Chitosan Capped Silver Nanoparticles Research Articles

Silibinin-loaded chitosan-capped silver nanoparticles exhibit potent antimicrobial, antibiofilm, and anti-inflammatory activity against drug-resistant nosocomial pathogens

Nanoparticles capped with natural products can be a cost-effective alternative to treat drug-resistant nosocomial infections. Therefore, silibinin-loaded chitosan-capped silver nanoparticles (S-C@AgNPs) were synthesized to evaluate their antimicrobial and anti-inflammatory potential. The S-C@AgNPs plasmon peak was found at 430 nm and had a particle size distribution of about 130 nm with an average hydrodynamic diameter of 101.37 nm. The Scanning Electron Microscopy images showed the presence of sphere-shaped homogeneous nanoparticles. The Fourier Transform Infrared Spectroscopy analysis confirmed the loading of silibinin and chitosan on the AgNPs surface. The minimum inhibitory concentration of the S-C@AgNPs was reported between 3.12 μg/ml to 12.5 μg/ml and a minimum bactericidal concentration between 6.25 μg/ml to 25 μg/ml against drug-resistant nosocomial pathogens. Moreover, concentration-dependent significant inhibition of the biofilm formation was reported against P. aeruginosa (70.21%) and K. pneumoniae (71.02%) at 30 μg/ml, and the highest destruction of preformed biofilm was observed at 100 μg/ml against P. aeruginosa (89.74%) and K. pneumoniae (77.65%) as compared to individual bacterial control. Additionally, the fluorescence live/dead assay for bacterial biofilm confirmed that 100 µg/ml effectively inhibits the biofilm formed by these pathogens. S-C@AgNPs also showed anti-inflammatory activity, which is evident by the significant decrease in the proinflammatory cytokines and chemokines level in THP1 cells treated with LPS. This study concluded that S-C@AgNPs have potent antimicrobial, antibiofilm, and anti-inflammatory properties and could be a potential option for treating drug resistant nosocomial infections.

Direct sunlight induced room temperature synthesis of anticancer and catalytic silver nanoparticles by shrimp shell waste derived chitosan

The use of marine waste derived chitosan (CS) for the synthesis of nanomaterials is considered as one of the effective routes for bio-waste management and recovering functional products. Herein, CS capped silver nanoparticles (Ag NPs-CS) with potential anticancer and dye pollutants adoption properties have been synthesized photochemically under direct sunlight. To obtain, CS, shrimp shell waste was subjected to a serious of standard demineralization, deproteinization and deacetylation processes. The electronic absorption peak (400 nm) denoting surface plasmonic resonance of Ag NPs and infrared peaks relevant to CS (3364 cm−1 of OH/NH2, 2932 cm−1 of CH, and 1647 cm−1 of -CO) exhibited peaks confirmed the formation of CS-Ag NPs. Ag NPs-CS exhibited anticancer activity against Human lung adenocarcinoma cell lines (A549), the maximum cell death noticed at the concentration of 20 μg/mL and 70 μg/mL was 20 and 52 %, respectively. An aqueous Ag NPs-CS (100 μg/mL) was degraded ≥95 % of mixed dye target solution (25 mg/mL) containing equal volume of cationic dye (Methylene blue and Rhodamine B) and anionic dye (methyl orange). Therefore, these findings suggest that the shrimp shell waste derived CS can be used for the synthesis of CS-Ag NPs with potential biomedical and environmental applications.

Chitosan-capped silver nanoparticles with potent and selective intrinsic activity against the breast cancer cells

Graphical abstract

Chitosan capped silver nanoparticles: Adsorption and photochemical activities

Chitosan capped silver nanoparticles (Chi-Ag) were prepared using AgNO3 and sodium borohydride. Chitosan was detected by using ninhydrin test, thermal gravimetric analysis and measurement of relative viscosity. Chi-Ag was used for removal of cadmium (Cd2+) at room temperature. The maximum monolayer adsorption capacity, and sorption intensity were estimated to be 119.04 mg/g and 1.6, respectively, from Langmuir and Freundlich adsorption isotherm models. The kinetics of Cd2+ adsorption onto Chi-Ag was proceeds through the pseudo-second-order kinetic model. Boyd and Elovich models suggest the adsorption and/or coordination of Cd2+ with the NH2 and OH groups of chitosan along with AgNPs proceeds through the film diffusion and chemisorption process. The average viscosity molecular weight of chitosan and Chi-Ag decreased with increased potassium persulfate (K2S2O8) and hydrogen peroxide (H2O2) concentration. The presence of H2O2 and K2S2O8 promoted the hydrolysis of chitosan due to the cleavage of glycosidic bond by generated HO and SO4− radicals.

