Colloidal Copper Research Articles

Utilizing the 2nd harmonic Nd: YAG laser ablation in liquid for the production of copper oxide quantum dots: Influence of laser fluence and ablation duration

One environmentally friendly technique for creating colloids of nanoparticles is pulsed laser ablation in liquid, which stands out for its ability to create nanoparticles free of contamination without the use of hazardous chemicals. In the present work, A Q-Switched Nanosecond Nd: YAG laser was utilized to precisely produce colloidal copper oxide nanoparticles (CuONPs) through the laser ablation of a copper target immersed in distilled water. The impact of the laser fluence and laser ablation time on the size, morphology, and concentration of the generated CuONPs was investigated experimentally. The UV–visible absorption spectra of CuONPs display surface plasmonic resonance peaks in the UV region, which are attributed to interband transitions. The energy band gaps of the colloidal CuONPs were determined using UV–visible spectroscopy, and they ranged between 3.45 and 3.72 eV at various ablation times and laser fluences. The TEM micrographs were used to assess the size and morphology of the CuONPs, while the concentration and elemental composition were determined using ICP and EDXA spectroscopy. The TEM images of the CuONPs indicate a spherical shape at various laser ablation times and laser fluences. The average size of the CuONPs decreased to the quantum size range. The experimental results show that increasing laser fluence from 28.6 to 51.5 × 103 J/cm2 while keeping laser ablation time fixed for 30 min resulted in a reduction in the average size of the nanoparticles from 8.5 to 4.6 nm, respectively. Moreover, increasing laser ablation time from 10 to 50 min at a constant incident laser fluence of 34.3 × 103 J/cm2 decreased the average size of the CuONPs from 6.8 to 4.3 nm, respectively. The concentration of the synthesized CuONPs increased as laser fluence and laser ablation time increased.

(Invited) Redox Chemistries for Vacancy Modulation in Copper Phosphide Nanocrystals

Copper phosphide has been proposed as an anode material for lithium-ion batteries due to the ability to accommodate the electrochemical insertion of Li ions without substantial reorganization of the P-sublattice. We present three copper-coupled redox chemistries that allow post-synthetic modulation of the delocalized hole concentrations in colloidal copper phosphide nanocrystals. Changes in the structural, optical, and compositional properties are evaluated by powder X-ray diffraction, electronic absorption spectroscopy, solid-state nuclear magnetic resonance spectroscopy and elemental analysis. The redox chemistries presented herein can be used to obtain nanocrystals with Cu/P ratios of ~2.66–2.93, a larger range than has been possible through purely synthetic tuning. Importantly, oxidation with a divalent metal halide and trioctylphosphine allows access to a uniquely Cu-deficient composition. Copper phosphide nanocrystal thin-films oxidized in this way would be ideal candidates for fundamental electrochemical lithiation studies.

Transgenerational Inheritance Effects of Copper Oxide Nanoparticles (CuONPs) Induced Asthenospermia and Infertility via Gamete H3K9me3 Insufficiency Pathway in Mice.

The widespread use of colloidal copper oxide nanoparticles (CuONPs) poses substantial health risks to humans. CuONPs can penetrate the blood-testis barrier and induce spermatocide, and the understanding of the adverse effects of asthenospermia on spermatogenesis, embryonic development, and transgenerational inheritance is limited. In this study, male mice were orally administered different doses of CuONPs via continuous exposure for one spermatozoon development period (35 days) and then exposed without CuONPs for another 35 days. The CuONPs that accumulated in the testes induced oxidative stress (OS), affected the progress of spermatogenesis and sperm capacitation, and compromised epigenetic modifications, resulting in asthenospermia and embryonic development anomalies in male offspring. In a mechanism, CuONP exposure impaired the self-renewal and differentiation of spermatogonial stem cells (SSCs) via the GDNF/PI3K/AKT signaling pathway under OS. Importantly, CuONP exposure was found to potentially lower H3K9me3 levels in paternal sperm, which would further transgenerational transmission and interfere with sperm mitochondrial energy metabolism and motility, leading to asthenospermia and subfertility in the offspring. Collectively, these data reveal a molecular mechanism by which CuONP exposure disturbs H3K9me3 levels via the OS pathway, which further mediates the asthenospermic effects of reproductive failure by interfering with mitochondrial arrangement and formation in the next generation.

