Figure S1: Comparison of DLLME in three different conditions

Figure S2: Optimization of type of disperser solvent

Figure S3: Optimization of amount of disperser solvent

Figure S4: Chromatogram of blank sample in (A) positive ion and (B) negative ion mode

FactorANOVA; Var.:AREA; R-sqr= 0.9734; Adj: 0.9526 (2**(3) central composite, nc=8 ns=6

nc0=1 ns0=1 Runs=16 (2**(3) central composite, nc=8 ns=6 nc0=1 ns0=1 Runs=16 (2**(3) central composite, nc=8 ns=6 nc0=1 ns0=1 Runs=16 (Design: 2**(7-4) design 3 factors, 1

Blocks, 18 Runs; MS Residual=289878E6DV: AREA

SS df MS F p(1)AS (L) 8.291360E+11 1 8.291360E+11 2.860296 0.129254

AS (Q) 2.049747E+12 1 2.049747E+12 7.071075 0.028844(2)AT(L) 1.051118E+12 1 1.051118E+12 3.626073 0.093358

AT(Q) 1.088858E+11 1 1.088858E+11 0.375627 0.556970(3)ST (L) 7.725264E+11 1 7.725264E+11 2.665008 0.141221

ST (Q) 6.957894E+10 1 6.957894E+10 0.240029 0.6373381L by 2L 1.267718E+10 1 1.267718E+10 0.043733 0.8395781L by 3L 5.190529E+10 1 5.190529E+10 0.179059 0.6833292L by 3L 1.395372E+09 1 1.395372E+09 0.004814 0.946390

Error 2.319022E+12 8 2.898777E+11Total SS 7.893145E+12 17

Table S1: ANOVA table obtained for CCD

Extraction methods Instrumentation Number of

NTsSample matrix LOD Ref.

MISPE FASI/CE-UV 4 Human urine 0.34-0.5 µg L -1 [46]

SPME GC-MS/MS 3 Human urine 0.3-1.23 µg L-1 [47]

SPME LC-MS/MS 4 Rat brain 0.006-0.01 µg L -1 [48]

In situ DUDLLME LC-MS/MS 6 Rat brain 0.003-0.006 µg

L -1 [49]

CM-LPME-SSP HPLC-ECD 4 Human

urine 5.5-10.8 µg L -1 [50]

MEPS HPLC-ED 3 Human urine 2-20 µg L -1 [51]

SPE LC-MS/MS 4 Human urine 0.25-2 µg L -1 [52]

IL-UA-DLLME LC-MS/MS 15

Rat brain, blood and

cell samples

0.021-0.912 µg L-1

This wor

k

Table S2: Comparison of proposed method with most of the recent technique used for analysis of NTs

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