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Purpose: Cervical cancer (CC) is a highly vascularized tumor with abundant abnormal blood vessel, which could be targeted by therapeutic strategies. Poly(L-glutamic acid)- g -methoxy poly(ethylene glycol)/combretastatin A4 (CA4)/BLZ945 nanoparticles (CB-NPs) have shown great potential as nano vascular disrupting agents (VDAs) in the realm of synergistic cancer therapy., Methods: In this study, we investigated the nanocharacteristics of CB-NPs, focusing on active pharmaceutical ingredients (API), as well as lyophilized samples combining API with protective agents (PAs). The in vivo efficacy of final sample (API + PAs) was evaluated., Results: The assembled sphere of API with complex core and thin-shell structure was confirmed. PAs were found to significantly influence in vivo efficacy. Collaborative efforts between API and PAs, namely mannitol and lactose, resulted in the most promising lyophilized sample, ie, the final sample (FS2) for CC therapy. Impressively, FS2 demonstrated an exceptional 100% cure rate on the CC U14-bearing mice model., Conclusion: FS2 has provided significant insights for cervical cancer therapy. It is also crucial to develop a comprehensive evaluation strategy for the formulation of nanomedicine, which has the potential to serve as a guideline for future clinical trials., Competing Interests: The authors report no conflicts of interest in this work., (© 2023 Guo et al.)

Square shaped twinned guanine microplatelets with high symmetry are assembled into highly ordered layered patterns and function as image-forming mirrors in scallop eyes. However, the twinning mechanism of twinned guanine microplatelets is still unclear. Herein, the eyes of juvenile Yesso scallops were investigated to understand the formation mechanism of the twinned β-form anhydrous guanine (β-AG) microplatelets exposing the (100) plane. We found α form anhydrous guanine (α-AG) and single-crystal β-AG nanoplatelets in the very early stage of the eyes of the juvenile scallops, while the α-AG was supposed to be formed via amorphous guanine during the sample preparation process. Besides β-AG and α-AG, amorphous guanine was found in the eyes of juvenile scallops with a size of 2.5 mm according to the Raman spectra. A formation mechanism was proposed for the biogenic twinned β-AG platelets. Firstly, amorphous guanine is formed as an intermediate phase, which transforms into single crystalline β-AG nanoplatelets, or dissolves and recrystallizes to single crystalline β-AG nanoplatelets. Then, a second layer of β-AG forms on the top of the original single crystalline β-AG nanoplatelets, forming twinned β-AG nanoplatelets with two c axes with a certain angle, 83° or 14°. Each layer of the β-AG nanoplatelets is calculated to be about 14 ± 2 nm. This is the first time the twinning mechanism of biogenic twinned β-AG microplatelets is reported. Uncovering the formation mechanism of twinned platelets of organic crystals may shed light on the formation of functional synthetic twinned organic crystals in laboratories. [ABSTRACT FROM AUTHOR]

Biogenic twinning β-phase anhydrous guanine nanoplatelets are utilized as optical materials in organisms. However, it is still a puzzle how to produce crystalline guanine platelets in aqueous solutions since guanine has a low solubility in water. Herein, the controlled synthesis of twinning guanine nanoplatelets was realized for the first time in an aqueous solution in the presence of poly(1-vinylpyrrolidone-co-vinyl-acetate) via ammonia volatilization. The synthesized rectangular twinning guanine nanoplatelets with an exposed (100) face were β-form anhydrous guanine (β-AG), and the twinning angle of the two c-axes was about 83°, similar to the biogenic twinning β-AG nanoplatelets. The length and thickness of the twinning β-AG nanoplatelets were about 2 μm and 42 ± 3 nm, respectively. There were about five to seven layers observed for the synthesized twinning β-AG nanoplatelets, with each layer being as thin as 6 ± 2 nm. It was proposed that amorphous guanine particles are formed as intermediate precursors, which dissolve and recrystallize to single-crystalline β-AG nanoplatelets, and then multilayered twinning β-AG nanoplatelets are formed via π–π interaction with the assistance of the guanine-quartet assembly. The obtained twinning β-AG exhibited a high reflection intensity in the visible and near infrared region and a brilliant pearlescent luster, indicating that they could potentially be applied as optical materials. This work provides a new design strategy to synthesize particular organic molecular crystals with low solubility in water and a novel formation mechanism for twinning organic crystals. [ABSTRACT FROM AUTHOR]

Two disparate types of nano-fuels comprised of N-tetradecane (C14) with carbon nanotubes (CNT) and cerium dioxide (CeO2) nanoparticles were prepared, and their main physical parameters were compared. The visualized evaporation experiment of single pendant droplet was conducted at the environment temperatures from 100 ℃ to 200 ℃, and the effects of nanoparticles' concentration, size, and properties on the droplet evaporation performances were interpreted. It was found that the droplet evaporation process of different types of nano-fuels followed the classical D2-law well in the definite temperature range. However, nanoparticles have completely inverse effects on the droplet evaporation under low and high temperatures. At 100 ℃, due to the intensified surface tension and viscosity, the pendant nano-fuel droplets evaporated more slowly than C14 droplets, and the evaporation restraint was enhanced with the increase of nanoparticles' concentration. However, when the environment temperature was over 150 ℃, the droplet evaporation rate of nano-fuels was higher than that of C14, and it rose up with the increase of nanoparticles' concentration. At the same concentration, the droplet evaporation rate declined with the increase of the particle size. In addition, the role of CNT in enhancing the droplet evaporation was more pronounced. [ABSTRACT FROM AUTHOR]

