An oxygenating colloidal bioink for the engineering of biomimetic tissue constructs

Ensuring a sufficient oxygen supply is pivotal for the success of bioprinting applications since it fosters tissue integration and natural regeneration.Variation in oxygen concentration among diverse tissues necessitates the precise recreation of tissue-specific oxygen levels in imprinted constructs to support the survival of targeted cells.Although oxygen-releasing biomaterials,such as oxygen-generating microparticles(OMPs),have shown promise for enhancing the oxygen supply of microenvironments in injured tissues,whether this approach is scalable for large tissues and whether tissue-specific bioinks with varying OMP concentrations remain printable remain unknown.This study addresses this critical gap by introducing an innovative class of engineered oxygenated bioinks that combine colloidal-based microgels with OMPs.We report that incorporating nanosized calcium peroxide(nCaO_(2))and manganese oxide nanosheets(nMnO_(2))into hydrophobic polymeric microparticles enables precise modulation of oxygen release while controlling hydrogen peroxide release.Moreover,the fabrication of oxygenating and cytocompatible colloidal gels is achieved using an aqueous two-phase system.This study thoroughly evaluates the fundamental characteristics of the resulting bioink,including its rheological behaviors,printability,shape fidelity,mechanical properties,and oxygen release properties.Moreover,this study demonstrates the macroscopic scalability and cytocompatibility of printed constructs produced via cell-laden oxygenating colloidal bioinks.By showcasing the effectiveness of extrusion-based bioprinting,this study underscores how it can be used to fabricate biomimetic tissues,indicating its potential for new applications.The findings presented here advance the bioprinting field by achieving scalability with both high cell viability and the possibility of mimicking specifically oxygenated tissues.This work thereby offers a promising avenue for the development of functional tissues with enhanced physiological relevance.

Photostability of colloidal single photon emitter in near-infrared regime at room temperature

The photostability of a colloidal single photon emitter in near-infrared regime at room temperature is investigated.The fluorescence lifetime,blinking phenomenon,and anti-bunching effect of a single CdTeSe/ZnS quantum dot with an emission wavelength of 800 nm at room temperature are studied.The second-order correlation function at zero delay time is much smaller than 0.1,which proves that the emission from single quantum dots at 800 nm is a highly pure single-photon source.The effects of the irradiation duration on the fluorescence from single quantum dots are analyzed.The experimental results can be explained by a recombination model including a multi-nonradiative recombination center model and a multi-charged model.

Colloidal Gold Immunochromatographic Assay for Rapid On-Site Detection of Tetracycline in Seawater

Recently increasing concerns from the scientists and public have been paid for seawater pollution due to tetracycline(TC)overuse in maricultural area.However,there are few methods or instruments that can be used for specific and rapid detection of this antibiotic in seawater.In this study,the colloidal gold immunochromatographic assay(CG-ICA)was used to achieve this goal.A commercialized monoclonal antibody against TC(anti-TC mAb)was selected because of its higher sensitivity(half-maximal inhibitory concentration of 2.38μgL^(-1)).The prepared CG particles(average diameter of 20 nm)were used to label anti-TC mAb at pH 8.0.The conjugate pad was formed by spraying the CG-labeled anti-TC mAb on a glass fibre membrane followed by proper dryness.The test pad was made by immobilizing artificial antigen and anti-mouse mAb in the test line and the control line,respectively,in a nitrocellulose membrane.The test strip,assembled with sample pad,conjugate pad,test pad and absorbent pad,could be used to detect TC during seawater sample flowing through these components in turn.The results could be observed by the naked eye in 10min.The visible limit of detection(vLOD)was 20μgL^(-1) for TC in seawater.The CG-ICA test results were in good agreement with those of liquid chromatography-tandem mass spectrometry(LC-MS/MS).The assay also showed that,oxytetracycline(OTC)and chlortetracycline(CTC),as the structural analogues of TC,did not interfere with TC determination.Furthermore,the TC concentration given by test strip could not be affected by the fluctuation of temperature(10℃–30℃),pH(7–9)and salinity(0–40)of seawater.Therefore,CG-ICA is a suitable tool for rapid,on-site,and semi-quantitative detection of TC in seawater.

