Calcium Carbonate Nanoparticles Research Articles

3D-imprinted superhydrophobic polyvinylidene fluoride membrane contactor incorporated with CaCO3 nanoparticles for carbon capture

Carbon capture using membrane gas absorption was limited by membrane wetting. In this work, superhydrophobic poly(vinylidene fluoride) (PVDF) membrane contactors were developed through 3D-imprinting and nanoparticle incorporation. Membranes were cast on woven support before phase inversion in a water bath to imprint the micro-roughness. The low-cost and biocompatible calcium carbonate (CaCO3) nanoparticles were blended into PVDF dope solution to build the hierarchical structure. The nanoparticles were premodified using stearic acid to reduce surface energy or removed using ethylenediaminetetraacetic acid for achieving nanotemplating. The presence of CaCO3 nanoparticles could be observed using scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). The membrane hydrophobicity, pore size, and porosity were significantly improved due to the addition of CaCO3 and stearic acid-modified CaCO3 (SA-CaCO3). Removing CaCO3 nanoparticles enlarged the pore size greatly but affected the surface hydrophobicity slightly. The PVDF membrane incorporated with SA-CaCO3 achieved a CO2 permeation flux as high as 1.86 ± 0.05 × 10−2 mol m−2 s−1 and only showed slight changes in surface hydrophobicity after being immersed in amine solution for 50 h.

Synthesis and Characterization of BaSO4-CaCO3-Alginate Nanocomposite Materials as Contrast Agents for Fine Vascular Imaging.

Microcomputed tomography is an important technique for distinguishing the vascular network from tissues with similar X-ray attenuation. Here, we describe a composite of barium sulfate (BaSO4) nanoparticles, calcium carbonate (CaCO3) nanoparticles, and alginate that provides improved performance over microscale BaSO4 particles, which are currently used clinically as X-ray contrast agents. BaSO4 and CaCO3 nanoparticles were synthesized using a polyol method with tetraethylene glycol as solvent and capping agent. The nanoparticles show good colloidal stability in aqueous solutions. A deliverable nanocomposite gel contrast agent was produced by encapsulation of the BaSO4 and CaCO3 nanoparticles in an alginate gel matrix. The gelation time was controlled by addition of d-(+)-gluconic acid δ-lactone, which controls the rate of dissolution of the CaCO3 nanoparticles that produce Ca2+ which cross-links the gel. Rapid cross-linking of the gel by Ba2+ was minimized by producing BaSO4 nanoparticles with an excess of surface sulfate. The resulting BaSO4-CaCO3 nanoparticle alginate gel mechanical properties were characterized, including the gel storage modulus, peak stress and elastic modulus, and radiodensity. The resulting nanocomposite has good viscosity control and good final gel stiffness. The nanocomposite has gelation times between 30 and 35 min, adequate for full body perfusion. This is the first nanoscale composite of a radiopaque metal salt to be developed in combination with an alginate hydrogel and designed for medical perfusion and vascular imaging applications.

Effect of High Temperature on Compressive Strength and Microstructure of Cement Paste Modified by Micro- and Nano-calcium Carbonate Particles

Effect of High Temperature on Compressive Strength and Microstructure of Cement Paste Modified by Micro- and Nano-calcium Carbonate Particles

Comparing the effects of in-situ nano-calcite development and ex-situ nano-calcite addition on cement hydration

A comparison between the effects of in-situ formation and ex-situ addition of calcium carbonate nanoparticles (NPs) on cement hydration is herein investigated. The in-situ formation was achieved by CO2 injection during mixing (doses of 0.1%, 0.3%, 0.5%, and 0.7% by weight of cement), while NPs of precipitated CaCO3 (0.1%, 0.5%, 1%, and 5% by weight of cement) were incorporated for ex-situ addition. The hydration kinetics were investigated through isothermal calorimetry, the hydrates were quantified using thermogravimetric analysis (TGA), and the microstructure was examined with scanning electron microscopy (SEM). Both the systems (in-situ and ex-situ) accelerated hydration and increased heat of hydration compared to a reference system without calcium carbonate additions. Increasing the dosage of ex-situ NPs lead to greater acceleration and energy release, while the effects of increasing CO2 dosage were negligible. However, increasing CO2 dosage resulted in increasing amounts of carbonate formation through CO2 mineralization. Unlike those of the control system, micrographs of the CO2-activated system showed evidence of C-S-H precipitation as early as within 40 s of the start of hydration. The experimental evidence is used to develop mechanistic insights into the two modes of NP incorporation in cementitious systems.