Doxorubicin Immobilization on chitosan-modified silver Nanoparticles as a drug delivery method for effective anticancer treatment

Objective: The goal of this research is to load Doxorubicin (DOX) on silver nanoparticles coupled with folic acid and test their anticancer properties against breast cancer.
 Methods: Chitosan-Capped silver nanoparticles (CS-AgNPs) were manufactured and loaded with folic acid as well as an anticancer drug, Doxorubicin, to form CS-AgNPs-DOX-FA conjugate. AFM, FTIR, and SEM techniques were used to characterize the samples. The produced multifunctional nano-formulation served as an intrinsic drug delivery system, allowing for effective loading and targeting of chemotherapeutics on the Breast cancer (AMJ 13) cell line. Flowcytometry was used to assess therapy efficacy by measuring apoptotic induction.
 Results: DOX and CS-AgNPs-DOX-FA were found to inhibit cell proliferation in the AMJ13 cell line, according to the findings. The anti-proliferative impact of these chemicals was attributed to cell death and activation of apoptosis, as evidenced by dual staining with acridine orange and Ethidium bromide. The presence of high fluorescent signals specific for cellular uptakes of CS-AgNPs-DOX-FA into the cell line's cytoplasm was confirmed.
 Conclusion: According to the findings of this study, CS-AgNPs-DOX-FA has a lot of promise to be used as an anticancer delivery system. The findings imply that this conjugate should be researched further for potential use as anticancer drug.

Chitosan-capped silver nanoparticles: fabrication, oxidative dissolution, sensing properties, and antimicrobial activity

Chitosan-capped silver nanoparticles: fabrication, oxidative dissolution, sensing properties, and antimicrobial activity

Spectrophotometric Determination of Naproxen Using Chitosan Capped Silver Nanoparticles in Pharmaceutical Formulation

In this work, determination of naproxen concentration by chitosan capped silver nanoparticles were investigated. A new, simple and inexpensive spectrophotometric method for the first time was developed. The characteristics of chitosan capped silver nanoparticles were determined by ultraviolet spectroscopy (UV), Fourier transform infrared spectroscopy (FT-IR), atomic force microscopy (AFM), dynamic light scattering (DLS) and zeta potential (ZP) under optimal conditions. It worth to be mentioned that, synthesized chitosan (CS) -Ag nanoparticles were approximately 100 nm and PDI 0.385 with strong anionic (-24.8mV) zeta potential in acidic condition. It was found that chitosan as a chiral selector was able to detect naproxen at optimal experimental conditions. Validation of this method, including limit of detection and limit of quantification were accurately confirmed according to ICH instructions. Based on this method, the limit of detection (LOD) and the limit of quantification (LOQ) of naproxen were calculated 0.022 and 0.066 mol. L-1, respectively. Analysis of statistical data, the reproducibility and accuracy of this method demonstrated that the use of this novel method is valuable and practical for determination of naproxen in pharmaceutical formulations

Topical delivery of chitosan-capped silver nanoparticles speeds up healing in burn wounds: A preclinical study

This study investigated the effects of topical application of chitosan-capped silver nanoparticles (Ch/AgNPs) on burn wound healing. The chitosan-capped silver nanoparticles were synthesized in one step from the silver nitrate, sodium borohydride, and chitosan and were characterized using transmission electron microscopy, fourier transform infrared spectroscopy, and X-ray diffraction methods. The antioxidant assay was performed to evaluate the scavenging rate. The effects of Ch/AgNPs on burn wound healing was also evaluated by histopathological, molecular, and biochemical evaluations after 7, 14 and 28 days of treatment in a rat model. In comparison to the negative control and silver sulfadiazine groups, the Ch/AgNPs treated wounds exhibited significantly lower inflammatory reaction as determined by the reduced level of interleukin-1β (IL-1β) and neutrophil counts. Treatment by Ch/AgNPs also significantly enhanced re-epithelialization, so that complete epithelialization was achieved in the lesions of the animals of this group, at the 7th day post-wounding. Rapid re-epithelialization, improved granulation tissue formation, reduced IL-1β expression, mild inflammation, and increased transforming growth factor-β1 and basic fibroblast growth factor, at 7 days post-wounding, are convincing reasons to confirm this idea that Ch/AgNPs are effective in speeding up the wound healing stages. Our histopathological findings are in agreement with the molecular and biochemical results and strongly demonstrate that Ch/AgNPs stimulate burn wound healing by decreasing the length of repair phases. Therefore, on the basis of our findings, Ch/AgNPs can be a promising candidate in stimulating wound repair and regeneration.

