Development of a supramolecular solvent–based extraction method for application to quantitative analyses of a wide range of organic contaminants in indoor dust

This study investigates the efficacy of supramolecular solvent (SUPRAS) in extracting a diverse spectrum of organic contaminants from indoor dust. Initially, seven distinct SUPRAS were assessed across nine categories of contaminants to identify the most effective one. A SUPRAS comprising Milli-Q water, tetrahydrofuran, and hexanol in a 70:20:10 ratio, respectively, demonstrated the best extraction performance and was employed for testing a wider array of organic contaminants. Furthermore, we applied the selected SUPRAS for the extraction of organic compounds from the NIST Standard Reference Material (SRM) 2585. In parallel, we performed the extraction of NIST SRM 2585 with conventional extraction methods using hexane:acetone (1:1) for non-polar contaminants and methanol (100%) extraction for polar contaminants. Analysis from two independent laboratories (in Norway and the Czech Republic) demonstrated the viability of SUPRAS for the simultaneous extraction of twelve groups of organic contaminants with a broad range of physico-chemical properties including plastic additives, pesticides, and combustion by-products. However, caution is advised when employing SUPRAS for highly polar contaminants like current-use pesticides or volatile substances like naphthalene. Supplementary Information The online version contains supplementary material available at 10.1007/s00216-024-05433-3.