In vitro characterization and cellular uptake profiles of TAMs-targeted lipid calcium carbonate nanoparticles for cancer immunotherapy

Tumor-associated macrophages (TAMs) are key contributors to tumor development, accelerated tumor invasion and metastasis, and induction of immunosuppression. Targeted delivery of immunomodulatory agents to promote polarization of TAMs may alleviate the immunosuppressive tumor microenvironment. Calcium carbonate nanoparticles (CCN), which exhibit excellent biocompatibility, pH sensitivity, and easy surface modification, have attracted substantial attention in targeted nano delivery. In this study, CCN were used as a matrix material to develop UNO-peptide-modified lipid CCN for targeted immunomodulation of TAMs by using the mannose receptor overexpressed on the surfaces of TAMs as targets. The preparation of CCN was optimized through single-factor testing with the gas diffusion method with the particle size as the index. The surface modification of CCN with UNO-peptide-modified phospholipids was performed, and its targeting effect on TAMs was investigated. The average particle size of the CCN and UNO-peptide-modified CCN was 144.5 ± 3.8 nm and 167.0 ± 1.3 nm, respectively. UNO-peptide-modified CCN entered TAMs via actively targeted uptake mediated by mannose receptors. Our results demonstrated that the developed UNO-peptide-modified CCN with controlled nano-size and excellent TAMs-targeting properties is a highly promising nanocarrier for targeted delivery of TAM immunomodulatory agents.

Formation of calcium carbonate nanoparticles through the assembling effect of glucose and the influence on the properties of PDMS.

In order to prepare calcium carbonate nanoparticles in a green and environmentally friendly way, the concept of bio-mineralization has been proposed. Glucose, as a common small molecular organic substance found in organisms, participates in the mineralization process in cells. By adding glucose as a chemical additive, long chains of calcium carbonate form at the initial stage and then break granularly via over-carbonation. The average size of the calcium carbonate nanoparticles is about 40 nm based on the statistical analyses of three hundred particles. The growth mechanism of calcium carbonate under the influence of glucose is obtained. After the calcium carbonate nanoparticles are modified by sodium stearate, they are introduced to the PDMS matrix to achieve the composite material. Compared with pure PDMS, the composite with additional 3% calcium carbonate has its elongation at break and tensile strength increased by 23.96% and 48.15%, respectively.

Synthesis of nanostructured protein-mineral-microcapsules by sonication.

We propose a simple and eco-friendly method for the formation of composite protein-mineral-microcapsules induced by ultrasound treatment. Protein- and nanoparticle-stabilized oil-in-water (O/W) emulsions loaded with different oils are prepared using high-intensity ultrasound. The formation of thin composite mineral proteinaceous shells is realized with various types of nanoparticles, which are pre-modified with Bovine Serum Albumin (BSA) and subsequently characterized by EDX, TGA, zeta potential measurements and Raman spectroscopy. Cryo-SEM and EDX mapping visualizations show the homogeneous distribution of the densely packed nanoparticles in the capsule shell. In contrast to the results reported in our previous paper,1 the shell of those nanostructured composite microcapsules is not cross-linked by the intermolecular disulfide bonds between BSA molecules. Instead, a Pickering-Emulsion formation takes place because of the amphiphilicity-driven spontaneous attachment of the BSA-modified nanoparticles at the oil/water interface. Using colloidal particles for the formation of the shell of the microcapsules, in our case silica, hydroxyapatite and calcium carbonate nanoparticles, is promising for the creation of new functional materials. The nanoparticulate building blocks of the composite shell with different chemical, physical or morphological properties can contribute to additional, sometimes even multiple, features of the resulting capsules. Microcapsules with shells of densely packed nanoparticles could find interesting applications in pharmaceutical science, cosmetics or in food technology.