Thiol terminated chitosan capped silver nanoparticles for sensitive and selective detection of mercury (II) ions in water

In this paper, we report a simple method for the optical detection of environmentally toxic mercury (II) ions (Hg2+) in water using chitosan capped silver nanoparticles (Ch–Ag NPs). The yellow colored aqueous solution of Ch-Ag NPs instantly (10 s) became colorless with addition of Hg2+ ions. Cu2+, and Fe3+ ions also produced colorless solution after 1 min. To overcome the Cu2+ and Fe3+ interference, thiol terminated chitosan was synthesized via amide coupling formation between amine group of chitosan and carboxylic acid group of 3-Mercaptopropanoic acid (3-MPA). The detailed study of selectivity, sensitivity, effect of interfering radicals, and response time confirmed that thiol terminated chitosan capped silver nanoparticles (Mod-Ch-Ag NPs) are highly selective and speedy for Hg2+ ions detection. The limit of detection was found to be 5 ppb. Furthermore, since the change in color with addition of mercury can be observed by naked eye, the developed nanosensor can also be utilized for real field applications. Hydrogel of Mod-Ch–Ag NPs was successfully synthesized and it was also found highly specific for Hg2+ ions. It was observed that separation of Hg2+ ions is also possible by simply changing the pH of the solution containing colorless Hg2+ with Mod-Ch-Ag NPs.

Green synthesis of chitosan capped silver nanoparticles and their antimicrobial activity

Chitosan is a polymeric compound with functional groups which enable surface binding to nanoparticles and antibacterial activity. The antimicrobial activity was studied using silver nanoparticles with varied concentrations of chitosan. The nanoparticles were synthesized through a simple and environmentally friendly method at room temperature. Spherical particles with average sizes between 2 and 6 nm were obtained and their crystallinity showed a face-centered cubic phase. The evidence of chitosan presence on the nanoparticle surface was confirmed by the characteristic diffraction peak of chitosan and by FTIR spectra where the bonding of amine group could be depicted. The chitosan-capped silver nanoparticles showed good antibacterial and antifungal activities with MIC values between 0.20 and 1.5 mg.mL-1 compared to those obtained from most of references (up to 6.25 mg.mL-1) on the selected gram-positive (Staphylococcus aureus, Enterococcus faecalis), gram-negative (Klebsiella pneumoniae, Pseudomonas aeruginosa ) bacteria and fungi (Candida albicans, Cryptococcus neoformans).

Chiral recognition of tryptophan enantiomers using chitosan-capped silver nanoparticles: Scanometry and spectrophotometry approaches

A new, fast and inexpensive colorimetric sensor was developed for chiral recognition of tryptophan enantiomers using chitosan-capped silver nanoparticles. The function of the sensor was based on scanometry and spectrophotometry of the colored product of a reaction solution containing a mixture of chitosan-capped silver nanoparticles, phosphate buffer and tryptophan enantiomers. The image of the colored solution was taken using the scanometer and the corresponding color values were obtained using Photoshop software which subsequently were used for optimization of the experimental parameters as the analytical signal. Two types of color values system were investigated: RGB (red, green and blue values) and CMYK (cyan, magenta, yellow and black values). The color values indicated that L-tryptophan had better interaction than D-tryptophan with chitosan-capped silver nanoparticles. A linear relationship between the analytical signal and the concentration of L-tryptophan was obtained in the concentration range of 1.3 × 10−5–4.6 × 10−4molL−1. Detection limits, were obtained to be 2.1 × 10−6, 2.4 × 10−6 and 3.8 × 10−6molL−1 for L-tryptophan based on R (red), G (green) and B (blue) values, respectively.

