Pulsed laser ablation synthesis of silver nanoparticles with rapid ionophore derivatives for antivirus activities.

68 Figure 4.9 Shows test A: Diagram (A) shows prepared sample E removed for 25 minutes and. B) shows the UV-VIS absorption spectra of AgNPs (sample E), synthesized using the 1064 nm and 532 nm wavelength pulse. 81 Figure 4.19 (A) shows UV-VIS absorption spectroscopy of synthesized doxycycline-AgNPs (B) Image of silver-doxycycline complex produced in sample E1B solution.

Background

In this study, we report silver nanoparticles (AgNPs) produced by solution laser ablation synthesis and discuss the main features of this approach. Laser ablation synthesis is one of the best techniques used to develop nanoparticles with consistent morphology that can be used for various medical applications.

Justification

Silver nanoparticles

In vitro laboratory tests have also provided clues to further support the inhibition of enzymes and other proteins. Positive silver ions (Ag+) are expected to show high affinity to the soft base-like thiolate ligands mostly found in bacterial membrane and subcellular structure (for example: sulfur-containing proteins and enzymes), causing inhibition of crucial biological cellular functions.

Anti-viral properties

Other well-established mechanisms using silver nanoparticles are silver-amino acid and silver-thiolate group interactions that take place on the proteins and DNA.

Ionophores

Coupled silver ionophores

The mechanism of action of these drugs against Plasmodium parasites is believed to be partly related to its interaction with DNA and inhibition of the polymerization of its proteins. Do-AgNPs use the mechanism of disruption of tRNA binding (ribonucleic acid transfer) by blocking the adhesion of aminoacyl-t-RNA to the mRNA-ribosome complex, which means that part of the ribosome is weakened for the conversion of protein synthesis.

Aims and Objectives

Hypotheses

Outline of dissertation / thesis structure

Introduction

Laser

Laser applications

When a beam is focused on the sample, the energy from the laser is absorbed by the atoms and they become excited as they gain enough energy to break free from the bonds on the sample surface, this produces a bright plasma as the particles expand [48] . Several types of lasers, such as argon, carbon dioxide, dye, erbium, excimer, Nd:YAG and others are used depending on the need for the current surgery or treatment.

Operating principles of a laser

Nd: YAG lasers

The UV-Vis absorption spectrum in Figure 4.9 (B) confirms the size defect of the silver nanoparticles. Sportelli et al., "The advantages and disadvantages of using laser ablation synthesis for the production of silver nano-antimicrobials," Antibiotics, vol. Zhigilei, “The effect of pulse duration on nanoparticle generation in pulsed laser ablation in liquids: Insights from large-scale atomistic simulations,” Phys.

Venugopal et al., "The impact of anticancer activity of Beta vulgaris extract-mediated biosynthesized silver nanoparticles (ag-NPs) against human breast (MCF-7), lung (A549), and pharyngeal (Hep-2) cancer cell lines," J.

Figure 2.9 Schematic diagram of a Nd:YAG laser [65].

Laser Ablation Synthesis in Solution

Spherical bubble dynamics

As shown in Figure 2.10, the radial position within the fluid is indicated by the distance, r, from the center of the bubble; the pressure, p(r, t), radial outward velocity, u(r, t), force, F, and temperature, T(r, t), in the fluid will be so denoted. The liquid cavitation parameters can be derived based on the Rayleigh-Plesset (RP) equation describing the evolution of the bubble and its physical properties [79]. Where, R, is the bubble radius, p, is the surrounding pressure, 𝜌𝐿, is the liquid density, 𝑣𝐿 is the viscosity of the liquid, and S, is the surface tension of the bubble-liquid interface.

Taking 𝑃∞(𝑡) as the external pressure surrounding the bubble and 𝑃𝐵(𝑡) is the pressure inside the bubble.

Figure 2.13 Schematic of a spherical bubble in an infinite liquid [79].

Bubble contents

The shapes of silver nanoparticles produced were generally spherical in all sample tests. This research was designed to synthesize pristine silver nanoparticles in water using pulsed laser ablation. Jayaraj, “Synthesis of Silver Nanoparticles by Liquid Phase Pulsed Laser Ablation for Antibacterial Applications,” vol.

