A review on preparation methods of SNPs and their biomedical applications

Abstract

Researchers have identified Silver Nano Particles (SNPs) as a key area of interest because of their unique shape and size dependent biomedical properties. They have discovered and invented a variety of methods for the synthesis of SNPs such as microwave irradiation techniques, laser ablation synthesis, biological synthesis, photochemical synthesis and chemical synthesis etc. In this review paper we overview the preparation of SNPs through various synthesis methods and also their applications in the bio-medical field. The main aim of this paper is to keep up to date with the myriad ongoing synthesis methods of synthesis of NPs and also examine their applications especially in the field of medicine. Silver Nano Particles (SNPs)Silver (Ag) is a white colored, lustrous looking, physically soft, transition element metal having high thermal and electrical conductivity. It has been used by humans earlier than the recorded history due to its ornamental, medical and therapeutic benefits even before realizing that microbes are the causative agents of infections. It is used by people in many forms such as solutions, foils, coins, vessels, sutures, and in colloids such as lotions, ointments etc. It is one of the most prominent therapeutic elemental agent in medicine for surgical infections and infectious diseases. The tangible advantages of silver have a bigger weightage than the intangible risk factors [1].Nanoscience is a novel multidisciplinary subject that depends on the basic physical and chemical properties displayed by nano level objects [2,3]. Nanoparticles have been shown to display amazing electromagnetic, surface optical and chemically catalytic characteristics than the macro bulk material owing to their extremely low volume to surface area ratio [4,5]. Metal nanoparticles such as silver show different colors due to their Surface Plasmon Resonance (SPR) phenomenon. It is a group oscillatory behavior of the free electrons of the metal nanoparticles having the same frequency of the light wave interactions, resulting in resonance, causing the SPR band to form in the infrared and visible region [6]. Nanoparticles, especially the metallic ones, whose production can be done through various methods, the usual ones being physical and chemical methods. The above-mentioned methods produce high purity, well-defined nanoparticles, but the reagents used in the synthesis are hazardous, energy consuming, expensive, toxic and not suitable for physiological or ecological applications. Research regarding the synthesis of metal nanoparticles was extensively covered in the past three decades, but research of nanosynthesis , based on plant extracts, bloomed only in the last ten years [7][8][9][10][11][12][13].Silver nanoparticles are finding themselves in the limelight due to their biological, chemical and physical properties that contributes to the bactericidal and fungicidal effects, catalytic activity and finds applications in nanobiotechnological research [14,15]. Doctors are beginning to use them in wound dressings as an...