A Furan-Substituted Polymeric Hole-Transporting Material for Energy Level Regulation and Less Planarity in Colloidal Quantum Dot Solar Cells

For efficient colloidal quantum dot(CQD)solar cells(CQD-SCs),thiol-passivated p-type CQDs are generally used as a hole-transporting material(HTM);however,there are issues with the control of optoelectrical properties,low thiol passivation rate,and poor morphology with a power conversion efficiency(PCE)of approximately 11%.Although polymeric HTMs have been introduced to address these issues,maximizing efficiency and achieving green-solvent processability and thermal stability for commercialization is necessary.Here,we synthesize a novel benzodifuran(BDF)-based HTM(asy-ranPBTBDF)showing an electron-deficient state,low steric hindrance,and low planarity compared to those of a typical benzodithiophene(BDT)-based HTM(asy-ranPBTBDT).BDF properties lead to deep high occupied molecular orbital(HOMO)levels,closeπ-πstacking,excellent solubility,and amorphous properties related to efficiency,green-solvent processability,and thermal stability.With these benefits,the asy-ranPBTBDF-based CQD-SC showed enhanced open-circuit voltage(Voc)(0.65 V)and PCE(13.29%)compared to those of the asy-ranPBTBDT-based device(0.63 V and 12.22%)in toxic processes with chlorobenzene.The asy-ranPBTBDF-based CQD-SC showed a PCE of 12.51%in a green-solvent process with 2-methylanisole and improved thermal stability at 80℃(83.8%retaining after 24 h)owing to less lateral crystallization than the asy-ranPBTBDT-based device(60.8%retaining after 24 h).

Review of roll-to-roll fabrication techniques for colloidal quantum dot solar cells

Colloidal quantum dots(CQDs)are of great interest to photovoltaic(PV)technologies as they possess the benefits of solution-processability,size-tunability,and roll-to-roll manufacturability,as well as unique capabilities to harvest near-infrared(NIR)radiation.During the last decade,lab-scale CQD solar cells have achieved rapid improvement in the power conversion efficiency(PCE)from~1%to 18%,which will potentially exceed 20%in the next few years and approach the performance of other PV technologies,such as perovskite solar cells and organic solar cells.In the meanwhile,CQD solar cells exhibit long lifetimes either under shelf storage or continuous operation,making them highly attractive to industry.However,in order to meet the industrial requirements,mass production techniques are necessary to scale up the fabrication of those lab devices into large-area PV modules,such as roll-to-toll coating.This paper reviews the recent developments of large-area CQD solar cells with a focus on various fabrication methods and their principles.It covers the progress of typical large-area coating techniques,including spray coating,blade coating,dip coating,and slot-die coating.It also discusses next steps and new strategies to accomplish the ultimate goal of the low-cost large-area fabrication of CQD solar cells and emphasizes how artificial intelligence or machine learning could facilitate the developments of CQD solar cell research.

Three-dimensional Ordered Silica Colloidal Film Self-assembly Deposited on a VerticalSubstrate

A method for preparation of particle crystal film constructed from monodisperse silica colloidal particles in diameter of about 300 nm is reported. The films were prepared from an ethanol suspension by vertical deposition that relies on capillary forces to assemble colloidal crystal particles on a vertical substrate. The 3D ordered films were characterized by transmission spectra and scanning electric microscope (SEM). The effect of evaporation temperature, particle concentration and sintered temperature on the quality of colloidal particle crystal film was investigated.

Influence of colloidal particle transfer on the quality of self-assembling colloidal photonic crystal under confined condition

The relationship between colloidal particle transfer and the quality of colloidal photonic crystal（CPC） is investigated by comparing colloidal particle self-assembling under the vertical channel（VC） and horizontal channel（HC） conditions.Both the theoretical analyses and the experimental measurements indicate that crystal quality depends on the stability of mass transfer.For the VC,colloidal particle transfer takes place in a stable laminar flow,which is conducive to forming high-quality crystal.In contrast,it happens in an unstable turbulent flow for the HC.Crystals with cracks and an uneven surface formed under the HC condition can be seen from the images of a field emission scanning electron microscope（SEM） and a three-dimensional（3D） laser scanning microscope（LSM）,respectively.