Enrichment of Polycyclic Aromatic Hydrocarbon (PAH)-Degrading Strictly Anaerobic Sulfate-Reducing Cultures from Contaminated Soil and Sediment.

Sulfate-reducing bacteria (SRB) are crucial players in global biogeochemical cycling and some have been implicated in the anaerobic biodegradation of organic pollutants, including recalcitrant and hazardous polycyclic aromatic hydrocarbons (PAHs). Obtaining PAH-degrading SRB cultures for laboratories is of paramount importance in the development of the young field of anaerobic biodegradation of PAHs. SRB grow exceptionally slowly on PAH substrates and are highly sensitive to oxygen. Consequently, enrichment and maintenance of PAH-degrading SRB cultures and characterization of the biodegradation process remain a tedious and formidable task, especially for new researchers. To address these technical constraints, we have developed robust and effective protocols for obtaining and characterizing PAH-degrading SRB cultures. In this set of protocols, we describe step-by-step procedures for preparing inocula from contaminated soil or sediment, preparing anoxic medium, establishing enrichment cultures with PAHs as substrates under completely anaerobic sulfate-reducing conditions, successive culture transfers to obtain highly enriched cultures, rapid verification of the viability of SRB in slow-growing cultures, assessment of PAH degradation by extracting residuals using organic solvent and subsequent analysis by gas chromatography-mass spectrometry, and spectrophotometric determination of sulfate and sulfide in miniaturized, medium-throughput format. These protocols are expected to serve as a comprehensive manual for obtaining and characterizing PAH-degrading sulfate-reducing cultures. © 2024 The Author(s). Current Protocols published by Wiley Periodicals LLC. Basic Protocol 1: Obtaining PAH-degrading strictly anaerobic sulfate-reducing enrichment cultures from contaminated soil and sediment Support Protocol 1: Operation and maintenance of an anaerobic workstation Support Protocol 2: Setup of gas purging systems for preparing anoxic solutions Support Protocol 3: Verification of viability in slow-growing SRB enrichment cultures Support Protocol 4: Extraction of genomic DNA from low-biomass cultures Basic Protocol 2: Extraction of residual PAH from liquid culture and analysis by GC-MS Basic Protocol 3: Spectrophotometric determination of sulfate concentration in SRB cultures Basic Protocol 4: Spectrophotometric determination of sulfide concentrations in SRB cultures by the methylene blue method Alternate Protocol: Spectrophotometric determination of sulfide concentrations in SRB cultures by the colloidal copper sulfide method.

Effects of copper nanoparticles on oxidative stress genes and their enzyme activities in common carp (Cyprinus carpio)

Copper nanoparticles (Cu-NPs) are becoming increasingly prevalent in the environment due to their wide range of applications, posing potential threats to living organisms. Negative effects of Cu-NP exposure have been confirmed in many fish species, and they include disorders in the expression of oxidative stress genes and the activity of enzymes they encode. Common carp, known for its sensitivity to nanopollutants in water, serves as a valuable model organism for nanoparticle toxicity assessment. This study investigated the effects of specific Cu-NPs – copper nanopowder (Cu-NPs), colloidal copper nanoparticles (Cu), and copper oxide nanoparticles (CuO-NPs) – on gene expression and enzyme activity (GPX, CYP1A, HSP70, SOD, CAT) in C. carpio hatchlings, utilizing molecular biology tools and biochemical analyses. Results showed that Cu increased the expression of the hsp70 gene, Cu-NPs elevated the expression of the cyp1a and hsp70 genes, and CuO increased cyp1a expression. Conversely, sod and cat exhibited reduced expression across all samples (Cu, Cu-NPs, CuO). All Cu forms induced significant ROS accumulation and notable alterations in oxidative stress biomarkers (SOD, CAT, GPX).

