روایتی بینکاری نظام کے ارتقائی مراحل کا تحقیقی جائزہ

The concept of keeping wealth in a safe place dates to centuries. Ancient civilizations had diverse means of storing wealth in the form of crops, cattle, precious metals etc. The evolution of modern banking practice began with the introduction of receipts which were exchanged against precious metals and coins deposited to goldsmiths for safe keeping. Whenever the need for payments and transactions arose the holder of the receipts used to utilize the receipts as guarantee. The society used to honor these receipts as they carried the same weight as other precious metals. Receipts were swapped in place of precious metals and thus for all practical purposes paper was introduced as currency in the society. With the advent of currency notes the system of traditional banking came into being. Since then the banking system has gone through continuous change. The present banking system is geared up to meet the present and the future requirements of modern age. In the contemporary world money is now being steadily replaced by banknotes, cheques, pay orders, bank draft, ATM cards, debit cards, credit cards, e-banking.

Evaluation of Biosensing and Antimicrobial Applications of Gold and Silver Nanoparticles

Understanding is on the rise concerning the use of nanomaterials environmental/health management solutions. In the current study, silver and gold nanoparticles (AgNPs and AuNPs respectively) were prepared for this purpose and characterized with UV–visible, transmission electron microscopy (TEM), dynamic light scattering and zeta potential. First, spherical and prism colloidal AgNPs were capped with poly-L-arginine and tested for their biological activity. Prism shaped AgNPs exhibited stronger growth inhibitory effects against E.coli, P. aeruginosa and S. enterica, where MBC was 0.65 μg/mL), whereas it was 2.7 μg/mL for spherical ones. Maximum mortality percentage of HeLa cell line was 80% for AgNP-prism nanocomposite, capped with poly L arginine and polyvinyl pyrollidone (PLA-PVP) at 11 mg/mL concentration. It was also found that PVP capped AgNP nanoprisms were able to detect mercury (Hg2+) by colorimetric estimation (blue to yellow color); TEM and spectrophotometry revealed the change in morphology of the prismatic to spherical shaped AgNPs; energy dispersive x-ray spectroscopy (EDX) also confirmed the formation of nano-alloy with Hg2+. Linear relationship was found between surface plasmon resonance (SPR) for the position shift of the AgNP nanoprisms and Hg2+ (Conc. 0-5 μmol/L conc.; detection limit, 0.5 μmol/L; pH, 7 – 9). Additionally, AuNP nanoshell conjugates were using for their biosensing capacity for bacteria, such as E. coli, P. aeruginosa, S. enterica and S. aureus. by colorimetric method (color change, yellow to red); bacterial concentrations upto 10 CFU/mL could be detected easily. AuNP-conjugates comprised of cetyl trimethyl ammonium bromide (CTAB) capped AuNP nanoshells , conjugated with the enzyme, β-galactosidase. The bacterial surfaces (bearing electronegative surface functional groups) could electrostatically attract CTAB capped AuNP nanoshells, whereas the enzyme, β-galactosidase was freed meanwhile. Here, chlorophenol-red-β-D-galactopyranoside (CPRG), which is yellow in color, was used as substrate to attract β-galactosidase (freed from the AuNP nanoshell complex), resulting in red chromophore chlorophenol red. With the increased concentration of bacterial cell, more absorption was seen by spectrophotometer, which clearly proved our hypothesis. Hence our studies suggest the possible antibacterial, biosensing, and anticancer applications of AgNPs and AuNPs.