Rheological behavior of ZnO suspension with thermosensitive poly(N-isopropylacrylamide) for colloidal processing of ceramics

Novel colloidal processing using thermosensitive poly（N-isopropylacrylamide） （PNIPAM） as a coagulating agent has beendeveloped to prepare complex-shaped ceramic components. In this work, the properties of PNIPAM aqueous solutions and therheological behavior of ZnO suspensions with PNIPAM were investigated. The results show that the PNIPAM solutions exhibitobvious thermosensitivity and its transition temperature is around 32℃. When the temperature is above 40℃ （Tc, the criticaltransition temperature of thermosensitive suspension）, the 50% ZnO （volume fraction） suspension with 8 mg/mL PNIPAM has asharp increase in viscosity and reaches up to 11.49 Pa·s at 50℃, displaying strong elasticity. The main reasons are the increase ofeffective volume fraction attributed to precipitation of PNIPAM segments and the flocculation between ZnO powder particles. Inaddition, the maximum solid loading （volume fraction） at 20 ℃ is higher than that at 40℃, which proves that the phase transition ofPNIPAM can induce the flocculation of suspension.

A Simple and Rapid Colloidal Gold-based Immunochromatogarpic Strip Test for Detection of FMDV Serotype A

A sandwich format immunochromatographic assay for detecting foot-and-mouth disease virus (FMDV) serotypes was developed. In this rapid test,affinity purified polyclonal antibodies from Guinea pigs which were immunized with sucking-mouse adapted FMD virus (A/AV88(L) strain) were conjugated to colloidal gold beads and used as the capture antibody,and affinity purified polyclonal antibodies from rabbits which were immunized with cell-culture adapted FMD virus (A/CHA/09 strain) were used as detector antibody. On the nitrocellulose membrane of the immunochromatographic strip,the capture antibody was laid on a sample pad,the detector antibody was printed at the test line(T) and goat anti-guinea pigs IgG antibodies were immobilized to the control line(C). The lower detection limit of the test for a FMDV 146S antigen is 11.7ng/ml as determined in serial tests after the strip device was assembled and the assay condition optimization. No cross reactions were found with FMDV serotype C,Swine vesicular disease (SVD),Vesicular stomatiti svirus (VSV) and vesicular exanthema of swine virus (VES) viral antigens with this rapid test. Clinically,the diagnostic sensitivity of this test for FMDV serotypes A was 88.7% which is as same as an indirect-sandwich ELISA. The specificity of this strip test was 98.2% and is comparable to the 98.7% obtained with indirect-sandwich ELISA. This rapid strip test is simple,easy and fast for clinical testing on field sites; no special instruments and skills are required,and the result can be obtained within 15 min. To our knowledge,this is the first rapid immunochromatogarpic assay for serotype A of FMDV.

Inorganic Colloidal Electrolyte for Highly Robust Zinc‑Ion Batteries

Zinc-ion batteries(ZIBs)is a promising electrical energy storage candidate due to its eco-friendliness,low cost,and intrinsic safety,but on the cathode the element dissolution and the formation of irreversible products,and on the anode the growth of dendrite as well as irreversible products hinder its practical application.Herein,we propose a new type of the inorganic highly concentrated colloidal electrolytes(HCCE)for ZIBs promoting simultaneous robust protection of both cathode/anode leading to an effective suppression of element dissolution,dendrite,and irreversible products growth.The new HCCE has high Zn^(2+)ion transference number(0.64)endowed by the limitation of SO4^(2−),the competitive ion conductivity(1.1×10^(–2) S cm^(−1))and Zn2+ion diffusion enabled by the uniform pore distribution(3.6 nm)and the limited free water.The Zn/HCCE/α-MnO2 cells exhibit high durability under both high and low current densities,which is almost 100%capacity retention at 200 mA g^(−1) after 400 cycles(290 mAh g^(−1))and 89%capacity retention under 500 mA g^(−1) after 1000 cycles(212 mAh g^(−1)).Considering material sustainability and batteries’high performances,the colloidal electrolyte may provide a feasible substitute beyond the liquid and all-solid-state electrolyte of ZIBs.

Preparation of colloidal gold immunochromatography strip for detection of methamidophos residue

Methamidophos (Met) is a broad spectrum organophosphorus insecticide and acaricide.Even a trace of its residue is harmful to humans and many animals.In this study,the synthesis and identification of colloidal gold particles and antibody-colloidal gold conjugates were performed,and the preparation of colloidal gold immunochromatography strip was conducted for detection of Met residue.The size of colloidal gold particles was checked using a transmission electron microscope (TEM).The formation of antibody-coll...

