Over the past few decades, there has been an increasing interest in the fabrication of complex high-resolution three-dimensional (3D) architectures at micro/nanoscale. These architectures can be obtained through conventional microfabrication methods including photolithography, electron-beam lithography, femtosecond laser lithography, nanoimprint lithography, etc. However, the applications of these fabrication methods are limited by their high costs, the generation of various chemical wastes, and their insufficient ability to create high-aspect-ratio 3D structures. High-resolution 3D printing has recently emerged as a promising solution, as it is capable of building multifunctional 3D constructs with optimal properties. Here we present a review on the principles and the recent advances of high-resolution 3D printing techniques, including two-photon polymerization (TPP), projection microstereoLithography (PµSL), direct ink writing (DIW) and electrohydrodynamic printing (EHDP). We also highlight their typical applications in various fields such as metamaterials, energy storage, flexible electronics, microscale tissue engineering scaffolds and organ-on-chips. Finally, we discuss the challenge and perspective of these high-resolution 3D printing techniques in technical and application aspects. We believe that high-resolution 3D printing will eventually revolutionize the microfabrication processes of 3D architectures with high product quality and diversified materials. It will also find applications in a wide scope.

Moving micron scale objects are strongly coupled to each other by hydrodynamic interactions. The strength of this coupling decays as the inverse particle separation when the two objects are sufficiently far apart. It has been recently demonstrated that the reduced dimensionality of thin fluid layer gives rise to longer ranged, logarithmic coupling. Using holographic tweezers we show that microrods display both behaviors interacting like point particle in 3D at large distance and like point particles in 2D for distances shorter then their length. We derive a simple analytical expression that fits remarkably well our data and further validate it with finite element analysis.

Electrohydrodynamic (EHD) printing is a newly emerging additive manufacturing strategy for the controlled fabrication of three-dimensional (3D) micro/nanoscale architectures. This unique superiority makes it particularly suitable for the biofabrication of artificial tissue analogs with biomimetic structural organizations similar to the scales of native extracellular matrix (ECM) or living cells, which shows great potentials to precisely regulate cellular behaviors and tissue regeneration. Here the state-of-the-art advancements of high-resolution EHD bioprinting were reviewed mainly including melt-based and solution-based processes for the fabrication of micro/nanoscale fibrous scaffolds and living tissues constructs. The related printing materials, innovations on structure design and printing processes, functionalization of the resultant architectures as well as their effects on the mechanical and biological properties of the EHD-printed structures were introduced and analyzed. The recent explorations on the EHD cell printing for high-resolution cell-laden microgel patterning and 3D construct fabrication were highlighted. The major challenges as well as possible solutions to translate EHD bioprinting into a mature and prevalent biofabrication strategy were finally discussed.

Based on the safety, efficacy, and patient preferences, the 32-tablet RF-NaP regimen was superior to the 40-tablet RF-NaP and NaP regimen for colon cleansing prior to colonoscopy.

Extraction of high-purity phosphate (P) from source-separated urine has attracted growing interest, given its potential economic and environmental benefits. In this study, we present an innovative strategy for selectively separating P from synthetic urine containing a high concentration of Cl − , simply by adjusting the charging and discharging processes of a flowelectrode capacitive deionization (FCDI) unit. During the charging process, both P and Cl − will be transported to the anode chamber and be adsorbed by the charged carbon particles. The inevitable Faradaic reactions induced the generation of H + and led to the conversion of charged P ions into uncharged H 3 PO 4 and spontaneous desorption into the electrolyte. When the electrode polarity is reversed, constantly charged species like Cl − would be mostly pushed back into the spacer chamber, whereas neutral H 3 PO 4 was expected to be selectively trapped in the anode chamber due to sluggish pH variations (particularly when using a higher carbon content), forming a P-rich solution. Under the optimal operating conditions (i.e., carbon content of 5 wt %, charging and discharging current densities of 10 and −15 A/m 2 , respectively, and charging and discharging current times of 120 and 30 min, respectively), a stable recovery efficiency (164 mg/L per cycle) and selectivity (ρ > 2, compared to Cl − ) of P were attained at a relatively low level of electric energy consumption. Results demonstrated that FCDI could be a promising technology for efficient P removal and recovery from source-separated urine without the consumption of additional chemicals.

An electrohydrodynamic printing strategy is presented to fabricate microscale flexible features with tunable conductive properties based on in situ reactive inks.

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This study aimed to explore the spectrum-effect relationships between high-performance liquid chromatography fingerprints and the uric acid-lowering activities of chicory. Chemical fingerprints of chicory samples from ten different sources were determined by high-performance liquid chromatography, and then investigated by similarity analysis and hierarchical clustering analysis. Pharmacodynamics experiments were conducted in animals to obtain the uric acid-lowering activity information of each chicory sample. The spectrum-effect relationships between chemical fingerprints and the uric acid-lowering activities of chicory were established by canonical correlation analysis. The structures of potential effective peaks were identified by liquid chromatography with tandem mass spectrometry. The results showed that a close correlation existed between the spectrum and effect of chicory. Aesculin, chlorogenic acid, chicoric acid, isochlorogenic acid A/B/C and 13,14-seco-stigma5(6),14(15)-diene-3α-ol might be the main effective constituents. This work provides a general model of the combination of high-performance liquid chromatography and uric acid-lowering activities to study the spectrum-effect relationships of chicory, which can be used to discover the principle components responsible for the bioactivity.