A new study of dynamic mechanical analysis and the microstructure of polyurethane foams filled.

Polyurethane foams have good shock-absorbing properties. This article discusses the study of the physical, dynamic analysis, and microstructure of filled polyurethane foams (PUR). We used mineral fillings nanoparticles of titanium dioxide (TiO2) and calcium carbonate (C1) to support and strengthen the foam cell structure to develop shock absorption and thermal resistance properties. Dynamic mechanical analysis (DMA) and compression tests compared the mechanic characterization results with different modelling approaches. For studies of physicochemical properties, we used differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). We deduced the flame retardancy mechanism. It appears that a detailed description of the characteristics of viscosity and yield stress must take into consideration the filler's size in comparison to the cell wall's size. The effect of size distribution on the foam's microstructure was given by scanning electron microscopy (SEM). Half-open spherical cells were shown to be reduced in size with filling. The filler diffusion in polyurethane foams was used to model the composite foam. We observed that crystalline filler particles were uniformly distributed in the matrix, indicating that the total size is related to the density and is a crucial metric for the level of reinforcement.

Calcium carbonate nanoparticles of quail’s egg shells: Synthesis and characterizations

Abstract Avian eggshell is a natural biomaterial that has been used as an alternative natural source of CaCO3 and is accessible in big amounts from egg manufacturing. This study was planned to estimate CaCO3 in quail’s eggshell because it has a probable use in the progress of a novel choice of many applications. Physical properties: mineralogical documentation of the natural eggshell nanoparticles were approved using XRD and FTIR to explore the chemical bond or molecular structure of the materials. Micrographs were obtained using FESEM/EDX and TEM to identify the morphology and size of nanoparticles. The results showed that quail eggshell was soft, with white to light sand color, and a smooth texture which allows good deposition of different color spots, from black to brown spots. The resulted of eggshells signifies almost 8.4% w/w of the overall weight (12.2) gram of quail egg and 91.60% w/w of the micropowder to the full weight of (0.94) gram of quail eggshell. The results presented that calcium is the main element in an eggshell; frequently occurs in a formula of CaCO3 and the crystal construction was almost pure calcite. FTIR spectra for quail eggshell demonstrated the existence of the out of plane bending, the asymmetric stretching, and the plane bending styles of the carbonate groups, specific of normal dolomite, situated at 873 cm–1, 1405 cm–1, and 710 cm–1, respectively. The FESEM and TEM for nanoparticles were shown calcite CaCO3 nanoparticles with an ordinary size of ≤ 100 nm for FESEM and with a variety size of ≤ 50 nm for TEM. Unfortunately, eggshell is an egg product manufacturing deposit. These incomes will let fast developments in proportional studies of the organic elements of avian eggshell and their purposeful consequences by usages of eggshell in nourishment and medicine which can be applied for many resolutions that diminish their consequence on environmental contamination.

Eco-friendly processes for the synthesis of amorphous calcium carbonate nanoparticles in ethanol and their stabilisation in aqueous media

New understandings in the amorphous calcium carbonate nanoparticle synthesis lead to a final mass concentration increase by a factor of 3.5. The stabilisation in aqueous media is achieved by a 2-minute scalable process using bio-sourced stabilisers.

Triggered and monitored drug release from bifunctional hybrid nanocomposites

Polymer-coated carbon dot-containing calcium carbonate nanoparticles are reported as unique nanocomposites capable of encapsulating a chemotherapeutic drug and displaying afterglow behaviour.

