Silver Colloidal Solution Research Articles

Synthesis, morphology and Raman spectroscopy of ZnS/Ag2S heteronanostructures

Sulfide (ZnS)(Ag2S)x heteronanostructures of various composition were obtained by co-deposition from water colloidal solutions of silver and zinc nitrates using sodium sulfide as a sulfidizer and sodium citrate as a stabilizer. The formation of (ZnS)(Ag2S)x heteronanostructures was confirmed using the XRD, HAADF-STEM, SEM, EDX and Raman spectroscopy. The size of ZnS and Ag2S nanoparticles in heteronanostructures (ZnS)(Ag2S)x with x ≤ 0.01 is 2–4 and no more than 3 nm, respectively. Raman spectroscopy showed that addition of silver sulfide nanoparticles into (ZnS)(Ag2S)x heteronanostructures leads to Ag2S deposition onto the surface of ZnS nanoparticles. Doping ZnS with only 1 mol.% of colloidal Ag2S nanoparticles is sufficient to produce a silver sulfide shell on the surface of ZnS nanoparticles.

Synthesis and characterization of silver nanoparticles by electrochemical method

In this work, silver nanoparticles (Ag-NP) were synthesized by electrochemical method, using a metallic silver cathode and anode in deionized water. The polarity was inverted every 60 seconds generating a voltage variation in order to obtain three different concentrations of Ag nanoparticles: 16 ppm, 24 ppm and 34 ppm. The synthesized nanoparticles were structurally, optically and morphologically characterized by XRD, UV-Vis and Transmission Electron Microscopy (TEM), respectively. XRD patterns showed the peaks at 38.11° and 64.42° from Ag. The surface plasmon resonance peak in absorption spectra on silver colloidal solution showed absorption from 422 nm to 429 nm. TEM measurement provided an average particle size for the concentrations of 16 ppm, 24 ppm and 34 ppm of 4.23 nm, 3.95 nm and 3.27 nm, respectively. The test with the E. coli bacteria showed that there is an inhibition in the growth of the bacteria with the presence of silver nanoparticles.

The Effects of Colloidal Silver Solution and Hypochlorous Acid on Wound Healing in the New Zealand Rabbit

The aim of this study was to investigate and evaluate the effects of colloidal silver and hypochlorous acid solutions on wound healing. To evaluate the wound healing activity of colloidal silver solution and hypochlorous acid solutions, an in vivo excisional wound model was applied in New Zealand rabbits (n = 21). The rabbits were randomly divided into 3 groups with seven individuals in each group. Group 1 was used as a negative control and no treatment was applied. Groups 2 and 3 were treated with crystalline (hypochlorous acid) and colloidal silver, respectively. The treatments were applied topically (in the form of spray) to the wound area of each rabbit daily. Wound diameters were measured on days 4, 8 and 12 using calipers and histopathological examinations were performed on days 4, 8 and 12 of the treatment. In terms of wound closure, both hypochlorous acid and colloidal silver solutions showed comparable wound healing activity with the control group. In conclusion, hypochlorous acid and colloidal silver have a positive effect on dermal wound healing in rabbits.

Effect of Storage Conditions on the Stability of Colloidal Silver Solutions Prepared by Biological and Chemical Methods

The research aimed to observe the influence of the storage conditions of silver colloidal solutions prepared by biological (green) and chemical methods on their long-term stability. Green methods for reducing and stabilizing silver nanoparticles (AgNPs) use natural substances. The rosemary leaf extract was used for AgNPs synthesis, and prepared nanoparticles were spherical (average size of 12 nm). In the chemical method, commercial chemicals (NaBH4, TSC, PVP, and H2O2) were used, and two colloids were prepared; the first contained spherical nanoparticles with an average size of 8 nm, and the second triangular prisms with an average size of 35 nm. The prepared colloids were stored under four conditions: at room temperature in the light and the dark, and at a temperature of 5 °C (refrigerator) in the light and the dark. The results confirmed the influence of storage conditions on the stability of nanoparticles. Colloids stored at 5 °C in the dark show the best stability. However, differences in stability dependent on the shape of nanoparticles prepared by chemical method were also observed; triangular nanoparticles showed the least stability. Methods such as UV–vis spectrophotometry, TEM, and EDX were used to analyze the nanoparticles before and after storage.