Chirality Engineering of Colloidal Copper Oxide Nanostructures for Tailored Spin-Polarized Catalysis.

The combination of the chiral concept and inorganic nanostructures holds great potential for significantly impacting catalytic processes and products. However, the synthesis of inorganic nanomaterials with engineered chiroptical activity and identical structure and size presents a substantial challenge, impeding exploration of the relationship between chirality (optical activity) and catalytic efficiency. Here, we present a facile wet-chemical synthesis for achieving intrinsic and tunable chiroptical activity within colloidal copper oxide nanostructures. These nanostructures exhibit strong spin-polarization selectivity compared with their achiral counterparts. More importantly, the ability to engineer chiroptical activity within the same type of chiral nanostructures allows for the manipulation of spin-dependent catalysis, facilitating a study of the connection between the chiroptical magnitude (asymmetric factor) and catalytic performance in inorganic nanostructures. Specifically, using these materials as model catalysts in a proof-of-concept catalytic reaction, we reveal a linear correlation between the asymmetric factor of chiral nanomaterials and the efficiency of the catalytic reaction. This work paves the way for the development of chiral inorganic nanosystems and their application in catalysis through chiroptical engineering.

Study the Influence of Laser Energy on the Surface Morphology of Copper Nanoparticles Prepared by Pulsed Laser Extirpation Method in Liquid

A study reports a novel synthesis of pure copper and the effect of laser energy on optical properties and the particle size of colloidal copper nanoparticles prepared by pulsed laser ablation in liquid (PLAL). Different laser energies (600,700,800 mJ) of pulsed laser (Nd: YaG) were used to prepare colloidal copper nanoparticles size of about (40.4 nm - 91.3 nm) which were measured using Field Emission Scanning Electron Microscopy (FESEM). The presence of Copper NPs in distilled water, respectively, with nanostructure in the shape of a spherical construction and size of about 50 nm were measured using Transmission Electron Microscopy (TEM). The absorption spectrum and Surface Plasmon Resonance (SPR) were measured to study the optical properties of the prepared copper nucleus, and the results showed that the SPR and high optical density were found in the 320 wavelengths at the laser energy of (600 mJ), present at wavelength 333 to the laser energy (700 mJ) and shifted to a lower wavelength (blue shift) with a higher optical density, a wavelength of 341 at the laser energy of (800 mJ).

Simple and Intelligent Electrochemical Detection of Ammonia over Cuprous Oxide Thin Film Electrode

To realize simple and intelligent electrochemical ammonia (NH3) detection in water, highly dense colloidal copper nanoparticles (CuNPs) were prepared and subsequently deposited onto a glassy carbon electrode (GCE). The CuNPs/GCE was then placed in an oven at 60 °C to intelligently transform CuNPs into cuprous oxide (Cu2O) thin film. The colloidal CuNPs were characterized by ultraviolet-visible (UV-Vis) spectroscopy, whereas the fabricated Cu2O/GCE was subjected to Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), and electrochemical impedance spectroscopy (EIS). The XRD of Cu2O/GCE showed the crystalline nature of the thermally converted Cu2O thin film, whereas XPS demonstrated that the thin film formed on the surface of GCE was primarily composed of Cu2O. The SEM images of Cu2O/GCE revealed Cu2O crystals with hexapod morphology. The EIS study exhibited substantially higher charger transfer activity of Cu2O/GCE compared to bare GCE. The drop coating of ammonia (NH3) solution onto Cu2O/GCE enabled the fabricated electrode to be utilized as an electrochemical sensor for NH3 detection in water. The cyclic voltammetric (CV) behavior of NH3/Cu2O/GCE was investigated in 0.1 M pH 7 phosphate buffer, which led to the formation of a copper-ammonia complex and revealed the nobility of the fabricated electrode. The square wave voltammetric (SWV) response was linear over the 10 µM and 1000 µM ranges with a detection limit of 6.23 µM and good reproducibility. The NH3/Cu2O/GCE displayed high selectivity for the detection of NH3 in the presence of various coexisting cations and anions in 0.1 M pH 7 phosphate buffer. The recovery of NH3 in the drinking water sample varied from 98.2% to 99.1%.