Porous cellulose beads intercalated with calcium carbonate nanoparticles for dye adsorption

Porous cellulose beads intercalated with calcium carbonate nanoparticles for dye adsorption

Enhanced morphology and hydrophilicity of PVDF flat membrane with modified CaCO3@SMA additive via thermally induced phase separation method

Modified CaCO3@SMA nanoparticles obtained by coordination reaction between poly(styrene-co-maleic anhydride) (SMA) and calcium carbonate (CaCO3) nanoparticles were adopted as additive to prepare polyvinylidene fluoride (PVDF) flat membrane via thermally induced phase separation (TIPS) method with dioctyl phthalate (DOP) and dibutyl phthalate (DBP) as mixed diluent. The CaCO3 nanoparticles modified by SMA effectively reduced the adverse agglomeration of nanoparticles and made the additive disperse evenly in PVDF matrix. The presence of modified CaCO3@SMA changed the membrane morphology from dispersed spherulites with large pores to fuzzy dendrite structures with uniform pore sizes. The membrane pore sizes, pore size distribution and tensile strength were significantly improved compared to both virgin membranes and those containing unmodified CaCO3 nanoparticles. After the CaCO3 was pickled, the porosity and the connectivity between membrane pores were greatly enhanced, resulting in a significant increase in pure water flux. At the same time, the amphiphilic SMA fixed in and on the membrane surface improved the hydrophilic and anti-fouling properties demonstrated in a three-cycle test. The present study provided a potential TIPS method for the fabrication of PVDF membrane combined with a simple strategy of modified inorganic particle additive.

Ternary switchable phase transition of CaCO3 by shock waves

In the present article, we disclose shock wave induced crystallographic switchable phase transition of calcium carbonate nano particles (CaCO3 NPs). The observed profiles of powder X-ray diffraction reveal that CaCO3 NPs undergoes phase transitions in the sequential order from Calcite-I to Calcite-II and Calcite-II to Calcite-III at 50 and 100 shocks, respectively. Interestingly, reversible phase transitions have been observed from Calcite-III to Calcite-II and Calcite-II to Calcite-I at 150 and 200 shocked conditions, respectively. Rotational order-disorder of oxy-anions (CO3) and displacement of cation (Ca) take place because of the impact of shock waves thereby the observed ternary switchable phase transition results paving the way for the design of new multifunctional materials.

Dopamine- and citrate-mediated, rapid synthesis of hollow calcium carbonate nanoparticles: Their formation, metastability and transformation

Exquisite design of calcium carbonate (CaCO3) is essential to meet the demands on the properties of functional materials for various applications, where additives play a crucial role in controlling over size, orientation, polymorph, and hierarchical structure. However, we are far from achieving the elaborate control over their structures and morphologies by use of the individual additive. Herein, we develop a simple and template-free approach for the rapid fabrication of hollow CaCO3-based nanocarriers via dual-additive mediated crystallization. The roles of additives and the impact of corresponding concentrations are systematically investigated to achieve a tunable and reliable design of CaCO3 particles, simultaneously yielding clues of how the additives mediated the formation of different morphology of amorphous calcium carbonate (ACC). Compared to single citrate-mediated ACC, dual-additive mediated hollow ACC renders them the prolonged stability and also facilitates their oriented crystallization into the homogeneous hierarchical architectures. Therefore, our findings indicate that the combined additives of dopamine and citrate exert synergistic effects on hollow structure formation and metastability as well as the subsequent crystallization, which contributes to deeper insight into additive-mediated crystallization pathway. These findings may offer new opportunities to design CaCO3-based materials with controllable morphology and crystal polymorphs.

Coordination Polymer-Coated CaCO3 Reinforces Radiotherapy by Reprogramming the Immunosuppressive Metabolic Microenvironment.