Ocular Argyrosis Secondary to Long-term Ingestion of Self-Concocted Silver Colloidal Solution

Colloidal silver has traditionally been promoted as a cure-all for various ailments and has recently made a comeback as alternative medicine in the protection against and treatment of conditions including COVID-19. Long-term ingestion of colloidal silver can result in the buildup of silver in bodily tissues over months and years and lead to ocular argyrosis and other pathological changes. We describe a case of a 75-year-old Caucasian man who presented with a history of chronic ingestion of his own concoction of colloidal silver. Ocular examination revealed the initial presence of bilateral early drusenoid changes within the macula, confirmed with optical coherence tomography. This report seeks to bring more awareness to the clinical manifestations and current research of this rare condition.

Применение комплекса биологически активных веществ из Аronia melanocarpa в парафармацевтических фитоплёнках

The article presents the results of using non-pharmacopoeial plant raw material – dried leaves of the perennial cultivated chokeberry shrub Aronia melanocarpa (Michx.) Elliott. as a source of substances with anti-inflammatory and wound-healing effect. The development of a parapharmaceutical phytofilm based on a complex of biologically active substances from A. melanocarpa is described. The results of preclinical evaluation of the developed phytofilm in an experimental model of skin wound on outbred white rats are presented. The developed phytofilm is environmentally safe compared to synthetic analogues which production is accompanied by a negative environmental impact. Substances with antioxidant properties which can play the role of a medicinal base were found in the composition of aqueous extracts from chokeberry leaves: polyphenols – 7.4±0.7, tannins – 4.6±0.5 mg/cm3. The safety of using A. melanocarpa leaves as raw material for phytofilm has been confirmed in heavy metal tests. The composition and film-forming ability of chokeberry leaves aqueous extract, including polyvinyl alcohol (098-15(G)) (6%), food grade gelatin P-11 (0.5%), glycerin (GOST 6259-75) (0.4%), colloidal silver solution 200 mg/dm3 (1%) has been established. A. melanocarpa leaves extract application to the film-forming solution increases the final vapor permeability by 48% and solubility by 14%. The model experiment shows the effect of using the created phytofilm in the reparation of linear wounds, manifested as significant decrease in their length by 30% by the fifth day, by 25% by the seventh day compared with the control, as well as normalization of the skin histological structure by the tenth day.

STUDY OF THE ANTISTATIC PROPERTIES OF MATERIALS TREATED WITH COLLOIDAL COMPOSITIONS BASED ON METAL NANOPARTICLES

The article provides a short overview of the application of metal nanoparticles in the textile indus- try, describes their properties and application`s fields. The definitions of electrification, electrostatic field, electric charge density are given. The application of processing of fabrics by polyurethane dispersion and metal nanoparticles in technological processes of textile materials finishing is justified. The objects of the study are cotton fabric`s samples with addition of synthetic fibres, colloidal solutions of silver and copper nanoparticles, aqueous polyurethane dispersion. The antistatic properties of the fabrics have been studied. The electrostatic field intensity of the samples was measured on the device ST-01, with the density of the electric charge calculating according to the intensity values. It has been experimentally established, that the processing of fabrics by solutions of nanoparticles of metals contributes to reduction of intensity of their electrostatic field to 65 %, compared with the initial samples. It is noted that treatment of fabrics by polyure- thane dispersion in combination with copper nanoparticles gives no clear antistatic properties to the blended fabrics.

Magnetron sputtering onto nonionic surfactant for 1-step preparation of metal nanoparticles without additional chemical reagents

Plasma-based sputtering onto liquids (SoL) is a straightforward approach for synthesizing small metal nanoparticles (NPs) without additional stabilizing reagents. In this work, nonionic surfactant Triton X-100 was used for the first time as a host liquid for the SoL process and the production of colloidal solutions of gold, silver and copper NPs was demonstrated. The average diameter of spherical Au NPs lies in the range from 2.6 to 5.5 nm depending on the conditions. The approach presented here opens the pathway to the production of concentrated dispersions of metal NPs of high purity that can be dispersed in water for future usage, therefore extending further the reach of this synthesis pathway.

