Antibacterial Activity of Sustainable Thymol Nanoemulsion Formulations Against the Bacterial Blight Disease on Cluster Bean Caused by Xanthomonas axonopodis.

The aim of the present study was nanoencapsulation of thymol to improve its poor water solubility and preservation of encapsulated thymol against environmental conditions. Another goal of the current investigation was to assess the antibacterial activity of thymol nanoemulsion as a sustainable biopesticide to control the bacterial blight of cluster bean. An oil-in-water (o/w) nanoemulsion containing thymol was prepared by a high-energy emulsification method using gum acacia and soya lecithin as natural emulsifiers/surfactants. The characterization of thymol nanoemulsion was carried out using dynamic light scattering (DLS), transmission electron microscope (TEM) and Fourier transform infrared spectroscopy (FTIR). A mean particle size of about 83.38 nm was recorded within 10 min of sonication. The stability analysis of optimized nanoemulsion showed kinetic stability up to two months of storage at room temperature. The thymol nanoemulsion was found to be spherical with a size ranging from 80-200 nm in diameter using transmission electron microscopy. Fourier transform infrared spectroscopy was used to study the molecular interaction between emulsifier/surfactant and thymol. The antibacterial studies of thymol nanoemulsion (0.01-0.06%, v/v) by growth inhibition analysis showed a potential antibacterial effect against Xanthomonas axonopodis pv. cyamopsidis (18-0.1 log CFU/ml). Further, in field experiments, foliar spray of the different concentration of thymol nanoemulsion (0.01-0.06%, v/v) significantly increased the percent efficiency of disease control (25.06-94.48%) and reduced the disease intensity (67.33-4.25%) of bacterial blight in cluster bean.

Robust and direct electrochemical sensing of arsenic using zirconia nanocubes.

The presence of heavy metal ions in the environment and in food items can severely harm human health. Thus, simple, reliable, sensitive, quick, and accurate methods for their detection must be developed as a means to improve healthcare worldwide. To this end, a robust method was developed for the direct sensing of arsenic(iii) in control and real environmental samples (at neutral pH) by a gold electrode that was modified with zirconia nanocubes synthesized via a facile hydrothermal route. This sensing system was used to build a sensing profile for arsenic ions after characterization of their elemental, optical, chemical, and morphological behavior. Electrochemical sensing of arsenic was achieved by cyclic voltammetry (CV) and chronoamperometry with an ultra-sensitivity of 550 nA cm(-2) ppb(-1) and a detection limit of 5 ppb (linear range of 5-60 ppb with a response time below 2 s). Although this system experienced small interference from Cd ions, the results of the real sample analysis were comparable to those of other standard techniques. The proposed method is advantageous and can be used to assess the toxicity of water, food, and other environmental samples without requiring any toxic solutions and/or gasses in any of the analytical steps. Moreover, due to its low price, portability, and easy mass production, it can be adopted for use in screen-printed electrodes.

Hybrid surfactants decorated with copper ions: aggregation behavior, antimicrobial activity and anti-proliferative effect.

In the present study, the emphasis is laid on the self aggregation behavior of copper based inorganic-organic hybrids in aqueous media. The two complexes, cationic hexadecyl pyridinium trichloro cuprate (1 : 1), [Cp](+)[CuCl3](-), and bishexadecylpyridinium tetrachloro cuprate (2 : 1), [Cp2](2+)[CuCl4](2-), were synthesized using the ligand insertion method. The complexes were characterized using elemental analysis, Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), nuclear magnetic resonance (NMR) and thermogravimetric analysis. The copper complexes were found to be thermally stable, and in the solid state, they possessed the perovskite arrangement with [Cp2](2+)[CuCl4](2-) exhibiting superior stability and crystallinity. The self aggregation behavior of the prepared complexes was analyzed in solution phase (in aqueous medium) using surface tension, conductivity, XRD and small angle neutron scattering (SANS). The results show that the presence of copper as a co-ion in both the stoichiometries results in lower critical micellization concentrations than their precursor. Micellization was thermodynamically spontaneous and micelles formed were ellipsoidal in shape and underwent a prolate ellipsoidal growth with an increase in the concentration of metallosurfactant, as estimated from the SANS. Furthermore, these metallosurfactants were investigated for biocompatibility (using hemolytic assay), antimicrobial activity (fungus and bacteria) and cytotoxicity using human cancerous cells. The hemolysis activity was found to depend on the aggregated state of the metallosurfactants, displaying the highest activity in the monomeric state, and the minimum for post micellar concentrations. The surfactants were found to enhance the antibacterial activity by twofold or more, with the addition of metal in both the stoichiometries. On the contrary, for anticancer and antifungal activities, barely any regular trend or generalization could be obtained. Nevertheless, the copper complexes exhibited high IC50 values for fR2 (healthy cells) signifying their higher safety in comparison to the cancerous cells.