Reich et al., "Pulsed laser ablation in liquids: impact of bubble dynamics on particle formation", J.

Ablation medium

Silver target ablation in water

Molecules such as hydroxyl groups can further attach to the nascent surface of silver nanoparticles, which can lead to highly charged surfaces that contribute to the electrostatic stabilization of the synthesized nanoparticles [89]. Ultrasonic and adiabatic propagation of the plasma cloud towards the liquid environment, cooling of the plasma and formation of cold clusters. By quenching the plasma, the clusters produced encounter solvent molecules and surfactants in the solution, causing some chemical reactions and confinement effects.

Thus, it would be difficult to achieve a large improvement of the nanomaterial productivity just by extending the laser irradiation times.

Doxycycline conjugated silver nanoparticles

Importance of the Research

Research Limitations

Introduction

Experimental layout

Ablation chamber

Identification of the elements within the solution was done using energy dispersive X-ray spectroscopy (EDS or EDX), and ultraviolet-visible spectroscopy (UV-VIS) was used to confirm the optical band gap of the silver nanoparticles. UV-VIS spectroscopy and Raman spectroscopy were used to confirm the synthesis of doxycycline silver nanoparticles in solution. The result of the research was the development of doxycycline silver nanoparticles and all the aforementioned procedural steps were followed critically.

Tajdidzadeh et al., "Synthesis of silver nanoparticles dispersed in various aqueous media using laser ablation," Sci. Muniz-Miranda, "Antibacterial activity of silver nanoparticles obtained by pulsed laser ablation in pure water and in chloride solution," Beilstein J. Liu et al., "Continuous biosynthesis of silver nanoparticles in a hydrodynamic cavitation device and modeling of the process by numerical simulation strategy,” J.

Figure 3.4 The diagram shows the image of the Hewlett Packard model 54502A oscilloscope used for the Nd:YAG pulse width measurement

Experimental arrangement for the synthesis of silver nanoparticles in solution using

Experimental procedure

Once the system was ready to begin ablating the target, the alignment of the laser entering the ablation chamber was double-checked by running the laser at reduced energy. The collected samples were characterized using a high-resolution transmission electron microscope (HR-TEM, model: Japanese electro-optical laboratory JEM-2100). After characterization was done, the results obtained were used to select the right wavelength and the ablation time that yielded high quality AgNPs.

Measurement of laser parameters

Laser Pulse duration measurement

The intensity of a laser irradiation

UV-Vis Spectroscopy

It typically uses the measurement of the electromagnetic radiation intensity as a function of the wavelength of the radiation [101]. When UV-visible light hits the substance, some of the light will be absorbed in the molecules of the compound, while the rest will be transmitted through it [100]. By analyzing the UV-VIS spectrograph, you can quickly determine the qualitative and quantitative properties of the nanoparticles.

The experimental parameters can be adjusted according to the shape and size of the nanoparticles required.

High Resolution Transmission Electron Microscopy

The lower magnifications are used to determine the size distribution of the nanoparticles and the higher resolutions are used to determine the morphology and internal structure of the nanoparticles. The most common mode of operation is when the electrons are forward scattered or transferred when they encounter the sample [105]. After ultra-sonicating the sample solution, further testing was performed on EDX to identify the elements present.

The data collected came in the form of numerical values ​​or graphs and the results were discussed in the following chapter.

Raman spectroscopy

A change in the molecular polarization potential or amount of distortion of the electron cloud with respect to the vibrational coordinate is necessary for a molecule to exhibit a Raman effect. The pattern of shifted frequencies is determined by the rotational and vibrational conditions of the sample [99].

Figure 3.10 Jablonkski energy diagram depicting electronic transitions of several processes in an excited atom resulting in the emission of photons of deferent energies [99]

Precautions

Cleaning and preparation

This research project was set up to study the synthesis and optimize the production of doxycycline silver nanoparticles using pulsed laser ablation synthesis in solution. The synthesized doxycycline silver nanoparticles can be used to test their effectiveness in inhibiting viral replication. Silver nanoparticles (AgNPs), developed by pulsed laser ablation in solution, allow the preparation of stable silver colloids in pure water without capping or stabilizing agents.