Extremely Low Electromagnetic Frequency Modulation in Skin Rejuvenation and Regeneration

This clinical pilot study aims to show the effectiveness of homeopathic concentrations of the Colloidal Silver Solution (CSS) embedded with Extremely Low Electromagnetic Frequency (ELEMF) in skin rejuvenation and regeneration as well as a therapy of dyschromia. In this clinical observational pilot study, we utilized structured water infused with homeopathic concentrations of CSS and embedded with ELEMF to apply it to the dorsal part of the left hand, while the dorsal part of the right hand was used as a control. Ten subjects with Solar Lentigines were treated with the CSS for three weeks. The results are highly encouraging that CSS is successful in achieving this study’s objective.

Nitrogenous Bases in Relation to the Colloidal Silver Phase: Adsorption Kinetic, and Morphology Investigation

The interaction between inorganic nanoparticles and biological molecules is of great importance in the field of biosystems and nanomaterials. Here, we report the adsorption process of a heterocyclic organic compound (nitrogenous base) on a microporous carbon (C) in the presence of a colloidal silver solution (AgNP solution) as an accompanying substance. Analysis of the potential colloid–biomolecule interaction as well as the subsequent phenomenon of changes in the morphology of the colloidal system in the presence of selected nucleotides was investigated. Adenosine nitrogenous base (Anb) was selected as a model molecule of the building block of DNA and RNA. The adsorption process of nucleotides from one- and two-component systems was monitored by cyclic UV-VIS measurements for obtaining time-dependent profiles and estimating the kinetic characteristics of uptake. We demonstrate the temperature-dependent course of the adsorption process with visible nucleotide-AgNP morphology determinants. The experimental adsorption kinetics were analyzed using selected theoretical models (intraparticle diffusion model, multiexponential equation, and many others). On the other hand, obtained Anb/C and Anb/AgNP/C composites were characterized by various techniques suitable for material surface and morphology characterization: high-resolution transmission electron microscopy (HR-TEM and TEM/EDX), N2 physisorption measurements, and thermal analysis (thermogravimetric analysis (TGA)/differential scanning calorimetry (DSC) experiments).

Activity of Colloidal Silver Solution against Microorganisms Implicated in Ocular Infections

Endophthalmitis most likely originates from both planktonic bacteria suspended in the tear film and bacteria adherent to the conjunctiva and the eyelid. This study aimed to expand the research on the effectiveness of a colloidal silver solution (Silverix®) against ocular microorganisms. The activity of Silverix® was evaluated against methicillin-resistant Staphylococcus aureus, S. epidermidis, ofloxacin-resistant Pseudomonas aeruginosa, and Candida albicans strains, previously characterized for their antibiotic resistance and biofilm-forming capabilities. The microbial killing was estimated at various times in the presence and absence of colloidal silver solution against planktonic and biofilm-embedded cells. The results documented the efficacy of Silverix® on planktonic cells of S. aureus and S. epidermidis (2.49–2.87 Log CFU/mL reduction) and P. aeruginosa strains (3–4.35 Log CFU/mL reduction). On the contrary, C. albicans showed mild susceptibility. Regarding early biofilm, the ocular isolates were harder to kill (2–2.6 Log CFU/mL reduction) than the reference strains, whereas a similar decrease (3.1 Log CFU/mL reduction) was estimated for P. aeruginosa strains. The light microscope images of biofilms treated with colloidal solution confirmed the ability of Silverix® to destroy the biofilm.

Antimicrobial activity of different wound dressing products treated with silver

The main goal of this work was to optimize the method of processing wound dressing products (like gauzes, sanitary pads, cotton wool, compresses, and bandages) with a commercial silver colloidal solution (Koloid doo, Belgrade, Serbia) and then to examine the antimicrobial properties of the obtained items in order to potentially reach the market with new improved wound dressing products. The influence of different silver concentrations used for treatment on antimicrobial activity was investigated only against Escherichia coli. The antimicrobial activity of different types of materials treated with silver solutions of 30 ppm was investigated against Gram-negative bacteria Escherichia coli and Pseudomonas aeruginosa, Gram-positive bacteria Staphylococcus aureus, Bacillus subtilis, and Enterococcus faecalis, as well as the fungus Candida albicans. The microbial reduction of the tested materials loaded with a silver solution of 30 ppm (15-20 ?g of Ag on 1 g of fabric) against the Gram-negative bacteria E. coli and P. aeruginosa was almost maximal after 2 h of contact (i.e. 95 and 99 %, respectively). In the case of Gram-positive bacteria S. aureus, B. subtilis, and E. faecalis, a longer time is needed to completely eradicate bacteria (over 99 %). Antifungal activity testing against the fungus C. albicans gave moderate antifungal activity results.

