5. The use of silver as an antimicrobial agent has increased of late, particularly
in wound dressings, topical agents, and medical devices
Colloidal silver is widely purchased by people who ingest the metal in
expectation of health benefits
Chronic exposure to silver and silver compounds leads to argyria and
argyrosis, and to other symptoms such as headaches, stomach distress,
fatigue, skin irritation, or more serious neurological, renal, or hepatic
complications
U.S. Environmental Protection Agency (EPA) has set a maximum contaminant
level (SMCL) for silver at 0.1 mg/L 4
6. Thiamine, also well-known as thiamin or vitamin B1
(Colorless-organosulfur)
Vitamin B1 is an important component of balanced
healthy diets
Thiamine deficiency has been linked to the
development of a number of diseases, including the development of autism,
Alzheimer’s disease and cancer.
Naturally, thiamine is present in oats, rice, potatoes, eggs and grains.
WHO recommended normal blood level amounts to above 10 Fg/100ml as
thiamine 5
10. (a) UV-vis spectrum of
D-Mannitol-CDs,
(b) Emission spectrum
D-Mannitol-CDs,
Inset: Photographs of
MCDs (i) Day light and
(ii) UV light
9
11. 3D plot of the emission
spectra of MCDs
obtained with different
excitation wavelengths
ranging from 300 to 400
nm.
10
Emission spectra of MCDs with different excitation
16. UV-vis spectra of MCDs in the presence of different concentration Ag+ ions. Linear range: 0.163 to 1.77 µM Inset:
Photographs (i) before and (ii) after the addition 1.77 µM Ag+ ion (iii) Correlation diagram.
115
LOD = 1.3 nM
UV-vis
17. 116
Emission spectra of MCDs in the presence of different concentration Ag+ ions. Linear range: 0.0817 to 0.963 µM .
Inset: UV light Photographs (i) before and (ii) after the addition 0.963 µM (iii) Correlation diagram.
LOD = 0.5 nM
PL
18. UV-vis spectra of MCDs-AgNPs in the presence of different concentration Thiamine. Linear range: 0.163 to1.77
µM. Inset: Photographs (i) before and (ii) after the addition 1.77 µM of Thiamine (iii) Correlation diagram.
117
LOD = 2.58 nM
UV-vis
19. 118
Emission spectra of MCDs-AgNPs in the presence of different concentration Thiamine. Linear range: Linear range:
0.0817 to 0.963 µM. Inset: UV light Photographs (i) before and (ii) after the addition 0.963 µM of Thiamine (iii)
Correlation diagram.
LOD = 0.577 nM
PL
20. 119
Emission spectra of
only MCDs in the
presence of different
concentration
Thiamine(a) 0, (b)
2.44, (c) 4.86, (d) 7.26,
(e) 9.63 and (f)
12.0×10-7 M. Inset:
large scle
25. 24
We have successfully synthesized M-CDs at Hydrothermal
method
The synthesized MCDs was well characterized by several
techniques
Then, MCDs-AgNPs was used as probe for the detection of
Ag+ ions and Thiamine and LOD was found to be 0.5 and
0.577 nM by spectrofluorimetry and carried out selectivity
Finally we have discuss possible mechanism of detection
Ag+ ions and Thiamine using MCDs
26. 25
Future characterization HR-TEM, FT-IR, Mass, XRD and
DLS spectroscopy
Then, Sensor system applying real sample analysis
Preparation of portable kit
Validation method