Kemp et al., "Gold and silver nanoparticles conjugated with heparin derivative possess anti-angiogenesis properties," Nanotechnology, vol. Silva et al., "On the synergy between silver nanoparticles and doxycycline against inhibition of: Staphylococcus aureus growth," RSC Adv., vol .Qayyum et al., “Laser synthesis of surfactant-free silver nanoparticles for toxic dye degradation and SERS applications,” Opt.

Figure 4.16 Shows the EDS/EDX spectrum of a silver nanoparticle sample

Introduction

Silver nanoparticles data analysis

UV-VIS absorption spectroscopic analysis of AgNPs

The Raman spectroscopy confirms that we had successfully produced pristine silver nanoparticles in water solution. This method was chosen due to its simplicity in tuning the properties of silver nanoparticles. To develop the required size and shape of pristine silver nanoparticles, a Nd:YAG, Q-switched combined 1064 nm and 532 nm wavelength pulsed laser was used.

Silva et al., “Doxycycline conjugated with polyvinylpyrrolidone-encapsulated silver nanoparticles: a polymer's malicious touch against Escherichia coli,” RSC Adv., vol.

High-resolution transmission electron microscopic analysis of AgNPs

Energy dispersive X-ray spectroscopic analysis of AgNPs

Doxycycline silver nanoparticle results

Raman spectroscopic analysis of doxycycline silver nanoparticles

However, these drugs can be developed and conjugated to silver nanoparticles using the same method. This research continues to combine pristine silver nanoparticles with doxycycline to enhance its antiviral activity. Malawong et al., “Silver nanoparticles enhance the antimicrobial efficacy of antibiotics and restore that efficacy against the melioidosis pathogen,” Antibiotics , vol.

Wei, “Hydrodynamic cavitation enhances silver nanoparticle biosynthesis at room temperature and its mechanism,” Mater.

Figure 4.18 the image for the Raman spectrum produced by doxycycline silver nanoparticles

UV-VIS absorption spectroscopic analysis of doxycycline-AgNPs

Conclusion

Doxycycline was used as an ionophore, as its complex formation with silver nanoparticles was reported to have the best antiviral inhibitory activities. To exploit the virus replication inhibitory properties of silver nanoparticles, which derive mainly from its physical and surface chemical properties, promotes the use of combined 1064 nm and 532 nm pulsed laser ablation in water as the preferred approach. This research helped shed light on a topic like water cavitation that is still not very well understood.

Many other drug compounds could have been chosen to be used as the ionophore conjugated to AgNPs, such as hydroxychloroquine, quercetin or ivermectin.

Revisiting the aims and objectives

Challenges

Future possibilities

Summary conclusions

UV-visible absorption spectrum was used to rapidly test the properties of the newly synthesized silver nanoparticles and the results were used to rapidly optimize the production process. The HRTEM images were analyzed and from the data obtained, frequency histogram was plotted to clearly display the distribution of sizes and surface area of ​​the formed nanoparticles. The identification of the elements in the nano material composition was done using an Energy dispersive X-ray spectroscopy (EDS or EDX), and the (UV-VIS) was used to confirm the absorption band gap of AgNPs.

All the results obtained and recorded were consistent with the results reported in the literature review.

Chemometric procedure

Ahmad et al., "Recent advances in combinatorial cancer therapy via multifunctionalized gold nanoparticles," Nanomedicine, vol. De Giacomo et al., "Cavitation dynamics of laser ablation of bulk and filamentary metals in water during nanoparticle production," Phys. Dell'Aglio et al., "Silver and Gold Nanoparticles Prepared by Pulsed Laser Ablation in Liquid to Probe Their Interaction with Ubiquitin," Appl.

Mohammadkarimi et al., "Synthesis of Silver-Doxycycline Complex Nanoparticles and Their Biological Evaluation on MCF-7 Cell Line of the Breast Cancer", J.