Colloidal Gas Aphrons: A Novel Approach to Preventing Formation Impairment

Colloidal gas aphrons (CGAs) were first reported by Sebba (1971) as micro bubbles (25-125 μm), composed of a gas nucleus surrounded by a thin surfactant film and created by intense stirring of a surfactant solution. Since then, these colloidal dispersions have been used for diverse applications, with a particular focus on separation processes. However, exploitation of CGAs in petroleum industry is only at the outset. CGAs were first used in west Texas in 1998, under the name Aphron drilling fluids. This kind of fluid is characterized as having a continuous phase, a high viscosity at a low shear rate and containing, as an internal phase, micro air or gas bubbles, non-coalescing and recirculating. In this paper, we illuminate the physical and chemical properties of aphron drilling fluid and its processing mechanism.

Separation of Fine Particles by Using Colloidal Gas Aphrons

This paper presents a method of separation of fine particles, of the order of a few microns or less, from aqueous media by flotation using colloidal gas aphrons (CGAs) generated in aqueous solutions. More than 150 experiments were conducted to study the effects of surfactant type, surfactant concentration, CGAs flow rate, and particle concentration on the removal efficiency (fine particles of polystyrene were used as a target compound). The results indicate that CGAs, generated from cationic surfactant of hexdecyltrimethyl ammonicum bromide (HTAB) and anionic surfactant of sodium dodecylbenzne sulfonate (SDBS), are an effective method for the separation off ine particles of polystyrene from wastewater. The flotation yields are higher than 97%.

High-gravity-assisted green synthesis of rare-earth doped calcium molybdate colloidal nanophosphors

In this work,we report an innovative route for the synthesis of rare-earth doped calcium molybdate(CaMoO4)nanophosphors by using high gravity rotating packed bed(RPB)technology and paraffin liquid as the solvent.The significant intensified mass transfer and micromixing of reactants in the RPB reactor are benefiting for homogeneous doping of rare-earth ions in the host materials,leading to nanophosphors with high quantum efficiency.The use of liquid paraffin as the solvent eliminates the safety risks associated with volatile organic compounds,increasing the potential for clean production of nanophosphors.Under excitation of deep ultraviolet(DUV)light,the CaMoO4:Na+,Eu3+nanophosphors exhibit red emission at peak wavelength of 615 nm and quantum yield of up to 35.01%.The CaMoO4:Na+,Tb3+nanophosphors exhibit green emission at peak wavelength of543 nm with quantum yield of up to 30.66%.The morphologies of the nanophosphors are tunable from nanofibers through nanorods to nanodots and the possible mechanism of controlling the formation of different nanostructures is proposed on the basis of experimental results and theoretical analysis of mesoscience.These nanophosphors are highly dispersible in organic solvents and utilized for fabricating fabrication of flexible,freestanding luminescent films based on silicone resin.We also demonstrate the red LEDs consisting of the hybrid films of CaMoO4:Na+,Eu3+nanoparticles as color-converting phosphors and DUV LEDs as illuminators,offering strong potential for future nanophosphors-basedsolid-state lighting systems.

Preparation of Non-spherical Colloidal Silica Nanoparticle and Its Application on Chemical Mechanical Polishing of Sapphire

Non-spherical colloidal silica nanoparticle was prepared by a simple new method, and its particle size distribution and shape morphology were characterized by dynamic light scattering(DLS) and the Focus Ion Beam(FIB) system. This kind of novel colloidal silica particles can be well used in chemical mechanical polishing(CMP) of sapphire wafer surface. And the polishing test proves that non-spherical colloidal silica slurry shows much higher material removal rate(MRR) with higher coefficient of friction(COF) when compared to traditional large spherical colloidal silica slurry with particle size 80 nm by DLS. Besides, sapphire wafer polished by non-spherical abrasive also has a good surface roughness of 0.460 6 nm. Therefore, non-spherical colloidal silica has shown great potential in the CMP field because of its higher MRR and better surface roughness.

