronic F-127, and their physicochemical properties were characterized. In vitro anti-tumor effects were evaluated using U87MG cells in both 2D culture and 3D spheroid models. For in vivo assessment, an orthotopic U87MG glioma mouse model was utilized. Following intravenous administration of PTX@MBs, LIFU was applied to the tumor region to induce localized drug release and transient BBB disruption. Therapeutic outcomes were evaluated by MRI, survival analysis, and histopathology. The synthesized PTX@MBs were spherical, with a high drug encapsulation efficiency of 89.1 ± 0.5%, and exhibited ultrasound-responsive drug release. In vitro, the combination of PTX@MBs and ultrasound exposure demonstrated dose-dependent cytotoxicity and significant inhibition of U87MG spheroid growth. In the orthotopic mouse model, the PTX@MB + LIFU treatment significantly suppressed tumor progression and prolonged median survival compared to the control group. While this treatment also showed a positive trend in efficacy over PTX alone, the difference did not reach statistical significance. This therapeutic benefit was achieved without notable systemic toxicity, and histopathological analysis confirmed a substantial reduction in tumor burden in the PTX@MB + LIFU group. This study demonstrates a clinically promising, ultrasound-responsive delivery system capable of overcoming the BBB for targeted paclitaxel delivery. The PTX@MB + LIFU platform effectively inhibits GBM growth in a preclinical model and represents a viable strategy for non-invasive, site-specific chemotherapy delivery in neuro-oncology.

The spin polarization-induced nuclear Overhauser effect (SPINOE), particularly at low field strengths, can increase nuclear spin polarization by several orders of magnitude relative to its thermal equilibrium value and offers a promising route to offset the inherently low polarization that limits ultra-low field nuclear magnetic resonance (NMR) spectroscopy and magnetic resonance imaging (MRI). In this study, we demonstrate the SPINOE-mediated polarization of oxygen-sensitive perfluorocarbons (PFC) by laser-polarized 129Xe gas at ultra-low magnetic field strengths. Low field provides several distinct advantages for SPINOE, such as more efficient polarization transfer in systems with slow molecular dynamics, and the ability to simultaneously detect both spin species, which enables a more direct and accurate observation of the spin polarization dynamics and its modulation by molecular oxygen. We begin by outlining the theoretical framework describing how SPINOE efficiency depends on field strength, correlation time, and the relaxation times of the involved nuclei, followed by experimental results demonstrating long-lasting polarization enhancement of oxygen-sensitive PFCs. Using a straightforward bubbling protocol to introduce hyperpolarized 129Xe into a PFC solution, we observed a 53-fold enhancement of the 19F NMR signal. This enhancement persisted for tens of seconds, well beyond the 19F relaxation time (< 10 s), enabling prolonged detection of 19F signals from oxygen-sensitive PFCs at ultra-low field.

Foam Fortification: Effect of Perfluorocarbon Gases on the Stability of Sclerosing Agent Foams.

Amphiphilic fluorinated Aza-BODIPY alleviates hypoxia in solid tumors and enhances the photodynamic efficacy for breast cancer.

ABSTRACT Perfluorocarbon (PFC) gas tracers perfluoromethylcyclohexane (PMCH) and perfluoro‐1,3‐dimethylcyclohexane (PDCH) were evaluated for CO 2 geo‐storage and enhanced oil recovery (EOR) applications under high‐temperature conditions. A novel detection method using a flame ionisation detector (FID) was employed as a cost‐effective and environmentally safer alternative to the conventional electron capture detector (ECD), overcoming associated regulatory and maintenance challenges. Thermal stability was assessed by aging the tracers with CO 2 at 120°C for 48 h, with gas chromatography–mass spectrometry (GC–MS) confirming no degradation. Adsorption studies revealed minimal adsorption with sandstone, and energy‐dispersive x‐ray spectroscopy (EDX) indicated no significant mineralogical alterations. Wettability tests confirmed a water‐wet environment with a contact angle of ≈52°, whereas interfacial tension remained stable at ≈56.45 mN/m. The minimum miscibility pressure (MMP) of CO 2 was determined at ≈1500 psi using a slim tube apparatus. Core flooding experiments on sandstone cores from the Rajasthan oilfield, India, were conducted to evaluate tracer transport behaviour. Breakthrough curves obtained from gas chromatography–FID analysis were used to derive swept pore volume, sweep efficiency, Lorentz coefficient and tortuosity. The findings confirm the thermal and chemical stability of PMCH and PDCH tracers, validating their application in reservoir characterisation and CO 2 monitoring. The FID‐based detection approach was proven effective and practical.

Thermally reversible supramolecular perfluorocarbon (PFC) gels are unique soft materials and have been gaining significant interest in many applications. Developing efficient low-molecular-weight organogelators for PFCs is an attractive field, but it remains challenging. This paper reports a highly efficient β-thioester-based gelator for the gelation of PFCs. The gelators are synthesized through click chemistry, using alkyl thiols and acrylates containing perfluoroalkyl chains, and have a diblock molecular structure that incorporates thioether and ester groups. In four typical PFCs (perfluorooctane, perfluorotributylamine, perfluoropropylene trimers, and perfluorodecalin), the gel properties of β-thioester-based gelators have been studied, achieving a low critical gel concentration (CGC) of only 0.3%-0.7% w/w. Comparative studies have shown that the high gelation efficiency arises from the formation of a fine fibrous structure in which the thioether group plays a crucial role, supported by the synergistic contribution of the ester group. In addition to the functional groups, the effect of alkyl chain length is also studied, revealing that the optimal chain length is n = 12. The achieved PFC gels are thermally reversible and have a storage modulus of 103-104 Pa in the 0.5-1.5% (w/w) concentration range. As we have demonstrated, these PFC gels are promising candidate materials for constructing temperature-responsive films that can switch the transmission of visible light.