Colorimetric detection of biothiols based on aggregation of chitosan-stabilized silver nanoparticles

We have described a simple and reliable colorimetric method for the sensing of biothiols such as cysteine, homocysteine, and glutathione in biological samples. The selective binding of chitosan capped silver nanoparticles to biothiols induced aggregation of the chitosan–Ag NPs. But the other amino acids that do not have thiol group cannot aggregate the chitosan–Ag NPs. Aggregation of chitosan–Ag NPs has been confirmed with UV–vis absorption spectra, zeta potential and transmission electron microscopy images. Under optimum conditions, good linear relationships existed between the absorption ratios (at A500/A415) and the concentrations of cysteine, homocysteine, and glutathione in the range of 0.1–10.0μM with detection limits of 15.0, 84.6 and 40.0nM, respectively. This probe was successfully applied to detect these biothiols in biological samples (urine and plasma).

Trimethyl chitosan-capped silver nanoparticles with positive surface charge: Their catalytic activity and antibacterial spectrum including multidrug-resistant strains of Acinetobacter baumannii

We report a facile route for the green synthesis of trimethyl chitosan nitrate-capped silver nanoparticles (TMCN-AgNPs) with positive surface charge. In this synthesis, silver nitrate, glucose, and trimethyl chitosan nitrate (TMCN) were used as silver precursor, reducing agent, and stabilizer, respectively. The reaction was carried out in a stirred basic aqueous medium at room temperature without the use of energy-consuming or expensive equipment. We investigated the effects of the concentrations of NaOH, glucose, and TMCN on the particle size, zeta potential, and formation yield. The AgNPs were characterized by UV–vis spectroscopy, photon correlation spectroscopy, laser Doppler anemometry, transmission electron microscopy, X-ray diffraction, and X-ray photoelectron spectroscopy. The catalytic activity of the TMCN-AgNPs was studied by the reduction of 4-nitrophenol using NaBH4 as a reducing agent. We evaluated the antibacterial effects of the TMCN-AgNPs on Acinetobacter baumannii, Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus using the broth microdilution method. The results showed that both gram-positive and gram-negative bacteria were killed by the TMCN-AgNPs at very low concentration (<6.13μg/mL). Moreover, the TMCN-AgNPs also showed high antibacterial activity against clinically isolated multidrug-resistant A. baumannii strains, and the minimum inhibitory concentration (MIC) was ≤12.25μg/mL.

Differential Delivery of Vincristine to A549 Cells Using Chitosan Capped Silver Nanoparticles Under the pH Trigger

Differential Delivery of Vincristine to A549 Cells Using Chitosan Capped Silver Nanoparticles Under the pH Trigger

Preparation of a silver nanoparticle-based dual-functional sensor using a complexation-reduction method.

A dual-functional sensor based on silver nanoparticles was synthesized by a two-stage procedure consisting of a low-temperature chitosan-Ag(+) complexation followed by a high-temperature reduction of the complex to form chitosan-capped silver nanoparticles (CS-capped Ag NPs). The surface plasmon resonance (SPR) absorption and fluorescence emission of the silver nanoparticles were influenced by the concentration and degradation time of chitosan, and the temperatures of the complexation and reduction reactions. The SPR absorption band was blue-shifted while the intensities of emission and absorption were decreased after reacting the silver nanoparticles with Hg(2+) ions. The silver nanoparticles reacted with Hg(2+) were characterized by high resolution transmission electron microscopy (HRTEM), energy dispersive spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), and surface-enhanced Raman scattering spectroscopy (SERS). The results suggested that the particle growth and aggregation of the silver nanoparticles were caused by the adsorption of Hg(2+) and deposition of Hg(0) on the nanoparticle surface. Direct correlations of the SPR absorption and fluorescence emission with the concentration of Hg(2+) were useful for quantitative analysis of Hg(2+). It was possible to use the dual-functional silver nanoparticles as a colorimetric and fluorescent sensor for sensitive and selective detection of Hg(2+) ions.