Influence of ultraviolet irradiation on the optical properties and biological activity of copper nanoparticles prepared by pulsed laser ablation

In this study, we synthesized colloidal copper nanoparticles (CuNPs) utilizing Q-switched Nd:YAG laser ablation on a copper plate immersed in double-distilled water at energies of 200 and 400 mJ, respectively, with 100, 200, 300, 400, and 500 pulses. The size and optical properties of nanoparticles were determined using a UV–Vis spectrophotometer, a transmission electron microscope (TEM), and a field emission scanning electron microscope (FE-SEM). The absorption spectra exhibited two surface plasmon resonance peaks (λSPR), one at 217 nm for copper oxide nanoparticles (CuONPs) and the other at 636 nm for CuNPs, with the increase in laser pulses. Consequently, the optical bandgap increased by roughly 3 eV. The TEM and FE-SEM analyses showed nearly spherical Cu nanoparticles with average diameters of 33 and 38 nm for laser energies of 200 and 400 mJ, respectively. An analysis of x-ray diffraction patterns revealed that CuONPs contained the crystallographic planes of a monoclinic and an orthorhombic crystal system. Additionally, the mean crystallite size of laser-ablated nanoparticles increased with increasing pulse energy. Furthermore, the absorption and optical bandgap of CuNPs increased slightly with an increase in ultraviolet irradiation exposure. The results of our study showed an increased inhibitory effect against both Staphylococcus aureus bacteria and Escherichia coli bacteria when CuNPs were irradiated by ultraviolet type C.

Reflections into Ptolemaic Glass II: Characterizing Yellow, Yellowish‐orange, Red, and Brown Inlays from Tebtynis

AbstractA systematic and extensive analytical study was carried out on the loose inlays discovered in the Ptolemaic workshop of Tebtynis (Fayum oasis, Egypt). This paper presents data derived from the multi‐methodological archaeometric investigations (optical microscopy, scanning electron microscopy–energy‐dispersive spectroscopy, electron probe microanalysis, micro‐Raman spectroscopy) performed on a set of intentionally colored and opacified glasses. In particular, we will discuss the textural, chemical, and mineralogical results related to the study of the yellow, yellowish‐orange, red, and brown inlays and semi‐finished/waste products now preserved at the Museo Egizio, Torino. The results highlight the presence of natron (low‐magnesium glasses, LMG) and plant ash (high‐magnesium glasses, HMG) base glass, coexisting with intermediate composition. Yellow samples are opacified using lead antimonates doped with iron and sometimes tin; conversely, yellowish‐orange specimens and the only brown sample are characterized by nanocrystals of cuprite. Red glasses are found in two variants: Dull reds are HMG with colloidal metallic copper particles, while sealing‐wax reds show LMG composition, associated with dendritic cuprite dispersed in a transparent, greenish matrix.

Preparation and Structural Characterization of Thin Films of CuInS2 by Sintering Colloidally Synthesized Nanoparticles at Moderate Temperature

Copper indium disulfide nanoparticles continue attracting attention as absorber material in light harvesting devices. The preparation of thin films by deposition of this material from colloidal solution remains challenging. Typically, colloidal semiconductor nanoparticles are surrounded by long organic ligand molecules which are required to stabilize the particles during synthesis. A common way to obtain conductive thin films is the development of ligand exchange procedures that need to be applied prior to film deposition. However, in the case of copper indium disulfide nanoparticles, appropriate procedures are still missing. Therefore, an alternative approach is investigated herein. Colloidal copper indium disulfide nanoparticles are synthesized and deposited on substrates. Instead of applying a ligand exchange procedure, thermal removal of the ligands and sintering of the inorganic film are explored. Results on the preparation of the nanoparticle films, their structural investigation, and conductivity measurements are reported.