Biopolymers as silver nanoparticle carriers for targeted drug delivery

Nowadays, biopolymers have acquired an important role in designing new therapeutics. Apart from being Active Pharmaceutical Ingredients (API), their physical aspect and pioneering features like anti-oxidant properties, have fascinated scientific community. In this context, the present wok reports engineering of silver nanoparticles by functionalizing them in-situ with polymers from plant extract for cervical cancer treatment. The aim of the work is to use biopolymer, folic acids, as silver nanoparticle carrier to deliver these nanoparticles at the cervical cancer site. Colloidal silver solution consisting of nanoparticles coated with polymers, theaflavins and folic acid, is synthesized using a physical approach. Biopolymers, theaflavins and folic acid, contained in the black tea leaves extract and green spinach leaves extract respectively, play the role of morphology tuner and drug carrier. Various characterization techniques confirmed the synthesis of double coated polydisperse colloidal silver consisting of pure, spherical, 6 nm-sized Ag NPs. The in-vivo study conducted at anti-Cancer Drug Screening Facility, ACTREC, Tata Memorial Centre, Navi Mumbai, suggested significant efficacy against cervical cancer. Targeted delivery of surface engineered nanoparticles across the tumor cells was confirmed by drug efficacy studies which proposed that as-synthesized formulation gave activity criteria (T/C = 0.49) very close to the standard significant value (T/C ≤ 0.42)). Folic acid is significant and efficient responder to folate receptors at cervical cancer site. Thus, use of biopolymers, as silver nanoparticles carrier, accomplishes efficient targeting of cervical tumor and gives a less toxic and cost-effective option to the existing therapeutics.

Comparative Analysis of Interaction Mode between MABA and Silver Nanoparticles in the Silver Colloidal Solution

Comparative Analysis of Interaction Mode between MABA and Silver Nanoparticles in the Silver Colloidal Solution

Synthesis and antibacterial activity of colloidal silver prepared by electrochemical method

Study was conducted on the electrochemical method of preparing colloidal silver at low DC voltage. A natural stabilizer was used as a carob bean gum from the carob bean. Using a UV-Vis spectrophotometer and a transmission electron microscope (TEM), colloidal silver (silver nanoparticles) was characterized. It is possible to produce colloidal silver of satisfactory quality by means of this electrochemical method. Silver nanoparticles have exhibited surface plasmon resonance as determined by UV-vis analysis. Based on the TEM analysis, the silver nanoparticles appear to be spherical except in sample E1, where they appear rod-shaped and micrometer-sized. Other three samples had particle sizes ranging from 23–52 nm. In a qualitative analysis of colloidal silver solutions, two types of antibacterial activity were observed. At all dilutions, some colloidal solutions showed better antibacterial activity against gram-positive bacteria (S. aureus, S. pyogenes, E. faecalis) while others displayed better antibacterial activity against gram-negative bacteria (S. enteridis, P. aeruginosa, E. coli).

Ultra-sonication-enhanced green synthesis of silver nanoparticles using Barleria buxifolia leaf extract and their possible application

The main aim of the study, green route to the synthesis of silver nanoparticles (AgNPs) is a new technique that has recently gained popularity due to several advantages over conventional chemical methods. The objective of the study was focused on the green synthesis of AgNPs using Barleria buxifolia leaf extract via a rapid and eco-friendly ultrasonic-assisted technique. The obtained AgNPs were characterized using ultraviolet–visible (UV–Vis) absorption spectrum of the organically reduced silver showed a surface plasmon peak at 435 nm, characteristic for silver colloidal solutions. UV–Vis absorption spectrum, scanning electron microscopy (SEM), transmission electron microscopy (TEM), and energy-dispersive X-ray spectroscopy (EDS) analysis showed that the obtained AgNPs were dispersed spheres with a uniform size of 80 nm. Furthermore, the Fourier-transform infrared spectroscopy (FTIR) and X-ray powder diffraction (XRD) analysis indicated that the surface of the obtained AgNPs was covered with organic molecules in plant extracts. Green synthesized AgNPs showed the highest antioxidant, antibacterial and anti-biofilm activity than a plant extract. In vitro anticancer assay demonstrated half-maximal inhibitory concentration (IC50) values of 31.42, 30.67, 51.07 and 56.26 µg/mL against MCF-7, HeLa and HepG2 cancer cell lines, respectively, which confirms its potent anticancer action. The biocompatibility of green synthesized AgNPs is confirmed by their lack of cytotoxicity against normal human cells. The potent bioactivity exhibited by the green synthesized AgNPs leads towards the multiple use as antioxidant, antibacterial, anti-biofilm and cytotoxic agent.