A new nanocomposite of l-tryptophan functionalized graphene-supported platinum nanoparticles (l-Trp-rGO@PtNPs) was synthesized utilizing a facile ultrasonic method viaπ–π conjugate action between graphene-supported platinum nanoparticles and l-tryptophan (l-Trp) molecules. The prepared nanomaterial, which dispersed well in water and presented excellent conductivity, was modified on a glassy carbon electrode (l-Trp-rGO@PtNPs/GCE) for the chiral sensing of DOPA enantiomers. The immobilization process of l-Trp-rGO@PtNPs/GCE was characterized by cyclic voltammetry, electrochemical impedance spectroscopy, scanning electron microscopy, ultraviolet-visible (UV-vis) spectrometry and Raman spectroscopy. The electrochemical reactions of DOPA enantiomers were investigated via differential pulse voltammetry. The proposed electrochemical method showed excellent enantiospecificity for DOPA enantiomers and exhibited a stronger enantiospecificity for d-DOPA. In addition, the experimental parameters such as the concentration, the amount of l-Trp-rGO@PtNPs and the pH values were optimized. Under optimum conditions, the linear response ranges for the discrimination of DOPA were from 5.0 × 10−8 to 5.0 × 10−3 mol L−1 with a detection limit of 1.7 × 10−8 mol L−1 (S/N = 3). [ABSTRACT FROM AUTHOR]

Optical manipulation is a non-contact and non-destructive method to capture and manipulate micro/nano particles, biological macromolecules and cells with application of optical forces. With the rapid development of optical manipulation, various kinds of optical fiber tips have been presented and demonstrated in recent years. In this letter, a novel structure of optical fiber tip with an imbedded hollow cavity is presented. The electric field distribution of the fiber tip and the influence of cavity geometry are simulated with finite-difference time-domain method. The unique advantage is that the electric field intensity will be significantly enhanced when the fiber tip is filled with high refractive index medium in the cavity, which brings the potential to generate a three-dimensional optical trap for particles. Through experiments, we also demonstrate that the velocity of the particles driven by the optical force has a quadratic relationship with the laser power. The relationship can be used in microfluidic technology to measure the velocity of micro fluid. And the balance between the scattering force and the fluid force can be used to study non-invasive migration of particles. [ABSTRACT FROM AUTHOR]

Nano-fuel, as an appealing alternative, provides a new opportunity to promote engine performances. The surface tension is a vital factor affecting spray and evaporation of fuel. In this study, fuel blends containing 20 and 50 nm particles of CNT, CeO 2 and Co 3 O 4 with different mass concentrations (i.e. 50, 100 and 150 mg/L) were prepared by the two-step method, in which diesel worked as the base fuel and CTAB served as the surfactant. The surface tension of nano-fuel was determined experimentally at 10–140 °C based on the pendant drop method, and the effects of mass concentration, particle size, nanoparticle types and temperature on the surface tension of nano-fuel were analyzed. It is revealed that the nano-fuel had higher surface tension than diesel and it increased with the increase in mass concentration or particle size, while decreased linearly with the rise of temperature. Among three types of nano-fuels, CNT nano-fuels had the maximum surface tension, which is followed by CeO 2 nano-fuels and then Co 3 O 4 nano-fuels. [Display omitted] • Surface tension was determined by the pendent droplet method. • Surface tension was higher for nano-fuel due to particle-fuel interactions. • Surface tensions of disparate types of nano-fuels were compared. • Nano-fuels' surface tension increased with higher concentration and larger size. • Nano-fuels' surface tension reduced with the rise of temperature. [ABSTRACT FROM AUTHOR]

[Display omitted] • Nano-fuel evaporation was suppressed at 400 °C but promoted at 700 °C. • Nano-fuel evaporation deviated the D 2-law at 700 °C owing to micro-explosion. • Nano-fuel evaporation was greatly affected by nanoparticles' concentration and size. • Micro-explosion was strengthened by nanoparticles in fuel. • On a whole, CNT nano-fuel evaporated faster than CeO 2 nano-fuel. To investigate the effect of nanoparticles on the evaporation evolution of nano-fuels and reveal the mechanism of heterogeneous heat and mass transfer induced by the dispersion of nanoparticles, carbon nanotubes and CeO 2 nano-fuels with different mass concentrations and particle sizes were prepared based on the two-step method and inspected using a laser particle size analyzer. An evaporation visualization apparatus for a single suspended droplet and an image processing technology were utilized to study the evaporation of diesel and nano-fuels at 400 and 700 °C. At 400 °C, the evaporation of diesel and nano-fuel droplets accorded with the D 2-law and can be categorized as constant-volume and quasi-steady evaporation stages. The addition of nanoparticles suppressed the evaporation of fuel droplet and increasing the mass concentration or particle size can intensify the extent of suppression. At 700 °C, however, the micro-explosion of droplets occurred, and the variation in the droplet diameter did not conform with the D 2-law. Evaporation can be categorized into the constant-volume and fluctuating evaporation stages. Nanoparticles, as heterogeneous nucleation sites, enhanced the expansion and micro-explosion intensities, thereby promoting the fuel droplet evaporation. An increase in the mass concentration or a decrease in the particle size can promote evaporation significantly. [ABSTRACT FROM AUTHOR]