Utilization of carbon nanotubes for the removal of rhodamine B dye from aqueous solutions.

Carbon nanotubes (CNTs) are attracting increasing research interest as promising adsorbents for harmful cations, anions, and other organic and inorganic impurities present in natural sources of water. This study examined the feasibility of removing Rhodamine B dye from aqueous solutions using multi walled carbon nanotubes (MWCNTs) synthesized by chemical vapor deposition (CVD) method. The effects of dye concentration, pH and contact time on adsorption of direct dye by CNTs were also evaluated. The study used the Langmuir and Temkin isotherms to describe equilibrium adsorption. Additionally, pseudo second-order model was adopted to evaluate experimental data and thereby elucidate the kinetic adsorption process. The adsorption percentage of dye increased as contact time increased. Conversely, the adsorption percentage of dye decreased as dye concentration increased. The pseudo second-order model best represented adsorption kinetics. The capacity of CNTs to adsorb Rhodamine B was 65-90% at different pH values.

Nanotechnology-based water treatment strategies.

The most important component for living beings on the earth is access to clean and safe drinking water. Globally, water scarcity is pervasive even in water-rich areas as immense pressure has been created by the burgeoning human population, industrialization, civilization, environmental changes and agricultural activities. The problem of access to safe water is inevitable and requires tremendous research to devise new, cheaper technologies for purification of water, while taking into account energy requirements and environmental impact. This review highlights nanotechnology-based water treatment technologies being developed and used to improve desalination of sea and brackish water, safe reuse of wastewater, disinfection and decontamination of water, i.e., biosorption and nanoadsorption for contaminant removal, nanophotocatalysis for chemical degradation of contaminants, nanosensors for contaminant detection, different membrane technologies including reverse osmosis, nanofiltration, ultrafiltration, electro-dialysis etc. This review also deals with the fate and transport of engineered nanomaterials in water and wastewater treatment systems along with the risks associated with nanomaterials.

Development and evaluation of eco-friendly carvacrol nanoemulsion as a sustainable biopesticide against bacterial leaf blight of cluster bean.

BACKGROUND: The study of carvacrol plant antibacterial components has recently become a hot topic in modern farming. Carvacrol industrial applications are restricted by their physicochemical instability and partial solubility in water. In the present study, an ultrasonic emulsification method was used to prepare a carvacrol nanoemulsion (CAR-NE) employing nonionic surfactants. The CAR-NE was characterized using a dynamic light scattering (DLS) instrument and transmission electron microscopy (TEM). The goal of this work was nanoencapsulation of carvacrol to improve its aqueous solubility and preservation of the encapsulated compound against climatic conditions. Another aim of the present study was the evaluation of the growth-promoting effects and antibacterial potential of CAR-NE against bacterial leaf blight of cluster bean. RESULTS: CAR-NE showed a hydrodynamic diameter, ZP and PDI index of 43.88 ± 4.30 nm, -47.8 ± 0.23 mV and 0.246 ± 0.04, respectively. The spherical shape morphology of CAR-NE was confirmed by TEM imaging. Minimum inhibitory concentrations (MIC) and minimum bactericidal concentrations (MBC) of the CAR-NE were 20 and 160 µL mL-1 (respectively) against Xanthomonas axonopodis pv. cyamopsidis. Additionally, the antibacterial potential of CAR-NE was evaluated for controlling bacterial blight of cluster bean in fields. The disease severity in the negative control plants (water) was 84%, but that in the CAR-NE 160 (µL mL-1 ) was remarkably low at 14%, nearly the same as the positive control (streptomycin sulfate). CONCLUSION: The shelf-life of CAR-NE was 2 months at room temperature without any appreciable changes in hydrodynamic diameter and zeta potential. Consequently, plants treated with CAR-NE 160 showed substantial improvement in plant growth. © 2023 Society of Chemical Industry.