Effect of stagnation period and flow rate on soluble and particulate Pb leaching in copper pipe water distribution systems

Extremely high lead level in tap water caused by particulates has attracted increasing attention in recent years. Despite extensive research on the role of particulate Pb in water supply systems with lead service lines, little information is available on the role of particulate Pb in copper (Cu) water distribution systems. In this study, the dissolved, colloidal, and particulate lead and copper concentrations in representative prototype copper pipe water distribution systems with leaded solder joints and brass fixtures are measured. The effects of flow rate and stagnation time on metal fractionation are investigated. For each experimental scenario, all the water that stagnated inside the system is sampled to have a comprehensive understanding of lead contamination. Sampled at flow rates of 200–250 mL/s, the soluble lead and copper make up 60–96 % of the total concentration in the samples after hours of stagnation. More than half of the Pb and Cu particles are larger than 0.8 μm. Higher flow rates result in substantial increases in particulate metal concentrations but have no apparent effect on dissolved metals. The soluble and particulate copper concentrations (∼ 100–250 μg/L) both increase with stagnation time. For the case of Pb, while the particulate concentration increases (up to ∼ 40 μg/L after 12 h), the soluble concentration does not change significantly beyond 4 h; this can be attributed to the different solubilities of Pb (∼ 20 μg/L) and Cu (∼ 200 μg/L) in tap water. The results also show that particulates suspended by clean “once through” water (without prior stagnation) can lead to high levels of Pb contamination (> 10 μg/L).

Highly efficient and sensitive non-enzymatic glucose biosensor based on flower-shaped CuO-colloid nanoparticles decorated with graphene-modified nanocomposite electrode

In this work, copper nanoparticles were synthesized through the colloidal and solution combustion method, and their electrochemical properties were evaluated using three electrode systems to detect glucose content. The solution combustion method using the fuels glycine (Gly) and hydrazine (Hyd) produces nanoparticles with amorphous spherical forms and a small flake-like structure. The colloidal method yields Cu-Colloid nanoparticles that have a homogenous phase and a flower-like structure with high electro-oxidative current due to the large surface area of the developed nanoparticle which is in contact with the glucose. A glucose biosensor was then fabricated using the developed colloidal copper nanoparticles modified with graphene-coated on indium-coated tin oxide (ITO) glass substrate (Flower shaped-CuO/G/ITO) as a working electrode. The copper nanoparticles were characterized by an X-ray diffractometer, UV–VIS spectrometer, Transmission, and Scanning electron microscope for crystalline, morphological, surface studies with 10–20 nm in diameter, 280–310 nm absorption range, and energy bandgap of 1.45ev. The lower detection limit of 1 μmol L−1, the sensitivity of 1610 μA mM−1 cm−2, and the linear range of 1 μMto μ850 M at an applied potential of +0.60 V vs. Ag/AgCl was obtained for the developed nanocomposite electrode. The developed bioelectrode shows good stability and reproducibility with less response time making it a promising electrode for developing a non-enzymatic glucose biosensor.

Colloidal copper oxide nanoparticles leading to a biphasic dose-response in growth inhibition of Staphylococcus aureus.

Aim: The dose response in growth inhibition of Staphylococcus aureus treated with colloidal copper oxide nanoparticles (CuO-NP) was evaluated. Methods: An in vitro microbial viability assay was conducted with CuO-NP concentrations spreading over the 0.4-848.0μg/ml range. The dose-response curve was modeled with a double Hill equation. UV-Visible absorption and photoluminescence spectroscopies allowed tracking concentration-dependent modifications in CuO-NP. Results: Two specific phases separated by the critical concentration of 26.5μg/ml were observed in the dose-response curve, with each exhibiting proper IC50 parameters, Hill coefficients and relative amplitudes. Spectroscopy techniques reveal the occurrence of aconcentration-triggered aggregation of CuO-NP starting from this critical concentration. Conclusion: The findings demonstrate a dose-related change in S. aureus sensitivity to CuO-NP, which probably arises from the aggregation of this agent.