Radiotherapy is widely exploited for the treatment of a large range of cancers in clinic, but its therapeutic effectiveness is seriously crippled by the tumor immunosuppression, mainly driven by the altered metabolism of cancer cells. Here, a pH-responsive nanomedicine is prepared by coating calcium carbonate (CaCO3 ) nanoparticles with 4-phenylimidazole (4PI), an inhibitor against indoleamine 2,3-dioxygenase 1 (IDO-1), together with zinc ions via the coordination reaction, aiming at reinforcing the treatment outcome of radiotherapy. The obtained pH-responsive nanomedicine, coined as acidity-IDO1-modulation nanoparticles (AIM NPs), is able to instantly neutralize protons, and release 4PI to suppress the IDO1-mediated production of kynurenine (Kyn) upon tumor accumulation. As a result, treatment with AIM NPs can remarkably enhance the therapeutic efficacy of radiotherapy against both murine CT26 and 4T1 tumors by eliciting potent antitumor immunity. Furthermore, it is shown that such combination treatment can effectively suppress the growth of untreated distant tumors via the abscopal effect, and result in immune memory responses to reject rechallenged tumors. This work highlights a novel strategy of simultaneous tumor acidity neutralization and IDO1 inhibition to potentiate radiotherapy, with great promises to suppress tumor metastasis and recurrence by eliciting robust antitumor immunity.

Nanoscale Functional Additives Application in the Low Temperature Greases.

Due to the fact that the application of AW and EP additives in low-temperature greases may lead to worse high-temperature and anti-corrosion characteristics as well as additional burden on the environment due to the content of aggressive components, in this paper, the possibility of replacing these additives with NFA, which do not have these disadvantages, was investigated. The analysis of nanosized particles being used as functional additives in greases was carried out. The morphology of the following nanoparticles was studied: montmorillonite K 10, silica, calcium car-bonate and borate, halloysite, and molybdenum disulfide incorporated in halloysite tubes. The effect of nanostructured components on the physicochemical characteristics and anti-wear and anti-scuffing properties of complex lithium, polyurea, and polymer greases were studied. Maximal improvement of anti-wear and anti-scuffing characteristics of cLi-greases was reached when using silica and calcium borate. Maximal improvement of anti-scuffing properties of PU-lubricant was reached when using calcium carbonate and the two-component NFA based on halloysite, for anti-wear properties when adding silicon dioxide and halloysite. When the concentrations of silicon dioxide and calcium carbonate was increased from 1 to 3 wt.%, there was a decrease in yield stress of the structural frame of the PU-lubricant and its colloidal stability was worse. The increase of the concentration of calcium carbonate and borate nanoparticles in the studied range led to a significant improvement of the anti-wear and anti-scuffing characteristics of the PU grease, respectively. The greases properties’ dependence from the nanostructured functional additives’ introduction method and their concentration were investigated. Nanoparticles were added into the test lubricants before and after the thermo-mechanical dispersion stage. The addition of silicon dioxide and calcium carbonate NFA after the heat treatment stage led to worsening of the characteristics of the plastic material, and the increase of their concentration from 1 to 3 wt.% formed a harder structure of Li-grease. On the contrary, the addition of calcium borate NFA is recommended after the thermomechanical dispersion. The choice of nanoparticles and the method of their addition to the lubricants of various types was carried out according to the results of the previous stage of the research. Along with the analysis of the physicochemical characteristics and anti-wear and anti-scuffing properties of the lubricants, the structure of the dispersion phase of nanomodified lubricants were studied.

Enhancement of thermal conductivity of water based individual and hybrid SiO2/Ag nanofluids with the usage of calcium carbonate nano particles as stabilizing agent

Herein, we report the enhancement in thermal conductivity and stability of aqueous nanofluid by suspending SiO2 and Ag nanoparticles in their pristine and mixed form in 5 different volumetric percentages. Ag nanoparticle used in this study was prepared using co-precipitation method in which hydrazine hydrate acted as a reducing agent. Ag nanoparticles of size 15 nm was confirmed from FESEM studies and their structural features were obtained from XRD analysis. CaCO3 nanoparticles was used as a stabilizer instead of organic stabilizers were obtained by hydro thermal method having a size of 25 nm. Nanofluids prepared by mixing these two nanoparticles in varying volumetric percentages with CaCO3 nanoparticles as a ternary nanofluid display higher stability and thermal conductivity. Zeta potential measurements of the nanofluids prepared using mixed nanoparticles exhibit higher stability than that the nanofluid prepared by suspending pristine nanoparticles in aqueous phase. Among the various combinations of nanofluids, SiO2 nanofluids stabilized using CaCO3 in 0.02 volumetric percentage revealed least zeta potential value (−36.1 mV) with a maximum thermal conductivity (0.795 W/m K) which is 31.84 % higher than the base fluid. While using this type of nanofluid in heat exchanger applications, it is expected that, it definitely alleviate sedimentation, blockage in pipelines, etc. normally produced by nanofluids.