Spherical silver oxide nanoparticles for fabrication of electrochemical sensor for efficient 4-Nitrotoluene detection and assessment of their antimicrobial activity.

This research article reports an economic and affordable microwave-assisted synthesis of spherical silver oxide nanoparticles (Ag2O NPs) (80-90 nm) for an efficient electrochemical sensing of a hazardous organic pollutant 4-nitrotoluene (4-NT). Such well-characterized Ag2O NPs were utilized to modify gold (Au) electrode in order to fabricate Ag2O-NPs/Au sensor to detect 4-NT using cyclic voltammetry (CV) and linear sweep voltammetry (LSV) techniques. Ag2O-NPs/Au sensor exhibited a distinguished electrical response as a function of varying 4-NT concentration in neutral medium samples. Ag2O-NPs/Au sensor demonstrated an ultrahigh sensitivity as 15.33 µA (µM)-1 cm-2, a low detection limit of 62.3 nM, and linear response in detection ranges of 0.6-5.9 µM and 37-175 µM. The sensing performance of fabricated Ag2O-NPs/Au sensor is reproducible, reusable, selective in presence of other chemical species, and validated using real samples. The Ag2O/Au sensor had much rapid and easy fabrication process and offered much lower LOD for 4-NT detection than many previously reported sensors. Along with efficient electrochemical activity, the spherical Ag2O NPs also exhibit remarkable antimicrobial activity against harmful gram negative Escherichia coli (E. coli) and gram positive Staphylococcus aureus (S. aureus) bacteria. Herein projected efficient Ag2O-NPs/Au electrochemical sensor for 4-NT is affordable with the capability of scaling up to perform point-of-care 4-NT testing needed for successful environmental monitoring and water quality assurance.

Microwave-assisted assembly of Ag2O-ZnO composite nanocones for electrochemical detection of 4-Nitrophenol and assessment of their photocatalytic activity towards degradation of 4-Nitrophenol and Methylene blue dye.

4-Nitrophenol (4-NP) is an extensively utilized industrial chemical and one of major toxic water pollutant. Therefore, there is an urgent need to monitor the levels of 4-NP from environmental samples as well as its eradication are extremely important. Keeping this as a motivation, this research for the first-time reports microwave-assisted cost-effective synthesis of silver oxide (Ag2O)-zinc oxide (ZnO) composite nanocones (CNCs, 80-100 nm) for simultaneous electrochemical detection and photodegradation of 4-NP from aqueous solutions. The Ag2O-ZnO CNCs modified gold electrode was fabricated for electrochemical detection of 4-NP. Such fabricated sensor exhibited a sensitivity of 1.6 µA µM-1cm-2, wide linear detection range of 0.4-26 µM & 28-326 µM, and a low limit of detection of 23 nM. The sensor also exhibited good selectivity in real water samples. Also, an outstanding photocatalytic performance of Ag2O-ZnO CNCs was evaluated towards UV-assisted degradation of 4-NP and organic water pollutant dye, methylene blue. The Ag2O-ZnO CNCs exhibited excellent electro- and photocatalytic activities due to the formation of p-n nano-heterojunction comprising of p-type Ag2O and n-type ZnO semiconductor nanoparticles within the composite. Therefore, herein reported smart CNCs can be projected as applied nano-system for cost-effective and rapid simultaneous detection and removal of 4-NP from aqueous solutions. Such nano-system can be useful for industrial application where detection and removal of 4-NP is a key issue to resolve.

A flower-like ZnO-Ag2O nanocomposite for label and mediator free direct sensing of dinitrotoluene.

2,4-Dinitrotoluene (2,4-DNT) is a nitro aromatic compound used as a raw material for trinitrotoluene (TNT) explosive synthesis along with several other industrial applications. Easy, rapid, cost-effective, and selective detection of 2,4-DNT is becoming essential due to its hepato carcinogenic nature and presence in surface as well as ground water as a contaminant. Keeping this in view, this research, for the first-time, reports the synthesis of novel ZnO-Ag2O composite nanoflowers on a gold (Au) substrate, to fabricate an electrochemical sensor for label-free, direct sensing of 2,4-DNT selectively. The proposed ZnO-Ag2O/Au sensor exhibits a sensitivity of 5 µA µM-1 cm-2 with a low limit of detection (LOD) of 13 nM, in a linear dynamic range (LDR) of 0.4 µM to 40 µM. The sensor showed reasonably high re-usability and reproducibility, with reliable results for laboratory and real-world samples.