Kinetic Rate Constant of Liquid Drainage from Colloidal Gas Aphrons

A kinetic model fitted by the empirical equation has been proposed to describe the liquid drainage behavior. Rate constants （kd） of liquid drainage equation could be obtained from the above empirical equation. In this paper, the stability of the colloidal gas aphrons （CGAs）, the effect of concentrations of sodium dodecyl benzene sulphate （SDBS）, dodecyl trimethylammonium bromide （HTAB） and polyoxyethylene sorbitol anhydride monolaurate（Tween-20）, temperature, stirring speed, stirring time, and various kinds of salts on the kd of liquid drainage are further investigated. The results show that the Arrhenius equation can be successfully used to describe the relation between kd arid absolute temperature （T）, and concentrations of surfactants, stirring speed, stirring time and salinities also have great effect on the kd. At last, the CGAs drainage mechanism is explained from analysis of the rate of liquid drainage as a function of time.

Fabrication of Large-area 3-D Ordered Silvercoated Colloidal Crystals and Macroporous Silver Films Using Polystyrene Templates

The highly ordered silver-coated colloidal crystals arrays and macroporous silver films were derived through an electrostatics-induced adsorption effect using polystyrene(PS) as templates. Carboxyl-modified PS microspheres were prepared by emulsifier-free emulsion polymerization using methacrylic acid(MAA) as the functional monomer. PS microspheres were self-assembled into close packing colloidal crystals of facecentered cubic arrays to the substrate with vertical deposition method. These colloidal crystals were modified using dopamine(DA) to form poly-dopamine(PDA) during its oxidative polymerization. Through electrostatic interaction, the silver nanoparticles were deposited and adsorbed onto the surfaces of colloidal crystals templates by exposing [Ag(NH_3)_2]^+solution to infrared irradiation. Removal of the polymeric template by etching with methylbenzene solvent resulted in 3D ordered macroporous silver films. The structural and properties of the ordered silver-coated arrays and macroporous silver films were characterized by field emission scanning electron microscopy(FE-SEM), X-ray diffraction(XRD), UV-vis spectroscopy and surface-enhanced Raman spectroscopy(SERS). The results indicate that the prepared silver-coated arrays and macroporous silver films possess the features of ordered multilayer arrangement, uniformity and repeatability as well as an ideal SERS effect.

Determination of the Structure of Polyacrylamide/Aluminum Citrate Colloidal Dispersion Gel System

1 INTRODUCTIONIn recent years,colloidal dispersion gel(CDG)have been attracting more and more in thefield of enhanced oil recovery on account of the cost-effectiveness and high efficiency ofblocking formation.Compared with bulk gel(BG),CDG exhibits lower polymer concentra-tion,undefined shape and selective blocking formation characteristics.The characteris-tics of CDG and BG are related to structure.In the bulk gel a continuous network of polymermolecules is formed predominant through intermolecular cross-linkages.The

Study of colloidal phosphorus variation in estuary with salinity

The variation of colloidal phosphorus with salinity in estuary was studied in this paper, which was compared with those of particle and truly dissolved phosphorus with the purpose of finding out the similarities and differences between their behaviors in the estuary. Distribution patterns of phosphorus in particle, colloidal and truly dissolved phase at different salinities and their relationships with suspended particulate matter were also studied to understand the transformation and transporta- tion of colloidal phosphorus in estuarine area. The result showed that the concentrations of total colloidal phosphorus, organic colloidal phosphorus and inorganic colloidall phosphate all descended from river-end to sea-end, illustrating their terrigenous source. Rat.ios of organic to total colloidal phosphorus decreased with salinity＇s increment, indicating that organic phosphorus was influenced by scavenging process of colloid more significantly as compared with inorganic phosphate. Both of the phosphorus variation tendencies and the proportion between organic and inorganic phosphorus in colloidal phase was similar with that in truly dissolved phase while different from that in particle phase.

Effects of unsymmetrical geometric confinements on depletion interactions in colloidal suspensions

The depletion interactions between two large-spheres immersed in a fluid of small spheres under unsymmetrical geometrical confinement are studied through the acceptance ratio method. The numerical results show that no matter whether the volume fraction is large or small, both the depletion potential and depletion force are affected by the presence of the two plates; the closer the two large spheres are to the plate, the larger the effects of the unsymmetrical confinements.