Evaluation of efficacy of colloidal silver particles against late blight of potato (Phytophthora infestans L.)

Colloidal silver was synthesized by the ‘bottom up’ approach of wet chemical method and analyzed bylaser Dynamic Light Scattering (DLS). The colloidal silver solution synthesized was having a particle sizewith a mean diameter of 149.4 nm. Tested the efficacy of synthesized colloidal silver particles under in vitroconditions (10 ppm, 25 ppm, 50 ppm,100 ppm 250 ppm and 500 ppm) against Phytophthora infestans. Amongthe different concentrations maximum inhibition of mycelial growth was recorded at higher concentrations(250 ppm and 500 ppm). To know the further effectiveness of higher concentrations of colloidal silverparticles were tested alone (250 ppm and 500 ppm) and in combination with fungicides (Cymoxanil 8 % +mancozeb 64 % WP@ 0.2 % and Dimethomorph @ 0.2%) under field conditions. The spray solutions ofcolloidal silver at 500 ppm recorded significantly less late blight disease severity at 90 days after sowing(DAS) (42.22 PDI) when compared to @ 250 ppm (60.74 PDI) and untreated plants (75.56 PDI). The foliarapplication of colloidal silver @ 500 ppm is found on par with Cymoxanil 8 % + mancozeb 64 % WP@ 0.2% whereas superior over Dimethomorph 50% WP @ 0.2%. Further, colloidal silver both @ 250 ppm and 500ppm when used in combination with fungicides could not significantly complemented the efficacy offungicides viz., Cymoxanil 8 % + Mancozeb 64 % WP @ 0.2 % and Dimethomorph 50% WP @ 0.2% inreducing the late blight disease severity at 90 DAS, but recorded significantly less disease severity thanuntreated control plants. Examined the biochemical response of plant defense mechanism pertaining todefense related enzymesin treated and untreated plants. The increased activity of peroxidase (PO) (1.5mg/g), polyphenol oxidases (PPO) (0.01 mg/g) and phenylalanine ammonia lyase PAL (1.5 mg/g) wasobserved in late blight infected potato plants treated with colloidal silver particles @ 500ppm and incombination of 0.2 per cent of Cymoxanil 8 % + Mancozeb 64 % WP fungicide.

Synergistic Effect of Field Emission Properties on Growth of CNTs by One-Pot Preparation of Various Concentrations Composite Catalyst

Multi-walled carbon nanotubes (MWCNTs) were grown on Silicon (Si) substrate by using low-pressure chemical vapor deposition (LPCVD) technique where iron (Fe) and silver (Ag) colloidal solution act as a catalyst were prepared by chemical route. The as-prepared solutions in varied concentrations were deposited on a Si substrate using a spin coating process at 700[Formula: see text]rpm. The purpose of Fe in composite catalysts is to have high carbon solubility and diffusion rate, and Ag utilization can change catalyst activity temperature and enhance carbon yields. In this work, we demonstrate the growth of carbon nanotubes (CNTs) on different catalyst concentrations ([Formula: see text]Fe/[Formula: see text]Ag), ([Formula: see text]Fe/[Formula: see text]Ag), ([Formula: see text]Fe/[Formula: see text]Ag) and ([Formula: see text]Fe/[Formula: see text]Ag) catalytic films. Field Emission Scanning Electron Microscopy (FESEM) was used to image the morphologies of various catalyst concentrations MWCNTs. The natures of the synthesized CNTs were determined using Raman spectroscopy and it was revealed that as-prepared CNTs are MWCNTs due to the absence of radial breathing mode (RBM). Raman spectroscopy demonstrated the lower ID/IG ratio (Ratio of the intensity of D-Raman peak and G-Raman peak) of ([Formula: see text]Fe/[Formula: see text]Ag) MWCNTs. The ID/IG ratio for ([Formula: see text]Fe/[Formula: see text]Ag) catalyzed MWCNTs was 0.76, while the ID/IG ratio for ([Formula: see text]Fe/[Formula: see text]Ag) catalyzed MWCNTs was 0.89. The ([Formula: see text]Fe/[Formula: see text]Ag) catalyzed MWCNTs were found to be more defective as compared to other. Electron Emission from ([Formula: see text]Fe/[Formula: see text]Ag) catalyzed MWCNTs were much stronger than from other samples, as demonstrated by Field Emission measurement using diode configuration. The turn-on field for ([Formula: see text]Fe/[Formula: see text]Ag) catalyzed MWCNTs was (0.92 V/[Formula: see text]m) which is slightly lower than that of ([Formula: see text]Fe/[Formula: see text]Ag) catalyzed MWCNTs (1.83 V/[Formula: see text]m), indicating superior enhancement.