Contents
Text S1 Instrumental analysis at RECETOX laboratories PAHs + Musks p-terphenyl was used as the internal standard and added after the final volume reduction.PAHs and musks were analyzed using an Agilent 8890A GC (Agilent Technologies, Inc., Santa Clara, CA, USA) equipped with a 60 m × 0.25 mm × 0.25 µm Rxi-5Sil-MS capillary column (Restek, Inc., France), coupled to a triple quadrupole Agilent 7000D MS (Agilent Technologies, Inc., Santa Clara, CA, USA).The temperature program for the GC oven started at 80 °C (2 min hold), then continued with 15 °C/min to 180 °C (no hold) and lastly 5 °C/min to 310 °C (20 min hold).The inlet temperature was 280 °C.The injection volume was 1 µl in pulsed-splitless mode.The carrier gas was helium with a 1.5 mL/min flow rate.The temperature of the GC-MS transfer line was 310 °C.The ion source was heated to 320 °C.The mass spectrometer was operating in selected ion monitoring (SIM) mode.Compound quantification was done using MassHunter Workstation 10.1 software (Agilent Technologies, Inc., Santa Clara, CA, USA) with an external calibration curve, with a linear range of 1 ng/ml to 1 µg/ml.Substituted PAHs PCB 95 was used as the internal standard and added after the final volume reduction.Nitroand oxy-PAHs were analyzed using an Agilent 7890 GC (Agilent Technologies, Inc., Santa Clara, CA, USA) equipped with a 30m × 0.25mm × 0.25 µm Rxi-5Sil capillary column (Restek, Inc., France), coupled to a Waters Xevo TQ-S MS (Waters Corporation, Milford, MA, USA).
The temperature program for the GC oven at 90°C (1 min hold), then increased at a rate of 40 °C/min to 180°C (0 min hold), followed by an increase of 5 °C/min to 320°C (6 min hold).The inlet temperature was set at 270 °C.The injection volume was 1 µl in splitless mode.The MS was operated under dry source conditions in multiple reactions monitoring (MRM) mode.The carrier gas used was helium with a 1.5 mL/min flow rate.NFRs PBDE 77 was used as the internal standard and added after the final volume reduction.NFRs were analyzed using Agilent 7890A GC (Agilent Technologies, Inc., Santa Clara, CA, USA) equipped with RTX-1614 size 15 m × 0.25 mm × 0.10 μm column (Restek, Inc., France), coupled to Waters AutoSpec Premier MS (Waters Corporation, Milford, MA, USA).The GC temperature program started at 80 °C (1 min hold), increased at a rate of 30 °C/min to 140 °C (0 min hold), followed by an increase of 4 °C/min to 175 °C (0 min hold), then increase at a rate of 8 °C/min to 270 °C (0 min hold) and finally at 15 °C/min to 325 °C (5 min hold).The injected sample volume was 2 µl at 250 °C in pulsed splitless mode.Helium was used as a carrier gas at 1 mL/min and 1.4 mL/min after 15 min.The MS was operated in EI+ and SIM mode at the resolution of >10000.PBDEs PBDE 77 was used as the internal standard and added after the final volume reduction.PBDEs were analyzed using Agilent 7890A GC (Agilent Technologies, Inc., Santa Clara, CA, USA) equipped with RTX-1614 size 15 m × 0.25 mm × 0.10 μm column (Restek, Inc., France), coupled to Waters AutoSpec Premier MS (Waters Corporation, Milford, MA, USA).The GC temperature program started at 80 °C (1 min hold), increased at a rate of 20 °C/min to 250 °C (0 min hold), followed by an increase of 1.5 °C/min to 260 °C (2 min hold) and finally by 25 °C/min to 320 °C (4.5 min hold).The GC/MS interface and ion source temperatures were 280 and 250 °C, respectively.The injected sample volume was 2 µl at 280 °C in pulsed splitless mode.Helium was used as a carrier gas at 1 mL/min and 1.4 mL/min after 15 min.The MS was operated in EI+ and SIM mode at the resolution of >10000.For BDE-209, the resolution was set to >5,000.PCBs + OCPs PCB 95 was used as the internal standard and added after final volume reduction.PCBs and OCPs were analyzed using an Agilent 8890A GC (Agilent Technologies, Inc., Santa Clara, CA, USA) equipped with a 60 m × 0.25 mm × 0.25 µm Rxi-5Sil-MS capillary column (Restek, Inc., France), coupled to a triple quadrupole Agilent 7000D MS (Agilent Technologies, Inc., Santa Clara, CA, USA).The temperature program for the GC oven started at 80 °C (1.5 min hold), then continued with 40 °C/min to 200 °C (18 min hold) and lastly 5 °C/min to 305 °C (no hold).The inlet temperature was 280 °C.The injection volume was 1 µl in pulsed-splitless mode.The carrier gas was helium with a 1.5 mL/min flow rate.The temperature of the GC-MS transfer line was 310 °C.The ion source was heated to 250 °C.The mass spectrometer was operating in multiple reaction monitoring (MRM) mode with nitrogen as collision gas with a flow of 1.5 mL/min.Compound quantification was done with MassHunter Workstation 10.1 software (Agilent Technologies, Inc., Santa Clara, CA, USA) with an external calibration curve, with a linear range of 1 ng/ml to 1 µg/ml.Phthalates p-terphenyl was used as the internal standard and added after the final volume reduction.
Phthalates were analyzed using an Agilent 7890A GC (Agilent Technologies, Inc., Santa Clara, CA, USA) equipped with a 30 m × 0.25 mm × 0.25 µm Rxi-5Sil-MS capillary column (Restek, Inc., France), coupled to a tandem mass spectrometer Agilent 7000B MS/MS (Agilent Technologies, Inc., Santa Clara, CA, USA).The temperature program of the GC oven started at 80 °C (3 min hold) and then increased at a rate of 7 °C/min until reaching 320 °C (5 min hold).The inlet temperature was set at 280 °C.The injected sample volume was 1 µl in splitless mode.The carrier gas used was helium with a 1.5 mL/min flow rate.The transfer line and ion source temperatures were set at 280 °C.Electron impact ionization (EI) was used, and the mass spectrometer was operating in selected ion monitoring (SIM) mode, with nitrogen as the collision gas at a flow rate of 1.5 mL/min.Compound quantification was done using MassHunter Workstation 10.1 software (Agilent Technologies, Inc., Santa Clara, CA, USA) with an external calibration curve, with a linear range of 10 ng/ml to 10 µg/ml.CUPs CUPs were analyzed using an Agilent 1290 Series Gradient HPLC System (Agilent Technologies, Inc., Santa Clara, CA, USA) equipped