Browsing by Author "Hassan, Syeda Sara"

Now showing 1 - 2 of 2

Synthesis of L-Cysteine Capped Silver Nanoparticles in Acidic Media at Room Temperature and Detailed Characterization
(SPRINGER, VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS, 2018) Panhwar, Sallahuddin; Hassan, Syeda Sara; Mahar, Rasool Bux; Canlier, Ali; Sirajuddin; Arain, Munazza; 0000-0002-1966-0397; AGÜ, Mühendislik Fakültesi, Malzeme Bilimi ve Nanoteknoloji Mühendisliği Bölümü
This work reports a simple and one pot synthesis of water dispersible l-cysteine stabilized silver nanoparticles (l-CYS-AgNPs) in an acidic media. Silver nanoparticles were synthesized within few minutes of reaction time (< 5 min) at room temperature without needing to heat and use of any hazardous organic solvents. Prepared nanoparticles were characterized by UV-Visible spectroscopy, Fourier transform infrared spectroscopy, transmission electron microscopy, atomic force microscopy, X-ray diffraction and zeta potential analysis, respectively. Surface plasmon resonance band of AgNPs which was observed at 392 nm by UV-Visible spectroscopy indicated successful formation of l-CYS-AgNPs in acidic media. Imaging techniques showed that AgNPs possess spherical morphology and average size of 25 nm. Nanoparticles were stable for more than 2 months when stored at ambient temperature. This approach is a facile and rapid one pot synthesis which can be stored as a homogenous aqueous dispersion for more than 2 months. Being stabilized by a sulfur-containing amino acid (l-cysteine) and the synthesis carried out in a moderately acidic media (pH 5.3) are distinctive aspect of this work. These stable l-CYS-AgNPs could be used as a catalyst and sensor applications for advanced perspective against water pollution and industrial effluents.
Ultra-rapid catalytic degradation of 4-nitrophenol with ionic liquid recoverable and reusable ibuprofen derived silver nanoparticles
(ELSEVIER SCI LTD, THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND, 2018) Hassan, Syeda Sara; Carlson, Krista; Mohanty, Swomitra Kumar; Sirajuddin; Canlier, Ali; 0000-0002-4288-2641; AGÜ, Mühendislik Fakültesi, Malzeme Bilimi ve Nanoteknoloji Mühendisliği Bölümü
This study reports a one-pot and eco-friendly method for the synthesis of spherical ibuprofen derived silver nanoparticles (IBU-AgNPs) in aqueous media using ibuprofen analgesics drug as capping as well as reducing agent. Formation of AgNPs occurred within a few min (less than 5 min) at room temperature without resorting to any harsh conditions and hazardous organic solvents. Synthesized AgNPs were characterized with common analytical techniques. Transmission electron microscope (TEM) images confirmed the formation of spherical particles having a size distribution in the range of 12.5 +/- 1.5 nm. Employment of IBU analgesic aided the control of better size distribution and prevented agglomeration of particles. Such AgNPs solution was highly stable for more than two months when stored at ambient temperature. The IBU-AgNPs solution showed excellent ultra-rapid catalytic activity for the complete degradation of toxic 4-nitrophenol (4-NPh) into non-toxic 4-aminophenol (4-APh) within 40 s. AgNPs were recovered with the help of water insoluble-room temperature ionic liquid and reused with enhanced catalytic potential. This method provides a novel, rapid and economical alternative for the treatment of toxic organic pollutants to maintain water quality and environmental safety against water pollution. It is extendable for the control of other reducible contaminants in water as well. Furthermore, this catalytic activity for an effective degradation of organic toxins is expected to play a crucial role for achieving the Sustainable Development Goal 6 set by United Nations. (C) 2017 Elsevier Ltd. All rights reserved.