Bubble-Liquid Membrane Method for Preparing Spherical Calcium Carbonate Nanoparticles.

In this work, we describe the principle and operation of a bubble-liquid membrane reactor, and use of the reactor to prepare spherical calcium carbonate nanoparticles. The products were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, and laser particle size analysis. The effects of additives to control crystal morphology, coating agents, and the stirring speed of the bubble-liquid membrane reactor were investigated. Spherical calcium carbonate nanoparticles with uniform dispersion and no agglomeration were obtained when a disodium hydrogen phosphate/ethylenediaminetetraacetic acid disodium salt mixture (1:1 mass ratio) was used as the additive, oleic acid was used as the coating agent (1.5 wt%), and the stirring speed was 5000-6000 r/min. The results indicate that the bubble-liquid membrane reactor may be suitable for continuous industrial production of calcium carbonate nanoparticles.

LC-MS/MS Proteomic Study of MCF-7 Cell Treated with Dox and Dox-Loaded Calcium Carbonate Nanoparticles Revealed Changes in Proteins Related to Glycolysis, Actin Signalling, and Energy Metabolism.

Simple SummaryThis work revealed that DOX-Ar-CC-NPs have the ability to promote cell death in MCF-7 cells, showing high potency in drug delivery. DOX-Ar-CC-NPs prompts cell death of MCF-7 cancer cells in vivo. LC-MS/MS Proteomic experemnt showed alteration on the expression of proteins linked to actine signaling, carbohydrate metabolisim.One of the most prevalent death causes among women worldwide is breast cancer. This study aimed to characterise and differentiate the proteomics profiles of breast cancer cell lines treated with Doxorubicin (DOX) and Doxorubicin-CaCO3-nanoparticles (DOX-Ar-CC-NPs). This study determines the therapeutic potential of doxorubicin-loaded aragonite CaCO3 nanoparticles using a Liquid Chromatography/Mass Spectrometry analysis. In total, 334 proteins were expressed in DOX-Ar-CC-NPs treated cells, while DOX treatment expressed only 54 proteins. Out of the 334 proteins expressed in DOX-CC-NPs treated cells, only 36 proteins showed changes in abundance, while in DOX treated cells, only 7 out of 54 proteins were differentially expressed. Most of the 30 identified proteins that are differentially expressed in DOX-CC-NPs treated cells are key enzymes that have an important role in the metabolism of carbohydrates as well as energy, including: pyruvate kinase, ATP synthase, enolase, glyceraldehyde-3-phosphate dehydrogenase, mitochondrial ADP/ATP carrier, and trypsin. Other identified proteins are structural proteins which included; Keratin, α- and β-tubulin, actin, and actinin. Additionally, one of the heat shock proteins was identified, which is Hsp90; other proteins include Annexins and Human epididymis protein 4. While the proteins identified in DOX-treated cells were tubulin alpha-1B chain and a beta chain, actin cytoplasmic 1, annexin A2, IF rod domain-containing protein, and 78 kDa glucose-regulated protein. Bioinformatics analysis revealed the predicted canonical pathways linking the signalling of the actin cytoskeleton, ILK, VEGF, BAG2, integrin and paxillin, as well as glycolysis. This research indicates that proteomic analysis is an effective technique for proteins expression associated with chemotherapy drugs on cancer tumours; this method provides the opportunity to identify treatment targets for MCF-7 cancer cells, and a liquid chromatography-mass spectrometry (LC-MS/MS) system allowed the detection of a larger number of proteins than 2-DE gel analysis, as well as proteins with maximum pIs and high molecular weight.