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Purpose We tend to evaluated a method for loading 6Mercaptopurine (6MP) on green synthesized hybrid chitosan gold nanoparticles (AuNPs) forming 6MP-AuNPs nanocomposite for the first time in combinatorial chemo-photothermal therapy. Methods The AuNPs were synthesized using chitosan as a reducing and capping agent. Different concentrations of 6MP were mixed AuNPs. Cells were incubated with 6MP and 6MP loaded AuNPs for 48 h and then exposed to laser. Results AuNPs and 6MP-AuNPs nanocomposite have small sizes of 18 ± 4 and 25 ± 5 nm and exhibit high stability with Zeta potential of 55.9 ± 6.3 and 57 ± 4 mV. 6MP-AuNPs nanocomposite irradiated with Diode Pumped Solid State (DPSS) laser showed a maximum inhibition in cell viability reaching 63% at 1.25 µM. Conclusions A hybrid chitosan gold nanoparticle is a powerful anti-cancer drug carrier as well as photothermal agent in combinatorial chemo-photothermal therapy.

Early cancer diagnosis through characterizing light propagation and nanotechnology increases the survival rate. The present research is aimed at evaluating the consequence of using natural nanoparticles in cancer therapy and diagnosis. Colon cancer cells were differentiated from the normal cells via investigating light diffusion combined with the fluorescence effect of the Ashwagandha chitosan nanoparticles (Ash C NPs). Ionic gelation technique synthesized the Ash C NPs. High-resolution transmission electron microscope, dynamic light scattering, and zeta potential characterized Ash C NPs. Fourier transform infrared spectroscopy analyzed Ash C NPs, chitosan, and Ashwagandha root water extract. Moreover, the MTT assay evaluated the cytotoxicity of Ash C NPs under the action of near-infrared light (NIR) irradiation. The MTT assay outcomes were statistically analyzed by Bonferroni post hoc multiple two-group comparisons using one-way variance analysis (ANOVA). Based on the Monte-Carlo simulation technique, the spatially resolved steady-state diffusely reflected light from the cancerous and healthy cells is acquired. The diffuse equation reconstructed the optical fluence rate using the finite element technique. The fluorescent effect of the nanoparticles was observed when the cells were irradiated with NIR. The MTT assay revealed a decrease in the cell viability under the action of Ash C NPs with and without laser irradiation. Colon cancer and normal cells were differentiated based on the optical characterization after laser irradiation. The light diffusion equation was successfully resolved for the fluence rate on cells’ surfaces showing different normal and cancer cells values. Ash C NPs appeared its fluorescent effect in the presence of NIR laser.

The aim of the presented work is introducing a simple and rapid way with high profit not only to reduce expenses and efforts, but also to guarantee safety and eco-friendly biogas source. Thus, the effect of nanoferrites, as a source of metal ion, on biogas production rate was studied. Nanoferrites MFe2O4 (M = Fe, Ni, Co) were synthesized via a modified aqueous co-precipitation method under alkaline conditions using monoisopropanolamine (MIPA) as a base and capping agent. The prepared nanoparticles were investigated by transmission electron microscopy (TEM), X-ray diffractometry (XRD), and vibrating sample magnetometer (VSM). Anaerobic system was constructed from special bench-scale digesters for examination of the nanoferrite effect on biogas production rate. The TEM images showed ultra-small, spherically, slightly aggregated, and well-distributed nanoparticles in the range of 5.7, 4.9, and 3.5 nm for magnetite (Fe3O4), cobalt ferrite (CoFe2O4), and nickel ferrite (NiFe2O4) nanoparticles (NPs), respectively. XRD patterns confirmed the cubic spinel structure for the prepared nanoparticles. VSM measurements predicted the superparamagnetic behaviors for all prepared nanoparticles. The effects of Fe3O4, CoFe2O4, and NiFe2O4 NPs with same concentrations on biogas production were investigated and yielded biogas cumulative volumes of 210.8%, 220.5%, and 171.9%, respectively, with respect to control, after 50 days of incubation. CoFe2O4 nanoparticles showed the greatest enhanced effect on the cumulative biogas production, followed by Fe3O4 nanoparticles.

In the present work, nanoparticle-enhanced laser-induced breakdown spectroscopy was used to analyze an aluminum alloy. Although LIBS has numerous advantages, it suffers from low sensitivity and low detection limits compared to other spectrochemical analytical methods. However, using gold nanoparticles helps to overcome such drawbacks and enhances the LIBS sensitivity in analyzing aluminum alloy in the current work. Aluminum was the major element in the analyzed samples (99.9%), while magnesium (Mg) was the minor element (0.1%). The spread of gold nanoparticles onto the Al alloy and using a laser with different pulse energies were exploited to enhance the Al alloy spectral lines. The results showed that Au NPs successfully improved the alloy spectral lines intensity by eight times, which could be useful for detecting many trace elements in higher matrix alloys. Under the assumption of local thermodynamic equilibrium, the Boltzmann plot was used to calculate the plasma temperature. Besides, the electron density was calculated using Mg and H lines at Mg(I) at 285.2 nm and Hα(I) at 656.2 nm, respectively. Three-dimensional contour mapping and color fill images contributed to understanding the behavior of the involved effects.

Nanomedicine and fluorescent optical imaging are effective in early cancer detection. The current study synthesized biocompatible nanocomposites from natural biomaterials towards inexpensive and safe cancer theragnostic. Two forms of nanocomposites were synthesized using the ionic gelation method: 1. Chitosan/ Withania Somnifera /tripolyphosphate nanocomposites, 2. Withania Somnifera/Chitosan nanocomposites. The nanocomposites were characterized by dynamic light scattering, zeta potential, and the transmission electron microscope. Fourier transform infrared spectroscopy analyzed the Withania Somnifera root water extract, Chitosan, and the synthesized nanocomposites. The cytotoxicity of the nanocomposites was investigated against the colon cancer cells (Caco2 cells) in the absence and the presence of laser (665 nm, 5 mW) irradiation. MTT assay evaluated the cytotoxicity, and Trypan blue assay assessed the cell viability. Cancerous cells were photographed under the inverted microscope in the presence and the absence of laser irradiation. Results were analyzed statistically using one-way variance (ANOVA) analysis with Bonferroni post-Hoc multiple two-group comparisons. The characterization results ensured the successful synthesis of Withania Somnifera/Chitosan nanocomposites. The results showed an increase in the cytotoxicity against colon carcinoma and a decrease in cell viability in the presence and absence of Near-infrared laser irradiation under the action of nanocomposites. The cytotoxicity of the synthesized nanocomposites increased by exposing the cells to the laser. The shining light of the nanocomposites appeared on the cells photographed under the inverted microscope. The synthesized natural nanocomposites promise systemic cytotoxicity will be efficient in molecular imaging in vivo applications.

Traditional fluorophores for fluorescence medical imaging are associated with downconversion phenomenon upon ultraviolet stimulation and lead to many obstacles. Nevertheless, a recent categorization of inorganic fluorescent nano-particle was produced in order to prevent these limitations such as: the upconversion nano-particles (UCNPs). So that, our results suggested that: Photosensitizer (PSs) for example chlorophyll types are the best used because they come from natural sources and have a several features better than other Ps. On the other hand, the potential toxicity and biocompatibility of UCNPs are in connection with their biomedical methodologies. Bear in mind that, UCNPs cannot be rapidly involved in biological environment. Above all, work out the good manners of UCNPs in biological systems as well as overcome toxicity to pave the way to utilize this type of nano-particles in medical methodologies recently.

In our present work gold nanoparticles were successfully prepared using chitosan as reducing and capping agent and subsequently used as carriers for hydrophobic anticancer 6 mercaptopurine (6MP). The use of this drug is limited due to its poor bioavailability. The purpose of the present investigation was to evaluate a method for loading hydrophobic drug 6MP on chitosan reduced gold nanoparticles (AuNPs).The resulting AuNPs and 6MP loaded AuNPs were characterized by ultraviolet visible spectrophotometry, transmission electron microscopy. To estimate the improvement of the drug delivery of AuNPs, breast cancer cells MCF7 were treated with 6MP and 6MP loaded AuNPs and cell viability was studied in vitro using Sulphorhodamine-B (SRB) assay. The data showed, both free 6MP and 6MP loaded AuNPs revealed anti-proliferation activity against the cancer cells in dose-dependent manners. Moreover, 6MP loaded AuNPs displays significantly greater anti-proliferation activity than that of free 6MP at all concentrations and IC50 1.93nM. The improvement of anti-proliferation activity of 6MP loaded AuNPs compared to that of 6MP can be attributed to enhanced intracellular uptake of the functionalized GNPs via the mechanism of endocytosis

