Microparticles with uniform anisotropic structures are widely used in physical, chemical, and biological fields owing to their ability to combine multiple functions on a micro-scale. Here, a ...microfluidic emulsion-based external gelation method was demonstrated for the first time to produce monodisperse Janus calcium alginate (Ca-alginate) hydrogel microparticles consisting of two compartments. This approach provided a fast reaction condition under which we could prepare magnetic Janus Ca-alginate microparticles with diameters ranging from 148 to 179 μm and a coefficient of variation (CV) less than 4%. Moreover, the boundaries between the two compartments were clear. In addition, the volume fraction of each compartment could be adjusted by varying the flow rate ratio between two dispersed phases. Next, we produced fluorescent Janus beads and magnetic-fluorescent Janus beads with an average diameter of ∼150 μm (CV < 4.0%). The magnetic Janus hydrogel microparticles we produced could be manipulated by applying a magnetic field to achieve self-assembly, rotation, and accumulation. Magnetic Janus hydrogel microparticles are also capable of mammalian cell encapsulation with good cell viability. This article presents a simple and stable approach for producing monodisperse bi-compartmental Janus hydrogel microparticles that could have great potential for application in physical, biochemical, and biomedical fields.
•A microfluidic process for producing spherical Ca-alginate hydrogels is developed.•A calcium chloride emulsion reactant is used for on-chip external gelation.•Monodisperse highly spherical hydrogels ...are obtained under optimized conditions.•The synthesis of hydrogels coated with magnetic nanoparticles is also demonstrated.
Alginate-based hydrogels are widely used in the biomedical and chemical fields, and their size and shape are significant to their applications like drug delivery and cell encapsulation. Here, we report a microfluidic external gelation process using an on-chip calcium chloride (CaCl2) emulsion reactant for producing highly spherical calcium alginate (Ca-alginate) hydrogel particles. The microfluidic channels were two serial cross-junctions fabricated on quartz glass. Monodisperse sodium alginate (Na-alginate) droplets with diameters greater or smaller than the opening (ranging from 176 μm to 225 μm) with a coefficient of variation (CV) less than 3% were successfully generated at the upstream cross-junction; they then reacted with the CaCl2 emulsion at the downstream cross-junction, forming Ca-alginate hydrogels. The effects of the fraction of the aqueous phase in the reactant CaCl2 emulsion and the flow rates of continuous and emulsion phases on the roundness of the obtained hydrogels were studied. By optimizing the parameters above, monodisperse spherical hydrogel particles were obtained with diameters ranging from 147 μm to 176 μm with CVs around 5%. The synthesis of magneto-responsive hydrogels with asymmetric Fe3O4 coatings was also demonstrated.
Transient receptor potential (TRP) channels are predominantly distributed in both somatic and visceral sensory nervous systems and play a crucial role in sensory transduction. As the largest visceral ...organ system, the gastrointestinal (GI) tract frequently accommodates external inputs, which stimulate sensory nerves to initiate and coordinate sensory and motor functions in order to digest and absorb nutrients. Meanwhile, the sensory nerves in the GI tract are also able to detect potential tissue damage by responding to noxious irritants. This nocifensive function is mediated through specific ion channels and receptors expressed in a subpopulation of spinal and vagal afferent nerve called nociceptor. In the last 18 years, our understanding of TRP channel expression and function in GI sensory nervous system has been continuously improved. In this review, we focus on the expressions and functions of TRPV1, TRPA1, and TRPM8 in primary extrinsic afferent nerves innervated in the esophagus, stomach, intestine, and colon and briefly discuss their potential roles in relevant GI disorders.
Metabolic reprogramming greatly contributes to the regulation of macrophage activation. However, the mechanism of lipid accumulation and the corresponding function in tumor-associated macrophages ...(TAMs) remain unclear. With primary investigation in colon cancer and confirmation in other cancer models, here we determine that deficiency of monoacylglycerol lipase (MGLL) results in lipid overload in TAMs. Functionally, macrophage MGLL inhibits CB2 cannabinoid receptor-dependent tumor progression in inoculated and genetic cancer models. Mechanistically, MGLL deficiency promotes CB2/TLR4-dependent macrophage activation, which further suppresses the function of tumor-associated CD8+ T cells. Treatment with CB2 antagonists delays tumor progression in inoculated and genetic cancer models. Finally, we verify that expression of macrophage MGLL is decreased in cancer tissues and positively correlated with the survival of cancer patients. Taken together, our findings identify MGLL as a switch for CB2/TLR4-dependent macrophage activation and provide potential targets for cancer therapy.
Hydrogel microparticles, generally accepted as significant green materials, have been widely used in chemical, biological, and biomedical fields owing to their excellent biocompatibility, ...biodegradability, and non-cytotoxicity. Among these, non-spherical hydrogel microparticles with diverse shape anisotropy have great potential in applications such as drug delivery, cellular interaction, micromotors, etc. Benefiting from their shapes, their functionalities in such fields cannot be satisfied by the typical spherical types. Recently, microfluidics with precise control and domination of fluids at microflow sizes has emerged as a powerful method for synthesizing shape-controllable hydrogel microparticles with good monodispersity and unique morphology. In this review, we tried to provide an overview of the production of non-spherical microparticles composed of green hydrogel materials, emphasizing the microfluidic approaches. Furthermore, a brief introduction to their current applications is also presented.