Achieving Large-Capability Adsorption of Hg0 in Wet Scrubbing by Defect-Rich Colloidal Copper Sulfides under High-SO2 Atmosphere.

This paper reports on a novel method to remove Hg0 in the wet scrubbing process using defect-rich colloidal copper sulfides for reducing mercury emissions from non-ferrous smelting flue gas. Unexpectedly, it migrated the negative effect of SO2 on mercury removal performance, while also enhancing Hg0 adsorption. Colloidal copper sulfides demonstrated the superior Hg0 adsorption rate of 306.9 μg·g-1·min-1 under 6% SO2 + 6% O2 atmosphere with a removal efficiency of 99.1%, and the highest-ever Hg0 adsorption capacity of 736.5 mg·g-1, which was 277% higher than all other reported metal sulfides. The Cu and S sites transformation results reveal that SO2 could transform the tri-coordinate S sites into S22- on copper sulfides surfaces, while O2 regenerated Cu2+ via the oxidation of Cu+. The S22- and Cu2+ sites enhanced Hg0 oxidation, and the Hg2+ could strongly bind with tri-coordinate S sites. This study provides an effective strategy to achieve large-capability adsorption of Hg0 from non-ferrous smelting flue gas.

Temperature controlled morphology transformation during aging of colloidal copper nanoparticles produced by laser ablation in water

The colloidal nanoparticles produced from bulk metal by laser ablation in water usually oxidize during aging. Such transformation could be used as a tool for nanoarchitecture if the control parameters are known. Here we studied in detail the transformation of copper-based nanoparticles in water during the colloid aging and the evolution of nanoparticle morphology at various temperatures. The spherical Cu@Cu2O core-shell nanoparticles were produced by laser ablation of Cu target in water. The aging of prepared colloid was investigated in situ by UV–visible absorption spectroscopy. The nanoparticle morphology and composition were characterized by scanning and transmitting electron microscopies, X-ray photoelectron and Raman spectroscopies. The aging of colloidal nanoparticles resulted in morphology changes and composition transformation to CuO. The nanoparticle sizes enlarged due to Ostwald ripening and aggregative growth either isotropically at room temperature (25 ℃) or by forming elongated nano-spindles at temperature above 35 ℃. The occurred transformation was characterized by Kolmogorov-Johnson-Mehl-Avrami approach which allowed to extract the activation energy of the process. The obtained results are useful for both nanoarchitecture and gaining colloid stability.

NIR laser-conjugated glutathione-coated Mn-doped CuS nanoprisms as photothermal agent for cancer treatment.

The cancer treatment by laser-conjugated nanomaterial has become a new developing trend due of their unique physicochemical performance. The previous few studies reported the preparation of undoped CuS nanoprisms. The current research was concerned with the Mn doping effect on the CuS nanoprisms and its activity in tumor toxicity of M.D. Anderson-Metastatic Breast 231 (MDA-MB-231) cell line with laser treatment. To prepare a novel CuS and Mn-doped CuS nanoprisms with high surface area by two-phase colloidal method, copper nitrate and sulfur powder were used as sources of copper and sulfur respectively. The prepared nanoprisms were investigated as antibacterial and photothermal agents in MDA-MB-231 cancer treatment using near-infrared (NIR) laser. The Mn-CuS nanoprisms were modified with glutathione (GSH) to decrease the cytotoxicity and increase the biocompatibility. The characterization of synthesized nanoprisms involved the structural, compositional, surface charges, optical, and morphological property analyses. X-ray diffraction (XRD) showed the peaks of hexagonal covellite copper sulfide nanoparticles and additional diffraction peaks at Mn-CuS which are assigned to orthorhombic chalcocite CuS. The transmission electron microscopy (TEM) images showed that the CuS and Mn-CuS nanoparticles have nanoprism morphology. The antibacterial activity test revealed that the activity enhances by doping and the prepared Mn-CuS nanostructures were more effective against the Staphylococcus aureus and Escherichia coli bacteria. The results of photothermal treatment indicated that the cancer cells were effectively killed and the GSH@Mn-CuS nanoprisms are able to be used as an efficient theranostic agent for tumor photothermal therapy in the future.

