Department of Biotechnology

About: Department of Biotechnology is a government organization based out in New Delhi, India. It is known for research contribution in the topics: Population & Silver nanoparticle. The organization has 4800 authors who have published 5033 publications receiving 82022 citations.

Surface Engineered Dendrimers in siRNA Delivery and Gene Silencing

Abstract: Background Therapeutic efficacy of dreadful diseases like cancer, HIV (Human Immunodeficiency Virus) can be enhanced by delivering molecules which regulate function at gene level rather than at receptor level. Silencing RNA is one such approach recently used to silence target gene expressed diseases; and thereby reduce target protein levels. Many of the non-viral vectors are proved to act as carriers for silencing RNA. Dendrimers being one of them have less size, low poly dispersibility index, water solubility, multivalence, and easy surface modification. Many such surface modifications have been carried out to improve the delivery potential of small interfering RNA (siRNA) modified dendrimers compared to simple plain dendrimers. Methods Dendrimer was taken as a core whose surface was modified with fluorine, amino acids, phosphate, lipids, folate, specific antibody or RGD (Arg-Gly-Asp). The purpose of these modifications was to increase the therapeutic siRNA efficiency, lower the toxicity and improve the targeting potential of dendrimers. Results Fluorinated dendrimers have highest electronegativity and highest siRNA loading capacity. Amino acid functionalized dendrimers are made up of endogenous amino acids which improve biocompatibility of dendrimer and endosomal escape. Carbosilane dendrimers increase the gene transfection ability of tissues to be treated. Phosphate dendrimers having hydrophobic backbone and hydrophilic surface increase the permeability towards targeted tissue. Lipid based dendrimer causes endosomal escape and improves the permeability of dendrimers. Targeting of specific tissues is achieved by coupling dendrimer with folate, RGD and specific antibody, thereby reducing off target effect. Conclusion Thus, surface modified dendrimers render a complete pack which offers increased siRNA loading, increased transfection and permeability, efficient targeting, endosomal escape and protecting siRNA from degradation by RNase and other such enzymes. The objective of this manuscript is to provide different approaches currently available for surface modifications of dendrimers and their overall effect on transfection ability of siRNA to target tissues.

Nanostructured microspheres of silver @ zinc oxide: an excellent impeder of bacterial growth and biofilm

Abstract: Nanostructured (metal/semiconductor) Ag@ZnO a photoactive material is synthesized by facile hydrothermal method. The FESEM analysis of as synthesized Ag@ZnO nanostructures showed formation of submicron-sized microspheres, composed of small nanoparticles of size in the range of 10–20 nm. The as synthesized Ag@ZnO nanostructures possess wurtzite hexagonal structure of ZnO with band edge transition to visible region due to surface plasmon effect of silver which ultimately is responsible for the improved photocatalytic performance. The photocatalytic action of Ag@ZnO nanostructures impede the growth of model organisms Bacillus subtilis NCIM 2063 and Escherichia coli NCIM 2931, and biofilm in Pseudomonas aeruginosa O1. The present study is important as it introduces an excellent functionality of Ag@ZnO, an agent for impeding the biofilm and bacterial communities inside the biofilm.

Influence of altitudinal variation on the antioxidant potential of tartar buckwheat of Western Himalaya

Abstract: In the present work, the effect of altitudinal variations on the total phenol, flavonoid, and antioxidant potential of seeds and hull of Tartar buckwheat collected from 15 different locations of Western Himalaya has been investigated. Methanolic and acetonic extracts of seed and hull powder showed significantly increasing amounts of total polyphenol content, and antioxidant potential with rising altitude. Methanolic extract of seed and hull powder were found to have significantly greater polyphenol, and antioxidant potential as compared to acetonic extract. The methanolic seed extract of Inderdhara (3,133 m) showed the maximum total phenolic content 1,651 μg gallic acid equivalent/50 mg of dry weight. The methanolic seed extract of Inderdhara showed the maximum antioxidant activity (77.29±1.2%) and antiradical activity (55.5±0.5%) also. The results of this study exhibited good correlation with total polyphenol and antioxidant potential in all the samples followed by the increasing tendency towards rising altitude.

Wound healing and protease inhibition activity of Bacoside-A, isolated from Bacopa monnieri wettest

Abstract: Bacopa monnieri (L.) Wettest. (Scrophulariaceae) is a well-known medicinal herb. In the Indian system of medicine it is known as Brahmi (Sanskrit) and Indian water hyssop. Methanolic extract of Bacopa monnieri and its isolated constituent Bacoside-A were screened for wound healing activity. Bacoside-A was screened for wound healing activity by excision, incision and dead space wound on Swiss albino rats. Significant wound healing activity was observed in both extract and the Bacoside-A treated groups. The SDS-PAGE caseinolytic zymogram analysis of inhibition of matrix metalloproteases (MMPs) enzyme from the excision wound by Bacoside-A, an isolated constituent, was done with the concentrations 100 and 200 micromg/ml. In Bacoside-A treated groups, epithelialization of the excision wound was faster with a high rate (18.30 +/- 0.01 days) of wound contraction. The tensile strength of the incision wound was increased (538.47 +/- 0.14 g) in the Bacoside-A treated group. In the dead space wound model, the weight of the granuloma was also increased (89.15 +/- 0.08 g). The histological examination of the granuloma tissue of the Bacoside-A treated group showed increased cross-linking of collagen fibers and absence of monocytes. The wound healing activity of Bacoside-A was more effective in various wound models compared to the standard skin ointment Nitrofurazone.