Title
Selective and sensitive determination of antidote of heparin using Ag-GQDs by optical methods
Author
Sinduja Bharathi, N.S.K Gowthaman, S Abraham John
Year
2018
Journal
Analytical Methods
Abstract
Determination of polyanionic drug, heparin has been reported in the literature by various spectral techniques at the expense of polycationic drug, protamine. But, determination of protamine in the presence of heparin by optical methods has not been reported so far. Since administration of protamine is associated with different side effects its accurate determination is essential in the presence of heparin. The present study reports the sensitive and selective determination of protamine in the presence of heparin by colorimetric, spectrophotometric and spectrofluorimetric methods using GQDs capped silver nanoparticles (Ag-GQDs) for the first time. The yellow colour of the Ag-GQDs containing heparin immediately turns to red while adding 100 ng/mL protamine. The obtained color change is due to increase in the Ag-GQDs size from 9 to 15 nm which was confirmed by HR-TEM studies. On the other hand, the surface plasmon resonance (SPR) band of Ag-GQDs at 411 nm was decreased and a new peak was appeared at 520 nm after the addition of protamine. While adding each 10 ng/mL protamine to Ag-GQDs, the emission intensity at 451 nm increases linearly with a correlation coefficient of 0.991 and the limit of detection was found to be 0.05 ×10-9 g/mL (S/N =3). Further, the selective determination of protamine was achieved in the presence of heparin and other common interference using Ag-GQDs. The practical application of the present sensor was displayed by determining protamine in blood serum.
Instrument
FP-8500
Keywords
Fluorescence, Nanostructures, Chemical stability, Materials, Sensors