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Calculation:
1. Concentrations of CNPs:
The molarity of pure phase cerium oxide (CeO 2
; molecular weight 172.11 g/mol) in 1 g/L was calculated as,
รท 172. 11
= 5. 8 ร 10
โ 3
From this concentration, dilutions were made for larval and adult experiments.
Larval experiment:
0.01 mM CNPs was used in larval experiments; the volume of stock CNP solution required to produce 40 mL
(experimental volume):
( 0. 01 ๐๐ ร 40 ๐๐ฟ) รท 5. 8 ๐๐ = 0. 069 ๐๐ฟ
Adult experiment:
1 mM, 0.5 mM and 0.1 mM CNPs was used for adult experiments. Dilutions from stock concentration for these
experiments were prepared as such:
a. 1mM CNPs
( 1 ๐๐ ร 1 ๐๐ฟ) รท 5. 8 ๐๐ = 0. 172 ๐๐ฟ
Thus 0.172 mL of 5.8 mM CNPs was added to 0.828 mL water to make 1 mM solution
b. 0.5 mM CNPs
( 0. 5 ๐๐ ร 1 ๐๐ฟ) รท 5. 8 ๐๐ = 0. 086 ๐๐ฟ
Thus 0.086 mL of 5.8 mM CNPs was added to 0.914 mL water to make 0.5 mM solution
c. 0.1 mM CNPs
( 0. 1 ๐๐ ร 1 ๐๐ฟ) รท 5. 8 ๐๐ = 0. 0172 ๐๐ฟ
Thus 0.0172 mL of 5.8 mM CNPs was added to 0.9828 mL water to make 0.1 mM solution
2. Concentrations of AgNO 3 :
Larval experiment:
Firstly, a stock solution of 1 mM AgNO 3
was produced as:
ร 0. 001
ร 1 ๐๐ฟ = 0. 170 ๐
3
0.025 mM AgNO 3
was used in larval experiments and produced by dilution from stock:
( 0. 025 ๐๐ ร 40 ๐๐ฟ) รท 1 ๐๐ = 1 ๐๐ฟ
1 mL of 1 mM AgNO 3
was added to 39 mL water to make 0.025 mM AgNO 3
Calculating mg/L (ppm) of silver in 0.025 mM AgNO 3
Molecular weight of AgNO 3
is 169.87 g/mol; so 1 mM AgNO 3
has 169.87 ฮผg/mL of AgNO 3
0. 025 ร 10
โ 3
3
ร
3
ร 169. 87
The atomic weight of Ag is 107.87 g/mol; so 1 mM has 107.87 ฮผg/mL
0. 025 ร 10
โ 3
3
ร
3
ร 107. 87
Adult experiment:
a. 0.025 mM AgNO 3
( 0. 025 ๐๐ ร 1 ๐๐ฟ) รท 1 ๐๐ = 0. 025 ๐๐ฟ
0.025 mL of 1 mM AgNO 3
was added to 0.975 mL blood or sugar solution to make 0.025 mM AgNO 3
Per the above calculation, 0.025 mM equates to 4.24 ppm of AgNO 3
or 2.697 ppm Ag
b. 0.050 mM AgNO 3
( 0. 050 ๐๐ ร 1 ๐๐ฟ) รท 1 ๐๐ = 0. 050 ๐๐ฟ
0.050 mL of 1 mM AgNO 3
was added to 0.950 mL blood or sugar solution to make 0.050 mM AgNO 3
Calculating mg/L (ppm) of silver in 0.050 mM AgNO 3
leads to twice the concentration calculated for 0.025 mM
(8.48 ppm AgNO 3
or 5.394 ppm Ag).
3. Calculation of amount of Ag in doped nanoparticles:
XPS showed that 0.72 atomic percent (at%) of Ag is incorporated in AgCNPs (per Avantage software). The ratio of
Ce
3+
to Ce
4+
redox states in each formulation was determined analytically. First, a baseline correction was fit to the
data using a smart baseline function (Avantage). Next, peaks were fit using curves constrained by state-specific
properties (e.g. separation between multiplet spin states, relative peak heights for associated peaks split due to spin-
orbit coupling). Fitting was optimized by least squares regression (Avantage) and the peaks associated with Ce
3+
and
Ce
4+
were integrated numerically. Sum peak contributions for each state were then normalized as,
[
3 +
]
3 +
3 +
4 +
0
โฒ
0
โฒ
โ[(๐ฃ
0
โฒ
0
โฒ
โฒโฒ
โฒโฒโฒ
โฒโฒ
โฒโฒโฒ
)]
Where โvโ peaks are related to emissions from the Ce3d5/2 and โuโ peaks to Ce3d3/2 multiplets respectively, per
literature convention, along with associated satellite peaks (arising from complex, final state emissions). The average
Ce
3+
/Ce
4+
ratio for the silver-modified ceria formulation was determined as 37.4%. Atomic percent silver (produced
using Avantage analysis software, with respect to spectral contributions from O, Ag, and Ce) and relative Ce
3+
content
were subsequently used in describing the silver content per mass of nanomaterial.
We consider cerium and oxygen percentages as arising from proportions of the oxide in each redox state in fixed molar
ratios, weighted by the fraction of each cerium redox state. Mass percents of silver were thereby calculated from the
molarities of total atom proportions:
