Optical Nonlinear Properties of Gold Nanoparticles Synthesized by Laser Ablation in Polymer Solution

In the present study, gold nanoparticles were synthesized in various polymer solutions by means of employing laser ablation technique at the same ablation time. Specifically, gold nanoparticles were synthesized in polyethylene glycol and chitosan solutions, in order to compare the effects of the liquid media which served as stabilizers for particle size and volume fraction of nanoparticles. In addition, this experiment was repeated in distilled water for reference purposes. As the findings indicated, the particle size which was obtained in polyethylene glycol was about 7.49 nm, that is, smaller than those of chitosan solution and distilled water, respectively. In contrast, it was observed that the volume fraction of gold nanoparticles increased in polyethylene glycol in comparison with the other media which indicated an effect on the formation of NPs. On the other hand, Z-scan technique was employed to measure the nonlinear refractive index and nonlinear absorption coefficient of nanofluids containing gold nanoparticles. Consequently, the nonlinear properties of nanofluids pointed to a significant contribution with the number of nanoparticles observed in fluids and both optical nonlinear parameters were observed to increase by means of a prior increase in the volume fraction of Au-NPs in polyethylene glycol solution

Synthesis of Silver Nanoparticles Dispersed in Various Aqueous Media Using Laser Ablation

The particle size, morphology, and stability of Ag-NPs were investigated in the present study. A Q-Switched Nd: YAG pulsed laser (λ = 532 nm, 360 mJ/pulse) was used for ablation of a pure Ag plate for 30 min to prepare Ag-NPs in the organic compound such as ethylene glycol (EG) and biopolymer such as chitosan. The media (EG, chitosan) permitted the making of NPs with well dispersed and average size of Ag-NPs in EG is about 22 nm and in chitosan is about 10 nm in spherical form. Particle size, morphology, and stability of NPs were compared with distilled water as a reference. The stability of the samples was studied by measuring UV-visible absorption spectra of samples after one month. The result indicated that the formation efficiency of NPs in chitosan was higher than other media and NPs in chitosan solution were more stable than other media during one month storage. This method for synthesis of silver NPs could be as a green method due to its environmentally friendly nature

Bimetallic nanoparticles for biomedical applications: a review

Bimetallic nanoparticles, or BMNPs, are nanosized structures that are of growing interest in biomedical applications. Although their production shares aspects with physicochemical approaches for the synthesis of their monometallic counterparts, they can show a large variety of new properties and applications as a consequence of the synergetic effect between the two components. These applications can be as diverse as antibacterial treatments or anticancer or biological imaging approaches, as well as drug delivery. Nevertheless, utilization of BMNPs in such fields has received limited attention because of the severe lack of knowledge and concerns regarding the use of other nanomaterials, such as stability and biodegradability over time, tendency to form clusters, chemical reactivity, and biocompatibility. In this review, a close look at bimetallic systems is presented, focusing on their biomedical applications as antibacterial, anticancer, drug delivery, and imaging agents, showing significant enhancement of their features compared to their monometallic counterparts and other current used nanomaterials for biomedical applications.Peer reviewe