Antimicrobial activity of UV-induced chitosan capped silver nanoparticles

This study presents a green method to synthesize antibacterial silver nanoparticles (Ag NPs) employing chitosan and silver nitrate. Chitosan acted as dispersion and stabilizing agent. Ag NPs were radiated by UV ray to improve their reaction efficiency. UV–vis spectra showed that absorption peak of Ag NPs occurred at 402nm wavelength. TEM observed that the average size of Ag NPs was 25–30nm. XRD revealed that crystalline peak was Ag (111), Ag (200) and Ag (220). The synthesized Ag NPs had antibacterial activity against Escherichia coli.

Biopolymer capped silver nanoparticles as fluorophore for ultrasensitive and selective determination of malathion

This paper describes a novel luminescent sensor for malathion using chitosan capped silver nanoparticles (Chi-AgNPs) as fluorophore. The Chi-AgNPs were synthesized by the wet-chemical method and were characterized by absorption, fluorescence, HR-TEM, XRD and DLS techniques. The Chi-AgNPs show the absorption maximum at 394nm and emission maximum at 536nm. While adding 10µM malathion, yellow color Chi-AgNPs was changed to brown and the absorbance was decreased along with a redshift. The observed spectral and color changes were mainly due to the aggregation of Chi-AgNPs. This was confirmed by zeta potential, DLS and HR-TEM studies. No significant absorption spectral change was observed for Chi-AgNPs in the presence of less than micromolar concentrations of malathion. However, the emission intensity of Chi-AgNPs was decreased and the emission maximum was shifted toward higher wavelength in the presence of picomolar concentration of malathion. Based on the decrease in emission intensity, the concentration of malathion was determined. The Stern–Volmer constant, Gibbs free energy change, association constant, quantum yield and binding constant were calculated and the quenching mechanism was proposed. The Chi-AgNPs show good selectivity toward the determination of 10nM malathion in the presence of 1000-fold higher concentrations of common interferents. A good linearity was observed for the emission intensity against 1×10−9–10×10−12M malathion and the detection limit was found to be 94fML−1 (S/N=3). The proposed method was successfully applied to determine malathion in fruits and water samples and the obtained results were validated with HPLC.

Chitosan capped Silver nanoparticles used as Pressure sensors

Chitosan capped Silver nanoparticles used as Pressure sensors

Chitosan-capped silver nanoparticles as a highly selective colorimetric probe for visual detection of aromatic ortho-trihydroxy phenols

We reported a new application of silver nanoparticles (NPs) for the visual sensing of aromatic polyphenols, such as gallic acid, pyrogallol and tannic acid, which is based on the intensified plasmon absorbance signals and visual changes from yellow to orange due to hydrogen-bonding recognition and subsequent catalytic oxidation of the target phenols by chitosan-capped AgNPs (Ch-AgNPs). The Ch-AgNPs are generated by the well-known reaction of AgNO3 with NaBH4 and stabilized with chitosan which is a polysaccharide biopolymer with excellent dispersive properties and stability in aqueous media. After optimizing some experimental conditions, a very simple and facile sensing system has been developed for the detection of gallic acid, pyrogallol and tannic acid in water samples. The proposed system promises high selectivity toward gallic acid, pyrogallol and tannic acid, and other phenolic compounds including p-aminobenzoic acid, pentachlorophenol, 2,4,6-trinitrophenol, 2,4-dinitrophenol, p-nitrophenol, 1-naphthol, β-naphthol, p-aminophenol, catechol, hydroquinone, m-dihydroxybenzene, phloroglucin and phenol could not induce a color change even at 0.1 mM. The outstanding selectivity property of the proposed method for gallic acid, pyrogallol and tannic acid resulted from the Ch-AgNPs-mediated reduction of Ag(+) by the target phenols. Also, a wide linear response range was obtained for the three targets. The linear response ranges for gallic acid, pyrogallol, and tannic acid were from 1 × 10(-5) to 1 × 10(-3) M, 1 × 10(-5) to 1 × 10(-2) M and 1 × 10(-6) to 1 × 10(-4) M with a respective detection limit (DL) of 1 × 10(-5), 1 × 10(-5), and 1 × 10(-6) M. The proposed method was successfully applied to detect target phenols in environmental water samples. Furthermore, because the color change from yellow to orange is observable by the naked eye, it is easy to realize visual detection of the target phenols without any instrumentation or complicated design. The experimental results reported here open up an innovative application of the catalytic reactivity of AgNPs.