Intravital lung imaging has been employed to study physiological and pathophysiological processes related to nanoparticle deposition in the alveolar lung, particularly in the context of air pollution and drug delivery. However, optical imaging depth is limited, often attributed to the refractive index (RI) mismatch at the alveolar air-tissue interface. To investigate this, we evaluated two complementary strategies. First, we demonstrated that eliminating the RI mismatch via partial liquid ventilation with oxygenated perfluorocarbon (PFC) did not enhance the imaging depth. A second approach, utilizing exvivo optical tissue clearing (with RI matching), was only successful in improving imaging penetration depth if it included removal of scattering lipids such as pulmonary surfactant. Nevertheless, partial liquid ventilation with PFC invivo enabled the homogeneous delivery of nanoparticles to the alveoli, allowing real-time observation of their interactions with lung epithelium. This finding opens new avenues for studying inhaled particulates and optimizing inhalation-based drug delivery.

ABSTRACT Paulownia wood has a significant economic value as it is a fast-growing tree species. Fluorocarbon (FC) resin impregnation with heat treatment (HT) at different levels (15% FC and 25% FC treatments at 150 and 160 °C) was used to minimise the adverse effect of the treatment on the properties of paulownia wood, particularly mechanical properties. Water contact-angle measurements showed a significant increase in hydrophobicity with the HT and FC treatments. Surface roughness analysis showed a decrease in roughness with the heat treatment and FC addition. FC treatment improved surface hydrophobicity and colour properties of the heat-treated wood. The control specimen had the highest modulus of rupture (MOR) of 42 MPa and modulus of elasticity (MOE) of 1935 MPa, but had lower compressive strength than the 15% FC/150 °C treated specimens. Specimens with 15% FC at 150 °C had better mechanical properties (MOR 38 MPa, MOE 1900 MPa; compressive strength: 32.3 MPa) than those treated with HT-150 alone. Increasing FC resin content in both heat treatments decreased the mechanical properties. Overall, treating paulownia wood with 15% FC resin and heat treatment at 150 °C produced better MOE, MOE, and compressive strength than heat treatment alone.

BackgroundIn vivo dosimetry is a crucial component of ensuring accurate and safe radiation therapy (RT) delivery, but many existing techniques face challenges such as low signal‐to‐noise ratio (SNR), which can limit their clinical applicability.PurposeIn this study, we investigate a novel contrast agent sensitive to megavoltage (MV) radiation in vitro, ultimately aiming for in vivo dosimetry.MethodsVaporizable exoskeletal droplets were engineered to phase‐change into ultrasound‐responsive microbubbles upon exposure to MV photon radiation. These droplets comprised a hydrocarbon (HC) exoskeleton doped with gold nanoparticles (GNPs) surrounding a liquid fluorocarbon (FC) core. Radiation absorbed by the GNPs induced localized heating, leading to vaporization of the FC phase. Droplet vaporization in response to clinical MV radiation was observed under a microscope at varying temperatures. Individual droplet samples were heated to temperatures ranging from 31 to 34°C, incubated for 8 min, then irradiated with a 5 × 5‐cm2 10 × flattening filter free (FFF) photon beam (Varian Truebeam) at a dose rate of 24 Gy/min to measure radiation‐induced vaporization. T‐tests (α = 0.05) were performed comparing the number of bubbles generated from irradiated droplets with GNPs compared to irradiated droplets without GNPs and nonirradiated droplets with GNPs.ResultsGNP‐doped exoskeletal droplets exhibited enhanced vaporization in response to MV radiation compared to heating alone. Vaporization increased with radiation dose, and the dose threshold required for vaporization decreased with rising temperature. Specifically, at 31 and 34°C, the dose required to vaporize 10% of bubbles (D10%) decreased from 22 to 4 Gy, and that required to vaporize 50% of bubbles (D50%) decreased from 67.5 to 36 Gy, respectively. The activation threshold at body temperature (37°C) was extrapolated to be clinically relevant, with D10% activation estimated to be 0.41 Gy. At T = 32 to 34°C, we showed statistically significant radiation‐induced vaporization of droplets with GNPs compared to non‐irradiated droplets with GNPs (p‐values from 0.0003 to 0.0232). Irradiation of droplets lacking GNPs did not induce notable vaporization.ConclusionsGNP‐doped exoskeletal droplets were demonstrated to exhibit enhanced vaporization upon exposure to clinically relevant MV x‐ray radiation doses compared to thermal activation alone in the absence of radiation. This is the first step in the development of an x‐ray acoustic contrast agent for dosimetry of RT in vivo.

19F MR Imaging of Dule Lung Cancer Models with Two Administration Methods of PFC Nanoparticles.