Manganese Oxide Nanochips as a Novel Electrocatalyst for Direct Redox Sensing of Hexavalent Chromium.

In order to maintain a healthy organisation of bionetworks, both qualitative and quantitative estimation of hexavalent chromium in food and beverage samples is required based on proper quality control and assurance. Nonetheless, conventional quantitation techniques for hexavalent chromium generally suffer from certain limitations (e.g., the need for expertise, costly equipment, and a complicated procedure). This research was performed to elaborate a novel method to quantify hexavalent chromium based on an electrochemical cyclic voltammetry technique. To this end, nanochips of manganese oxide (Mn3O4: approximately 80-90 nm diameter and 10 nm thickness) were synthesized using a chemical method and characterized with spectroscopic and microscopic approaches. These nanochips were employed as proficient electrocatalytic materials in direct redox sensing of hexavalent chromium in both real samples and laboratory samples. Manganese oxide nanochips felicitated large surface area and catalytic action for direct electrochemical reduction of hexavalent chromium at electrode surface. This fabricated nanochip sensor presented a detection limit of 9.5 ppb with a linear range of 50-400 ppb (sensitivity of 25.88 µA cm-2 ppb-1).

Enhanced antibacterial profile of nanoparticle impregnated cellulose foam filter paper for drinking water filtration.

Filtration is a promising water treatment method to purify drinking water. To develop highly efficient drinking water filter paper, water-resistant cellulose foam paper with a high wet strength property was fabricated using diverse metal oxide (e.g., copper oxide (CuO), zinc oxide (ZnO), and silver oxide (Ag2O)) nanoparticles. These nanoparticles were synthesized using the hydrothermal reaction method. Their morphological structures were studied using a field emission scanning electron microscope (FESEM). The presence of coated nanoparticles on the cellulose foam filter was verified by energy dispersive X-ray spectroscopy (EDX) methods. The antibacterial performance of different types of modified cellulose foam filters was studied against E. coli, P. aeruginosa, B. subtilis, and B. cereus strains using the zone of inhibition test. The antibacterial profile of the cellulose foam filter impregnated with Ag2O nanoparticles, when tested against different types of bacteria, exhibited higher antibacterial activity than the cellulose foam filter impregnated with ZnO and CuO nanoparticles.

DNA interaction, anti-proliferative effect of copper oxide nanocolloids prepared from metallosurfactant based microemulsions acting as precursor, template and reducing agent.

In the present study, we have synthesized mixed cuprous/copper oxide nanosuspensions by metallosurfactant based microemulsion technique. Three metallosurfactants were synthesized which includes two non-ionic double chained metallosurfactants with C12, C16 chains with coordinated copper i.e. Cudda and Cuhexa, respectively. Another cationic double chained metallosurfactant with loosely bound metal (Cuctac) was also prepared. The prepared metallocomplexes were characterized using FTIR, elemental analysis, and NMR. The effect of the position of metallosurfactant in microemulsion on the fabrication and properties of nanosuspensions was elucidated. In this method, no external reducing agent and capping agent were added and tween 80 acted both as reducing and stabilizing agent for the nanoparticles. The synthesized nanoparticles were characterized and it was observed that mixed copper and cuprous oxide particles are present in colloidal suspension for all the three studied metallosurfactants. The kinetics of formation of mixed copper/cuprous oxide nanosuspensions (Ns) and their stability was estimated using Uv-visible spectroscopy. Further, the binding and interactions of copper nanosuspensions with calf Thymus DNA (CT-DNA) were assessed using Uv-vis spectroscopy, circular dichroism and gel electrophoresis. Additionally, the antioxidant activity of the Cu Ns was checked using DPPH assay. The role of positive charge on nanoparticles as evaluated from Zeta potential was responsible for DNA affinity. The DNA conformational changes in the presence of nanosuspensions and relevant scavengers were investigated. Further, the anti-proliferative activity of copper Ns was assessed using HeLa cells and Cuhexa derived Ns were proved to be active with highest activity at a low concentration and were nontoxic towards normal cell lines. In summary, this work demonstrates a softer approach for the synthesis of copper nanosuspensions with a size range of 2-5 nm and evaluated the role of type and structure of metallosurfactant on size, stability of particles and anti-proliferative activity.