A green method was used for producing gold nanoparticles (Au NPs) using chitosan as a natural cationic, biodegradable and biocompatible polymer. In this method, chitosan acts as a reducing and stabilizing agent for the synthesis of Au NPs. Different concentrations of chitosan solutions (0.01%, 0.05%, 0.1%, 0.2%, 0.5% and 1%) were applied. In an attempt to mitigate the side effects of anti-cancer drug, 5-fluorouracil (5-FU), through reducing drug doses in photothermal therapy, the formed positively-charged chitosan-wrapped Au NPs were used as a drug delivery system for negatively charged 5-FU to hepatocellular carcinoma cells (HepG2). Au NPs as well as 5-FU@Au nanocomposites were characterized with UV-VIS spectroscopy, particle size, zeta potential, Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM) and High-Performance Liquid Chromatography (HPLC). The chitosan concentration was shown to be an important parameter for optimizing the dispersion of Au NPs and 5-FU@Au nanocomposites over long time. This stability offers the 5-FU@Au nanocomposites as good candidate for cancer treatment with reduced drug doses in photothermal therapy. A 72% loading-efficiency of 5-FU was obtained. Cytotoxic assay was carried out on HepG2 cell line and it reveals the effectiveness of 5-FU@Au nanocomposites in the presence and absence of laser irradiation compared with the free 5-FU. The cytotoxicity effect of free 5-FU and 5-FU@AuNPs nanocomposites was studied, and it was found that the concentration of 5-FU@Au nanocomposites required to attain 50% of inhibition growth rate was lower than that of free 5-FU in absence of laser radiation and was much lower in presence of laser radiation.

Photothermal nanomaterials with near-infrared absorption and high energy conversion efficiency have recently attracted significant interest. Polypyrrole-gold nanocomposites (PPy-Au NCs) as photothermal nanoagents are synthesized using ex-situ polymerization method of the modified pyrrole monomers. Microscopic and spectroscopic characterization techniques are used to reveal the surface structure, composition variation and photoelectric properties of PPy-Au NCs, gold nanorods (Au NRs) and polypyyrole nanoparticles (PPy NPs). Their cytotoxic effects on the viability of Ehrlich Ascites Carcinoma cells in the dark are demonstrated. The surface coating of Au NRs with PPy NPs shows an enhancement in the photothermal efficiency of the proposed photothermal nanoagent. The photothermal conversion of nanomaterials are examined using polarized polychromatic incoherent low-energy light source (the energy density of the light is 2.4 J/cm2 per minute and the specific power density is 40 mW/cm2).

A new ascorbic acid (AA) nanocomposite with low toxicity and high photo and thermal stability is constructed for certain dermatological applications in humans. The presented nanocomposite consists of AA, nano-hydroxyapatite (nHAp) and carboxymethyl cellulose (CMC). The physicochemical properties of such CMC-nHAp-AA nanocomposite were characterized using X-Ray diffractometery (XRD), Fourier Transform Infra-Red (FTIR), Energy Dispersive X-ray (EDX) and UV–VIS spectroscopies. The size and morphology of the synthesized nanocomposites were characterized by TEM/SEM techniques. A detailed photo and thermal stability studies were performed to examine the stability of AA in the proposed nanocomposite. The AA content showed great stability against sunlight up to 3 h or more and against heat up to 100 °C, whereas it showed relatively limited stability against laser light up to 10 min depending on the laser type. Cytotoxicity endpoints, evaluating the cell viability and IC50 (50% inhibitory concentration) have been performed for the exposed synthesized nanocomposite. There wasn't any effect on the cell viability up to 50 μg/mL of CMC-nHAp-AA nanocomposite. Based on IC50 values, it has been found that after 24 h of observation the IC50 of CMC-nHAp-AA nanocomposite was 0.199 μg/mL which depicts high safety profile of the proposed nanocomposite. The produced nanocomposite (CMC-nHAp-AA) is expected to possess great potential in dermatological applications due to its high stability and increased proliferative capacity which lasts longer than AA alone.

Increasing the limit of dispersion of metal-free phthalocyanine (H2Pc) in an aqueous medium using biosynthetic gold nanoparticles for photodynamic therapy (PDT) is investigated. Gold nanoparticles (Au NPs) are biosynthesized in one step using Potatoes (Solanum tuberosum) extract and are characterized by UV/VIS spectrophotometry, Fourier transformer infrared spectroscopy (FTIR), and transmission electron microscopy (TEM). The metal-free phthalocyanine is conjugated to the surface of the gold nanoparticles in a side to side regime through the secondary amine groups of H2Pc. The clear violet solution of phthalocyanine-gold (Pc-Au) nanoconjugates is investigated by UV–VIS, FTIR and TEM techniques. Disappearance of the absorption band of the secondary amine in the Pc-Au nanoconjugates compared to that of the parent H2Pc, and detection of the absorption band of H2Pc in the aqueous medium confirmed the dispersion of H2Pc and consequently the loading of H2Pc on the surface of Au NPs. The cytotoxic effect of biosynthetic gold nanoparticles and Pc-Au nanoconjugates compared to chemically synthesized gold nanoparticles on buffalo epithelial cells has been studied in vitro. Interestingly, the results showed that the biosynthetic Au NPs as well as Pc-Au nanoconjugates have no effect on buffalo epithelial cells viability, which indicating their biocompatibility contrary to the chemically synthesized Au NPs. This work will open the door, for the first time, for using H2Pc suspended in water for PDT and other phototherapeutic applications.