Detection of molecular vibrations of atrazine by accumulation of silver nanoparticles on flexible glass fiber as a surface-enhanced Raman plasmonic nanosensor

Surface-Enhanced Raman Spectroscopy (SERS) is a sensitive vibration spectroscopy method applied to analyze a variety of analytes, including toxins and pesticides. The SERS method is an accurate method for detecting significantly low concentrations of biomaterials and chemicals. In the present study, in order to detect atrazine pesticide, the glass fiber substrates coated with silver nanoparticles have been used as SERS plasmonic nanosensors. First, silver nanoparticles were prepared by applying a chemical approach named the Tollens' method, and the SERS plasmonic substrates (SPS) were fabricated by depositing the colloidal silver solution on a glass fiber substrate. The SERS plasmonic nanosensors were fabricated by self-assembling the silver nanoparticles and after functionalization of glass fiber substrate using 3-aminopropyl triethoxysilane (APTES). For this purpose, silver nanoparticles were chemically prepared, and their size distribution was determined to be 140–150 nm using dynamic light scattering (DLS). Ultraviolet–visible spectroscopy was applied for the optical characterization of colloids of silver nanoparticles and the prepared substrates. The results indicate the displacement of the plasmonic peak toward longer wavelengths after self-assembly of the nanoparticles. Field emission scanning electron microscopy images indicated the non-uniform distribution of silver nanoparticles on the surface of glass fiber substrates. Atrazine pesticide was employed as an analyte to investigate the performance of SERS plasmonic substrates (SPS). The detection limit of SPS for detecting atrazine pesticide was equal to 10−12 M, and the average relative standard deviation for ten repeated measurements was obtained to be 4.02%. With reducing the solution concentration to 10−12 M, the intensity of Raman modes decreased significantly so that only some peaks were clear. Moreover, the quantum mechanics calculation and molecular dynamics simulation were performed to clarify the molecular interactions between atrazine and silver nanoparticles. By increasing the concentration of atrazine, the Lennard-Jones potential was increased following the experimental results of Raman spectroscopy.

Estimation of biocidal effect of metal and bioelement nanoparticles in a unicellular eukaryotic test system

The results of the study of biocidal properties of silver, copper and silicon dioxide nanoparticles are presented. Questions about the safety of nanocomponents in connection with their unstudied impact on the environment are considered. To evaluate the biocidal effect of noble metal nanoparticles and bioelements, a unicellular eukaryotic test-system, represented by a ciliated protist microorganism Paramecium caudatum inhabiting pond water bodies, was used. It was found that solutions of noble metal nanoparticles and bioelements are not bioinert and biostimulating. Colloidal solutions of silver, copper and silicon dioxide nanoparticles have a biocidal effect and show a similar dosedependent effect if the concentration of nanoparticles in the initial colloidal solutions is the same (300 µg/ml). The colloidal silver solution is characterized by a more pronounced toxic activity in a unicellular protist biological model, since full biocidal activity against paramecium is provided by dilutions of the colloidal solution of nanoparticles to the value 1: 6 of the initial one. Compared to it, solutions of copper nanoparticles and silicon oxide have a biocidal index of 100% achieved only in values of two- or three-times dilution of the initial solution. Colloidal solutions of nanoparticles in concentrations that do not cause complete mortality of the infusoria (1: 5 of the original for copper and silicon oxide nanoparticles and 1: 7 of the original for silver nanoparticles) inhibit their reproduction intensity by approximately the same value of 55-61% (paramecium reproduction intensity index of 0.455 to 0.390 respectively).