Modification of cellulose foam paper for use as a high-quality biocide disinfectant filter for drinking water.

Development of a foam-formed cellulose filter paper with high wet strength was carried out for application as a drinking water filter. The wet strength and antimicrobial activity of cellulose foam paper against several bacteria species (Bacillus subtilis MTCC 441 (Gram +ve), B. cereus NCDC 240 (Gram +ve), Pseudomonas aeruginosa NCDC 105 (Gram -ve), Klebsiella pneumonia NCDC 138 (Gram -ve), and Escherichia coli MTCC 40 (Gram -ve)) were investigated. The morphology and structure of the cellulose foam paper were characterized using scanning electron microscopy (SEM). The results of our study confirmed that glutaraldehyde solution or 1,2,3,4-butanetetracarboxylic acid (BTCA) added to cellulose foam paper pretreated with cationic polyacrylamide (C-PAM) provided very high and stable wet strength performance together with excellent antimicrobial properties.

Development of nanoformulation approaches for the control of weeds.

The nanoformulation of pesticides has the potential to increase food productivity, while resolving the drawbacks of conventional agrochemicals, which have negative environmental impacts. In this study, herbicide (metsulfuron methyl)-loaded pectin (polysaccharide) nanoparticles were synthesized and evaluated for herbicidal activity and cytotoxicity. The optimum formulation of nanoparticles was obtained using the Central Composite Design. The basic properties (mean particle size, stability, morphology, and interaction between polymer and herbicide) were characterized using a particle size analyzer (PSA), zeta potential, transmission electron microscopy (TEM), and Fourier Transform infrared spectroscopy (FTIR), respectively. The nanoparticles were found to be in size range of 50-90nm with zeta potential value of -35.9mV. The herbicide loading and herbicide encapsulation efficiency of the nanoparticles were determined to be 6.30% and 63±2%, respectively. The cytotoxicity of the herbicide-loaded nanoparticles was evaluated using healthy cell lines (Vero cell lines) and compared with that of commercial herbicide. In addition, an in-field evaluation of our nanoformulation's effects on the Chenopodium album plant was performed using a pectin nanocarrier. The results showed that application of herbicide-loaded nanoparticles could be used to reduce the use of herbicides with improved efficacy and environmental safety.

Metformin-loaded alginate nanoparticles as an effective antidiabetic agent for controlled drug release.

OBJECTIVES: Present modalities for the diagnosis and treatment of diabetes still suffer from certain limitations such as erratic absorption, need of high dose, poor sensitivity or specificity, resistance, substantial morbidity and mortality, long-term complications, and patient-to-patient variability with lifetime treatment. METHODS: This study focused on the development of a water-in-oil-in-water metformin nanoemulsion as an effective method in diabetes treatment. As a Biopharmaceutics Classification System (BCS) class III drug, metformin is hydrophilic in nature with high solubility and poor absorption characteristics. To simultaneously facilitate gastrointestinal absorption and intestinal permeability, metformin was loaded into alginate nanocapsules prepared by an emulsion cross-linking technology. KEY FINDINGS: These prepared metformin-loaded alginate nanoparticles (MLANs) were characterized using transmission electron microscopy (TEM), Fourier transform infrared (FTIR) spectroscopy, and photon correlation spectroscopy (PCS)-based particle size analysis. CONCLUSIONS: The drug loading and encapsulation efficiency in MLANs were 3.12 mg (the amount of metformin added in 100 mg of nanoparticles) and 78%, respectively. The results of in-vitro drug release studies and in-vivo efficacy tests (using animal models) demonstrated enhanced efficiency and response of MLANs relative to pure metformin. The efficacy of MLANs (46.8 mg/kg) was overall about three times higher than that of pure metformin150 mg/kg.

Synthesis and optimization of ceftriaxone-loaded solid lipid nanocarriers.