Study of Optical and Structural Properties of Copper Metal Cu Nanoparticles

Colloidal copper nanoparticles were prepared by pulsed (Nd:YAG,Q-switch) laser ablation in distilled water with a wavelength (1064nm) and frequency (1Hz) and the duration of the pulse was (10ns). Its purity is (99.9) immersed in distilled (deionized) water, where the metal target was first removed from copper placed in (5mL) of distilled water with a specific laser energy (260mJ) and for a number of fixed laser pulses (50, 100, 150) respectively. The size and optical properties of nanoparticles were characterized by transmission electron microscopy (TEM) and visible-UV spectrometry, respectively. eV) at the pulse (50) and (2.77eV) at the (100) and its value was (2.69eV) at the (150) pulse. The reason for the increase is due to the amount of material removal being greater. The results of the transmission electron microscope showed colloidal nanoparticles somewhat spherical and carnivorous, as depend on the size of the noble nanoparticles have gained wide popularity with many applications and fields, and the reason for this is due to the need for precise miniaturization of electronic devices and because of their unique character that differs from those in the usual case. Metal colloids are one of the important nano-sized materials.

Synthesis of Colloidal Copper (Cu) Nanoparticles by Pulse Laser Ablation Method (Nd:YAG 1064 nm) in Deionized Water

Copper nanoparticles are usually used for various fields, such as medical, energy, environmental, and others. Copper nanoparticles were successfully synthesized in deionized water (DIW) using the 1064 nm ND:YAG pulse laser ablation method at 85 mJ energy. The resulting colloidal nanoparticles are greenish in color. This study investigates the use of DIW liquid medium that can survive one day after being synthesized or changed. The result is that there is a change in the colloidal photo of copper (Cu) nanoparticles shortly after being synthesized and one day after being synthesized. There is a change in color to become clearer after the colloid is left alone for one day. Not only did the colloid photo change, but the absorbance of the UV-Vis testing of the Cu nanoparticle colloid also changed. Changes in UV-Vis absorption in colloids immediately after being synthesized and after colloids were left standing for one day decreased from 1.175 to 0.561, and experienced a shift in wavelength from 222.96 nm to 223.07 nm. The morphology of Cu nanoparticles was seen using FESEM with a spherical shape. The average size distribution of Cu nanoparticles is about 56.7 nm.

Assessing the colloidal stability of copper doped ZIF-8 in water and serum

Colloidal formulations to treat cardiovascular conditions are urgently needed since diseases like atherosclerosis are a major societal burden and agonizing for affected individuals. Copper ions and zinc ions as well as correctly dosed nitric oxide (NO) have long been known to alleviate these pathologies. Herein, we present strategies for size-controlled crystallization of copper-doped Zeolitic Imidazolate Framework 8 (ZIF-8). The colloidal stability and structural integrity of copper-doped ZIF-8 was assessed in water and blood serum. Key findings of the present study include that structural integrity of colloidal copper doped ZIF-8 in blood serum is maintained over several days, while disintegration occurs more quickly in water. Further, we confirmed the known ability of copper-doped ZIF-8 micro-particles to convert blood borne s-nitrosothiols into nitric oxide for the presented colloidal formulations. Nitric Oxide conversion was more moderate and sustained in colloidal copper-doped ZIF-8 formulations compared to free copper ions in solution, which is crucial for many biomedical applications. Another key finding of the present study is that the onset of rapid structural disintegration of copper-doped ZIF-8 occurs at pH 5.5, which is a common physiological pH regime of atherosclerotic plaques. Colloidal particles are known to accumulate in atherosclerotic plaques and the presented system may be a valuable addition to the emerging field of nanomedicines for atherosclerosis treatment. The present study has evaluated the colloidal stability and structural integrity, establishing required material characteristics needed for biological evaluation of the material in future dedicated studies.