1. Introduction
In recent times, nanotechnology is an extremely emerging and developing field having tremendous implications both in academia and industry. A number of physical, chemical and biological methods have been adopted to formulate different kind of nanoparticles. The physical methods of preparation involve high pressure and temperature. The techniques are also quite expensive [1-4]. Also, in many chemical pathways, the chemicals used are very harmful and toxic to the environment as well as for biological systems. The by-products derived from the chemical methods are also very toxic. So, the need for a suitable cost-effective and efficient pathway that does not produce toxic substances, without affecting the environment is highly demanding [5,6]. Adoption of biological procedure is one of the best ways to solve the above discrepancies to the synthesis of nanoparticles. The mother nature has provided a great resource in this regard. Different microorganisms like bacteria, actinomycetes, fungi and algae as well as plants and plant extracts are employed as the biological template in the synthesis of nanoparticles [7-9]. Recently, plant extracts have been widely used in the synthesis of functionalized nanoparticles. The typical advantage in the phytosynthesis of nanoparticle using plant extracts are the use of water as only solvent, being essentially abundant, green and safe solvent. The nanoparticle biosynthesis using biological materials is also very simple and does not need special conditions that are required in chemical and physical ways [10-12]. The reduction potential of biological materials is higher than that of microbial culture media, and as a result, the time required for the nanoparticle formation is comparatively less. The pollution created during the nanoparticle biosynthesis using biological materials is almost zero. As a result, the nanoparticle biosynthesis using biological materials has very low environmental impact, highly compatible with the environment [9-11]. However, the speed of production, quality and other properties of nanoparticles depend on many factors such as the nature of biological materials, reaction time, temperature, pH, metal salt concentration, and extract concentration. The use of biological materials due to their environmental compatibility with the abundance are usually prioritized. Also, due to their lack of need for special nutrients and conditions for growth, biological materials are considered the best option for the nanoparticle production [7-10].
Nanoparticles are designed in such a way that they can carry a higher dose of medicine with them and deliver it to the target area that is affected by cancer. In fact, these particles are not a threat to healthy body cells and only affect cancer cells and destroy them [11-13]. This method is considered a targeted treatment that attacks only the target cells and acts selectively. By this method on several patients, positive and satisfactory results have been obtained, which can be considered as part of the great developments of medical science in the field of cancer treatment [10-14].
With these inputs, we wish to report herein a competent biogenic synthesis of bio-functionalized tiny Ag NPs templated over the chitosan-starch mixed polymeric hydrogel. The biopolymers facilitate the binding of incoming Ag ions followed by green reduction to the corresponding NPs. The polar electron rich organo functions (OH, CH2OH, NH2) prevailed over the conjugate biopolymers also helps in the stabilization of the as-synthesized NPs by encapsulation or capping and preventing them from self-agglomerations. Based on the structure oriented anti-cancer activities of different bio-functionalized nanoparticles, the Ag NPs/CS-Starch bio-composite nanomaterial was employed in the determination of cytotoxicity and anti-leukemina activities against a number of corresponding cell lines like acute myeloid leukemia (32D-FLT3-ITD and Human HL-60/vcr), acute lymphoblastic leukemia (MOLT-3 and TALL-104), and acute T cell leukemia (Jurkat, Clone E6-1 and J.RT3-T3.5). In all of them the % cell viability decreases dose-dependently. In addition, the material was studied in the determination of antioxidant properties through the well known DPPH radical scavenging analysis, which in turn showed outstanding activity, being referenced to BHT molecule.