Aim: There is an urgent need to develop alternative antimicrobial agents and, one of which is via the use of nanotechnology. Green synthetic routes are recently being replaced for nanoparticles preparation. Methods results: Silver–curcumin nanoconjugates (Ag–CurNCs) were prepared in an eco-friendly method. The prepared nanomaterials were characterized and the photostability was studied under the influence of UV irradiation. Results showed that, the conjugation between curcumin and silver in the nanoform improve the photostability of curcumin. Cytotoxicity was studied on different skin cell lines, and antibacterial activity was investigated against Escherichia coli. Results revealed the antibacterial activity of the prepared nanoconjugates (Ag–CurNCs) with minimal toxicity to skin cells. Conclusion: Silver nanoparticles improve the photostability and antibacterial activity of curcumin, while curcumin helps in preparing biocompatible silver nanoparticles.

In this study, three types of nanocomposites (Chitosan –TPP nanoparticles (C-TPP NPs), Chitosan-Ashwagandha nanoparticles (Ash-C NPs), and chitosan-Ashwagandha-TPP nanoparticles (C-Ash–TPP NPs)) were synthesized for targeting cancer colon (Caco-2) cell line. Fourier transform infrared spectroscopy (FTIR) analysis was applied to get the IR bands of the functional groups for each of Ashwagandha root water extract (ASH R WEX), Chitosan (c), and the numerous synthesized nanocomposites. Nanoparticles (NPs) were characterized by using Dynamic Light Scattering (DLS), Zeta Potential (ZP) and Transmission Electron Microscope (TEM). Two Groups of cancer therapy were applied to Caco-2 cells. In the first Group, the effectiveness of the synthesized NPs was observed without laser irradiation. the second Group, the effectiveness of the synthesized NPs was observed in the case of laser irradiation (660 nm diode laser, 5 min). On the other hand, the cell viability for Caco-2 cells exposed to low-level laser therapy was observed. The Cytotoxicity was analyzed by MTT assay and the cell viability was examined by the trypan blue method. The MTT assay showed increased cytotoxicity for each group of the treatment. Also, the results showed that the synthesized nanocomposites caused a decrease in cell viability in the two treatment groups and, in the case of laser irradiation lonely.

Copper sulfide nanocrystals (Cu2–xS NCs) consisting of earth-abundant and nontoxic elements have attracted attention for optoelectronic and plasmonic applications due to their tunable light absorption and emission properties. In this work, we present a study of the electronic changes induced in organic-capped Cu2–xS NCs by surface modification treatments using charge transport and optical spectroscopy measurements. We have investigated surface treatments yielding ligand exchange and also ligand removal as well as changes in electronic defect density. The structural and morphological changes induced by the treatments were monitored by infrared spectroscopy, electron microscopy, and electron paramagnetic resonance. Untreated Cu2–xS NCs exhibit a strong absorption band arising from a localized surface plasmon resonance (LSPR). We found that using a ligand exchange procedure (ethanedithiol treatment), the electrical conductivity in films of Cu2–xS NCs can be enhanced by 5 orders of magnitude, while maintainin...

Medical diagnosis using optical techniques and contrast agents is a promising method where it is safe and unexpansive technique. Every tissue can be distinguished by its optical absorption and scattering properties that are related to many physiological changes and it is a sign for cancerous cells. Characterizing the light propagation in the human tissues is a vital issue in early cancer diagnosis for more effective therapeutic. In this work, the glowing effect of chitosan nanoparticles has been observed. Also, the light propagation in each of colon cancer (Caco-2 cell line) and normal cells (WI-38 cell line) at 650 nm and 808 nm in the absence and in the presence of chitosan nanoparticles was studied to study its effect in differentiate the cancer cells from the normal cells. Chitosan nanoparticles were characterized by the dynamic light scattering and transmission electronic Microscope (TEM). A Monte-Carlo simulation model was applied to obtain spatially resolved steady state diffuse reflectance measurements for each of the examined cells. Furthermore, the optical fluence rate distribution at the tissue surface were used to reconstruct the image using the diffuse equation using the finite element method. Chitosan nanoparticles appeared its glowing effect. The proposed diffuse reflectance curves and fluence rate images show different features regarding for each of Caco-2 cell line and WI-38 cell line that promises to be effective in medical diagnosis.