with a Luna C-18 endcapped (4 μm) size 100 x 2 mm (Phenomenex, CA, USA) equipped with a Phenomenex SecurityGuard C18 size 4 × 2 mm guard column (Phenomenex, CA, USA), coupled to a SCIEX QTrap 5500+ MS (ABSciex, CA, USA) with ESI source.The column was held at 30 °C in a column oven.The injection volume was 5 µl.Separation was achieved using an aqueous solution of 0.1% formic acid (mobile phase A) and MeOH with 0.1% formic acid (mobile phase B) at a flow rate of 0.25 mL/min.The method duration was 11.5 minutes.Ionization was monitored in positive mode using electrospray ionization (ESI+) with the following parameters: 5500 V, a heated source at 400 °C, Ion Source Gas 1 (40 psi), Ion Source Gas 2 (30 psi), and curtain gas (15 psi).An eight-point, calibration curve of native CUP standards was used for quantification and results were processed in Analyst (SCIEX, CA, USA).PFAS PFAS were analyzed using an Agilent 1290 Series Gradient HPLC System (Agilent Technologies, Inc., Santa Clara, CA, USA) equipped with a SYNERGI 4μ Fusion Max-RP 80Ä size 100 mm × 2 mm column (Phenomenex, CA, USA) together with a Phenomenex SecurityGuard C18 size 4 × 2 mm guard column (Phenomenex, CA, USA), coupled to a QTrap 5500+ MS (SCIEX, CA, USA) with ESI source.The column was held at 30 °C in a column oven.The injection volume was 10 µl.Separation was achieved using a 5 mM aqueous solution of ammonium acetate (55:45) (mobile phase A) and MeOH (mobile phase B) at a flow rate of 0.4 mL/min.The method duration was 11 minutes.Ionization was monitored in negative mode using electrospray ionization (ESI-) with the following parameters: 4500 V, a heated source at 450 °C, Ion Source Gas 1 (50 psi), Ion Source Gas 2 (30 psi), and curtain gas (15 psi).An eleven-point, calibration curve of native PFAS standards was used for quantification and results were processed in Analyst (SCIEX, CA, USA).
Text S2 Instrumental analysis at NILU laboratories PAHs D10-biphenyl, D10-fluoranthene and D12-perylene were used as the internal standard and added after the final volume reduction.PAHs were analyzed using an Agilent 5977A/7890B GC/LRMS (Agilent Technologies, Inc., Santa Clara, CA, USA) equipped with a standard split/splitless injector.A Select PAH size 30 m × 0.25 mm × 0.15 μm capillary column (Agilent Technologies, Inc., Santa Clara, CA, USA) was used.The temperature program of the GC oven started at 50 °C (1,5 min hold), then the temperature was increased in the first ramp at a rate of 5° C/m to 230 °C (0 min hold ), then in the second ramp at a rate of 10 °C/min to 280 °C (0 min hold), and then in the third ramp at a rate of 5 °C/min to 310 °C (10 min hold).The injection volume was 1 μL in splitless mode.The inlet temperature was 300 °C.Helium was used as carrier gas with a 1.9 mL/min flow rate.Electron ionization (EI) SIM mode with a source temperature of 300 °C was used.Molecular ions were used in PAH quantification.Substituted PAHs D10-Biphenyl, D10-fluoranthene and D12-perylene were used as the internal standard and added after the final volume reduction.Substituted PAHs were analyzed using an Agilent 7890B/7200 GC/qTOF (Agilent Technologies, Inc., Santa Clara, CA, USA) equipped with a PTV inlet.An HP-5ms Ultra Inert size 15 m × 0.25 mm × 0.25μm capillary column (Agilent Technologies, Inc., Santa Clara, CA, USA) was used.The temperature program of the GC oven started at 55 °C (2 min hold), then the temperature was increased in the first ramp at a rate of 45 °C/min to 150 °C (0 min hold), then in the second ramp at a rate of 5 °C/min to 230°C (0 min hold), and then in the third ramp at a rate of 15 °C/min to 325 °C (3 min hold).The PVT injection volume was 1 μL.The inlet temperature was 300 °C.Helium was used as carrier gas with a flow rate of 1.4 mL/min.ECNI scan mode with a source temperature of 150 °C was used.Molecular ions were used in nitro-oxy-PAH quantification.
PBDEs and NFRs 1,2,3,4-tetrachloronaphthalene was used as the internal standard and added after the final volume reduction.PBDEs and BFRs were analyzed using an Agilent 7890A GC (Agilent Technologies, Inc., Santa Clara, CA, USA) with a 7683B Agilent autosampler (Agilent Technologies, Inc., Santa Clara, CA, USA) equipped with an RTX-1614 size 15 m × 0.25 mm × 0.10 µm capillary column (Restek, Inc., France), coupled to a Micromass Autospec M mass spectrometer (Waters Corporation, Milford, MA, USA).The temperature program of the GC oven started at 45 °C (2.5 min hold), then the temperature was increased in the first ramp at a rate of 22 °C/min until reaching 220 °C (0 min hold) and then in the second ramp at a rate of 7 °C/min until reaching 320 °C (0 min hold).The PTV injection program started at 45 °C (0.35 min hold) then the temperature was increased by 250 °C/min until reaching 320 °C (24 min hold).The injected sample volume was 1 µl.Helium was used as carrier gas with a 1.7 ml/min flow rate.
CPs and dechloranes 1,2,3,4-tetrachloronaphthalene was used as the internal standard and added after final volume reduction.CPs and dechloranes were analyzed using an Agilent 7200B GC-qToF (Agilent Technologies, Inc., Santa Clara, CA, USA) in ECNI mode equipped with an HP-5ms Ultra Inert size 15 m × 0.25 mm × 0.25µm capillary column (Agilent Technologies, Inc., Santa Clara, CA, USA).The temperature program of the GC oven started at 55 °C (2 min hold) and then the temperature was increased in the first ramp at a rate of 70 °C/min until reaching 200 °C (1 min hold), then in the second ramp at the rate of 20 °C/min until reaching 280 °C (1 min hold), then in the third ramp at the rate of 5 °C/min until reaching 300 °C (0 min hold) and finally in the fourth ramp at the rate of 70 °C/min until reaching 320 °C (1 min hold).The PTV injection program started at 60 °C (0.35 min hold) then the temperature was increased by 500 °C/min until reaching 320 °C (1 min hold), then cooled down at a rate of 500 °C/min until reaching 60 °C (0 min hold).The transfer line temperature (GC-MS connection) was set at 280 °C.The injected sample volume was 0.1 µl.Helium was used as carrier gas with a 1.