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•The commonly and recently used microfluidic methods for preparing non-spherical hydrogel microparticles are demonstrated.•Microfluidics generation non-spherical hydrogel particles have been classified and compared.•The recently reported applications of NSHPs of various shapes in specific fields are discussed.•The outlook for the microfluidic synthesis of NSHPs is discussed.
In the ZINC20 database, with the aid of maximum substructure searches, common substructures were obtained from molecules with high-strain-energy and combustion heat values, and further provided ...domain knowledge on how to design high-energy-density hydrocarbon (HEDH) fuels. Notably, quadricyclane and syntin could be topologically assembled through these substructures, and the corresponding assembled schemes guided the design of 20 fuel molecules (ZD-1 to ZD-20). The fuel properties of the molecules were evaluated by using group-contribution methods and density functional theory (DFT) calculations, where ZD-6 stood out due to the high volumetric net heat of combustion, high specific impulse, low melting point, and acceptable flash point. Based on the neural network model for evaluating the synthetic complexity (SCScore), the estimated value of ZD-6 was close to that of syntin, indicating that the synthetic complexity of ZD-6 was comparable to that of syntin. This work not only provides ZD-6 as a potential HEDH fuel, but also illustrates the superiority of learning design strategies from the data in increasing the understanding of structure and performance relationships and accelerating the development of novel HEDH fuels.
Multimethods of simulation and experiment have been performed to investigate the interaction between glycidyl azide polymer (GAP) matrix and insensitive energetic plasticizers ...N-butyl-N-(2-nitroxy-ethyl)nitramine (Bu-NENA) and bis(2,2-dinitropropyl)formal/acetal (BDNPF/A). To start with, the blending energy distribution and Huggins parameters have been calculated, indicating fine miscibility between the GAP matrix and both plasticizers. The solubility parameter and binding energies show better compatibility between Bu-NENA and the GAP matrix than BDNPF/A, owing to stronger interactions. The interaction mechanism includes both hydrogen bonds and van der Waals forces. The low field NMR physical cross-link density and dynamic rheological behaviors imply larger disentanglement effect of Bu-NENA in the GAP matrix. The dynamic mechanical performance of elastomers show lower glass transition temperature of GAP/Bu-NENA blends, as supportive proof of stronger interactions between the GAP matrix and Bu-NENA in comparison with BDNPF/A.
Abstract
In this paper, twelve 1,3-dinitrohexahydropyrimidine-based energetic compounds were designed by introducing various explosopheres into hexahydropyrimidine skeleton. Their geometric and ...electronic structures, heats of formation (HOFs), energetic performance, thermal stability and impact sensitivity were discussed. It is found that the incorporation of electron-withdrawing groups (–NO
2
, –NHNO
2
, –N
3
, –CH(NO
2
)
2
, –CF(NO
2
)
2
, –C(NO
2
)
3
) improves HOFs of the derivatives and all the substituents contribute to enhancing the densities and detonation properties (
D
,
P
) of the title compounds. Therein, the substitution of –C(NO
2
)
3
features the best energetic performance with detonation velocity of 9.40 km s
−1
and detonation pressure of 40.20 GPa. An analysis of the bond dissociation energies suggests that N–NO
2
bond may be the initial site in the thermal decompositions for most of the derivatives. Besides, –ONO
2
and –NF
2
derivatives stand out with lower impact sensitivity. Characters with striking detonation properties (
D
= 8.62 km s
−1
,
P
= 35.08 GPa;
D
= 8.81 km s
−1
,
P
= 34.88 GPa), good thermal stability, and acceptable impact sensitivity (characteristic height
H
50
over 34 cm) lead novel compounds 5,5-difluoramine-1,3-dinitrohexahydropyrimidine (K) and 5-fluoro-1,3,5-trinitrohexahydropyrimidine (L) to be very promising energetic materials. This work provides the theoretical molecular design and a reasonable synthetic route of L for further experimental synthesis and testing.
Artificial intelligence technology shows the advantages of improving efficiency, reducing costs, shortening time, reducing the number of staff on site and achieving precise operations, making ...impressive research progress in the fields of drug discovery and development, but there are few reports on application in energetic materials. This paper addresses the high safety risks in the current nitrification process of energetic materials, comprehensively analyses and summarizes the main safety risks and their control elements in the nitrification process, proposes possibilities and suggestions for using artificial intelligence technology to enhance the "essential safety" of the nitrification process in energetic materials, reviews the research progress of artificial intelligence in the field of drug synthesis, looks forward to the application prospects of artificial intelligence technology in the nitrification of energetic materials and provides support and guidance for the safe processing of nitrification in the propellants and explosives industry.
Dinitropyrazole is an important structure for the design and synthesis of energetic materials. In this work, we reported the first comparative thermal studies of two representative ...dinitropyrazole-based energetic materials, 4-amino-3,5-dinitropyrazole (LLM-116) and its novel trimer derivative (LLM-226). Both the experimental and theoretical results proved the active aromatic N-H moiety would cause incredible variations in the physicochemical characteristics of the obtained energetic materials. Thermal behaviors and kinetic studies of the two related dinitropyrazole-based energetic structures showed that impressive thermal stabilization could be achieved after the trimerization, but also would result in a less concentrated heat-release process. Detailed analysis of condensed-phase systems and the gaseous products during the thermal decomposition processes, and simulation studies based on ReaxFF force field, indicated that the ring opening of LLM-116 was triggered by hydrogen transfer of the active aromatic N-H moiety. In contrast, the initial decomposition of LLM-226 was caused by the rupture of carbon-nitrogen bonds at the diazo moiety.
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