PbSe nanocrystals have been synthesized by conventional hot injection process and also using microwave technique. For PbSe nanocrystals obtained via hot injection process at 160 °C, the quality of the interface between the isolated and purified nanocrystals, after removal of capping ligands, strongly depends on the structure and stoichiometry of the surface. High resolution transmission electron microscopy has been used to investigate the interface between size selected PbSe nanocrystals. Oriented attachment of nanocrystals is achieved by protonation of oleate capping ligands using wet methanol and subsequent solvent evaporation. The removal of oleate from the surface is monitored using infrared spectroscopy. The attachment between preformed PbSe NCs has taken place exclusively through the {100} facets of the rock-salt lattice. In contrast to other related observations, it is found that nanocrystals can also attach through adjacent {100} facets. We have also studied the shape evolution of cubic PbSe NCs during microwave synthesis using transmission electron microscopy. The formation of PbSe nanocubes is attributed to the higher growth rate in the {111} direction compared to that in the {100} direction.

Nonhydrolytic/non-sol-gel pyrolytic synthesis technique, as a convenient method, was applied to synthesize zirconium oxide nanoparticles (ZrO2 NPs). Pyrolysis of either the mononuclear keto ester/alkoxide complex zirconium bis(isopropoxide)bis(tert-butylacetoacetate) [Zr(OiPr)2(tbaoac)2] (I) or the oligonuclear oxocluster compound [Zr6(OH)4O4(OMc)12] (II, Mc = methacrylate) generated ZrO2 NPs at moderate conditions of 300-400 °C. Trioctylamine, stearic acid, and/or oleic acid, which act as both solvents and stabilizing agents, were used. Under the adopted process conditions, the stabilizing agent oleic acid plays a vital role in determining the phase of as-synthesized colloidal ZrO2 nanoparticles, which yield the high-temperature tetragonal phase at moderate conditions of 335 °C. Those as-synthesized samples that contained both monoclinic and tetragonal ZrO2 phases (depending on the choice of the surfactant) were transformed into pure tetragonal phase at 1000 °C. An unambiguous phase determination of ZrO2 nanoparticles was carried out by the combination of powder X-ray diffraction (XRD) and Raman spectroscopy. Furthermore, the samples were analyzed by transmission electron microscopy (TEM), ultraviolet-visible (UV-vis) and photoluminescence (PL) spectroscopy, dynamic light scattering (DLS), and Fourier transform infrared (FT-IR) spectroscopy to elucidate the structure, chemical composition, and morphology of the obtained nanoparticles. Also, the phase transformations of the as-synthesized ZrO2 nanoparticles upon annealing were followed via Raman spectroscopy.

Nanoscale copper was selectively photodeposited onto the surface of hexadecylamine (HDA) stabilized (monodispersed not agglomerated) ZnO nanoparticles (NPs) of a diameter of 2–5 nm, which leads to HDA-stabilized Cu/ZnO NPs of varied Cu loading. The particles are soluble in non-polar organic solvents. The line broadening and the red shift of the surface plasmon band of Cu/ZnO NPs relative to HDA-stabilized Cu NPs, the profound decrease of the Cu/ZnO NPs visible photoluminescence at 525 nm, the increase of the UV emission intensity at 365 nm and the enhancement of the Raman scattering (RS) intensity in comparison to the parent ZnO NPs confirmed the interfacial contact between the Cu and ZnO phase.

Stearate@Cu/ZnO nanocomposite particles with molar ratios of ZnO ∶ Cu = 2 and 5 are synthesized by reduction of the metal-organic Cu precursor [Cu{(OCH(CH(3))CH(2)N(CH(3))(2))}(2)] in the presence of stearate@ZnO nanoparticles. In the case of ZnO ∶ Cu = 5, high-angle annular dark field-scanning transmission electron microscopy (HAADF-STEM) combined with electron-energy-loss-spectroscopy (EELS) as well as attenuated total reflection Fourier transform infrared (ATR-IR) spectroscopy are used to localize the small amount of Cu deposited on the surface of 3-5 nm sized stearate@ZnO particles. For ZnO ∶ Cu = 2, the microstructure of the nanocomposites after catalytic activity testing is characterized by HAADF-STEM techniques. This reveals the construction of large Cu nanoparticles (20-50 nm) decorated by small ZnO nanoparticles (3-5 nm). The catalytic activity of both composites for the synthesis of methanol from syn gas is evaluated.