Table S1 :
Surrogate standards (added prior to extraction) and internal standards (added prior to injection, marked in italic in the table) used in analysis at NILU Laboratories.

Table S2 :
Surrogate standards (added prior to extraction) and internal standards (added prior to injection, marked in italic in the table) used in analysis at RECETOX Laboratories.

Table S3 :
List of compounds included in the method development and relevant physical-chemical properties.Physical-chemical properties were obtained from EPA CompTox Dashboard.
2 ml/min flow rate.HBCD, D18-β-HBCD and D18-γ-HBCD were used as the internal standard and added after final volume reduction.HBCDs were analyzed using a liquid chromatograph Vanquish UHPLC System (Thermo Fisher Scientific Inc., Waltham, MA, USA) equipped with a capillary column Acquity UPLC HSS T3 size 3.0 mm × 150 mm, 1.8 µm (Waters Corporation, Milford, MA, USA), which was held at 40 °C in a column oven, coupled to a Q Exactive Plus Orbitrap mass spectrometer (Thermo Fisher Scientific Inc., Waltham, MA, USA).BADGE was used as the internal standard and added after final volume reduction.BADGE/BFDGE were analyzed using a liquid chromatograph Vanquish UHPLC System (Thermo Fisher Scientific Inc., Waltham, MA, USA) equipped with a capillary column Acquity UPLC HSS T3 size 3.0 mm × 150 mm, 1.8 µm (Waters Corporation, Milford, MA, USA), which was held at 40 °C in a column oven, coupled to a Q Exactive Plus Orbitrap mass spectrometer (Thermo Fisher Scientific Inc., Waltham, MA, USA).The injection volume was 4 µl for samples and 3 µl for standards.The mobile phase start gradient was MeOH: Type 1 Water (40:60) + 2mM Ammoniumacetate, increased to 100% MeOH in 8 minutes (2 minutes hold time) at a flow rate of 500 µl/min.The method duration was 10 minutes.The method for MS was Top5 peaks with the following parameters: positive polarity, 200 -650 m/z scan range and resolution of 70,000.A resolution of 17,500 was used in the subsequent MS² stage with an inclusion list and stepped collision energy (CE) fragmentation of 30.

Table S4 :
Instrument detection and quantification limits (IDL, IQL) and blank concentrations for Phase 3 extractions.

Table S5 :
Percentage recoveries from Phase 1 analysis, SUPRAS 1-5 are different SUPRAS (see Table 1), and A and B are replicates.

Table S6 :
Matrix effect from Phase 1 analysis calculated for SUPRAS 1.The matrix effect was calculated as 100-[(average response of analyte in matrix eluent/average response of analyte in standard solution)*100].

Table S8 :
Comparison of SRM 2585 certified/literature values (ng/g) with those obtained by SUPRAS extraction and "conventional" hex:ace and MeOH extractions.
Figure S1: Comparison of SRM 2585 certified/literature values (ng/g) with those obtained by SUPRAS extraction and "conventional" extractions.PHTHs and NFRs are displayed on logarithmic scale.