The use of nanocarriers to enhance drug delivery efficacy has been increasing in the healthcare field due to their tunable surface properties. In this study, ceftriaxone-loaded solid lipid nanoparticles (CL-SLNPs) were synthesized using a water-in-oil-in-water (w/o/w) type double emulsification method. The formulation was optimized using response surface methodology (RSM) and was characterized using transmission electron microscopy (TEM), photon correlation spectroscopy (PCS), and UV-vis and Fourier transform infrared (FTIR) spectroscopy. The CL-SLNPs were of spherical shape, 15-20nm in size, and retained the properties of the drug or other constituents/ingredients after loading. The prepared nanoformulation offered sustained drug release after 24h, while ceftriaxone sodium followed a burst release. Antibacterial activity of the nanoformulation was evaluated against different gram-positive and gram-negative bacterial strains. The minimum inhibitory concentration of CL-SLNPs against Pseudomonas aeruginosa was determined as 31µg/mL.

Coencapsulation of hydrophobic and hydrophilic antituberculosis drugs in synergistic Brij 96 microemulsions: a biophysical characterization.

A microemulsion has been formulated to coencapsulate antituberculosis drugs to solve the issue of stability of rifampicin (RIF) in the presence of isoniazid (INH) and pyrazinamide (PZA). The structural transition, solubilization locus, and quantitative release of drugs without interference have been estimated. Derivative absorbance spectroscopy, especially ratio derivative and double divisor ratio derivative methods, has been employed for estimating the release. The coencapsulation of the anti-tuberculosis drugs were carried out in single, binary, or ternary mixtures and occupy the same solubilization sites in multiple drugs microemulsion systems as in the case of single drug-loaded systems. INH and PZA obey the diffusional (Fickian) release mechanism, whereas RIF shows anomalous release. Resazurin assay and agar well diffusion method were adopted for cytotoxicity analysis and antimicrobial activity, respectively. Cytotoxicity was found to be dependent on concentration and on colloidal structure of microemulsion.

Multi walled carbon nanotubes as sorbent for removal of crystal violet.

Carbon nanotubes (CNTs) possess high surface active site to volume ratio as well as controlled pore size distribution that make them high profile material with an exceptional sorption capability and high sorption efficiency compared to conventional adsorbents. In the present paper, multi walled carbon nanotubes were synthesized by chemical vapor deposition (CVD) method and were further used for the removal of dye crystal violet. Microscopic and spectroscopic techniques were used for characterization. The systematic assessments of the pH and effect of adsorbent on different concentrations of dye with respect to contact time were examined. Langmuir and Temkin models were used to describe the isotherm studies.

Synthesis, characterization and on field evaluation of pesticide loaded sodium alginate nanoparticles.

The pesticide formulations in use these days have their own burdens on farming systems in terms of their accumulation in soil and ecosystems which can have serious effects on mankind and living organisms. With the help of nanotechnology, controlled release of agrochemicals, site targeted delivery of various macromolecules desired for improved plant disease resistance, enhanced plant growth and efficient nutrition utilization can be easily done. Nanoencapsulation has an advantage of safer handling and more efficient use of pesticides with less exposure to environment that guarantees ecoprotection. In plant entomology, nanotechnology targets specific agricultural problems in plant pests interaction and provide new ways for crop protection. The present investigation involves the delivery of imidacloprid (admire) pesticide in the form of nanoformulation to plants and investigation of their ultimate effects which can provide some insight for the safe use of this novel technology for the improvement of crop yield and safety.

Quinapyramine sulfate-loaded sodium alginate nanoparticles show enhanced trypanocidal activity.

AIM: To reduce the dose, toxic effects and to ensure sustained release of quinapyramine sulfate (QS), a highly effective drug against Trypanosoma evansi. MATERIALS & METHODS: QS-loaded sodium alginate nanoparticles (QS-NPs) were formed by emulsion-crosslinking technology using dioctyl-sodium-sulfosuccinate and sodium alginate. The formulation was characterized for size, stability, morphology and functional groups by a zetasizer, scanning electron microscopy, atomic force microscopy, transmission electron microscopy and Fourier transform infrared spectroscopy. In vitro safety and toxicity studies were performed by metabolic assay in Vero cell lines, and in vivo efficacy was evaluated in mice. RESULTS: QS-NPs were <60 nm with 96.48% entrapment efficiency and 3.70% drug loading. The formulation showed an initial burst effect followed by slow drug release in accordance with quasi-Fickian Higuchi diffusion mechanism. QS-NPs were much less toxic and able to clear the parasite at a much lower concentration than QS. CONCLUSION: The QS-NPs synthesized are safe, less toxic and highly effective compared with QS.