Electrochemistry Application — Diazo-reaction based dual-mode colorimetric-electrochemical sensing of nitrite in pickled food

4 measurement groups · 24 results

Reported values remain attached to the sample, method, conditions, extraction quality and source location that produced them.

Cyclic voltammetry (CV) and Randles-Sevcik active-area calculation

Voltammetry

Cu-MOFs/EGP · Electrode

CV of Cu-MOFs/EGP in 5.0 mM K3[Fe(CN)6] and 0.1 M KCl at scan rates from 25 to 200 mV s-1.

Geometry: Cu-MOFs/EGP modified electrode.
Context: Composite electrode active-area estimate.
Measurement source: 5 · 3.3 Electrochemical sensing performance study · Fig. 4C-D

Property	Reported value	Normalised value	Uncertainty	Origin and quality	Source
Effective working area of Cu-MOFs/EGP	1.4 cm2	—	—	Text Exact Reported	5 · 3.3 Electrochemical sensing performance study · Fig. 4D
CV scan-rate upper bound	200 mV s-1	0.2 V s-1	—	Caption Exact Reported	5 · Figure caption · Fig. 4C
CV scan-rate lower bound	25 mV s-1	0.025 V s-1	—	Caption Exact Reported	5 · Figure caption · Fig. 4C
Geometric electrode area used for active-area comparison	0.5 cm x 1.5 cm	—	—	Calculated From Reported Exact Reported	5 · 3.3 Electrochemical sensing performance study

Differential pulse voltammetry (DPV)

Voltammetry

Cu-MOFs/EGP · Electrode

DPV in 0.1 M acetate buffer, pH 3.5, containing 1.0 mM TMB; potential range 0 V to +1.1 V.

Geometry: Three-electrode system using graphite paper or modified electrode as working electrode, Pt wire counter electrode and Ag/AgCl reference electrode.
Context: Composite working electrode compared with EGP control.
Measurement source: 3-5 · 2.6 and 3.3 · Fig. 4A-B

Property	Reported value	Normalised value	Uncertainty	Origin and quality	Source
DPV potential range upper limit	0 V to +1.1 V	—	—	Text Exact Reported	3 · 2.6 Electrochemical sensing of nitrite
Nitrite oxidation peak potential used for ratio	about 0.84 V	—	—	Text Approximate	5 · 3.3 Electrochemical sensing performance study · Fig. 4B
TMB oxidation peak potential used for ratio	0.38 V	—	—	Text Exact Reported	5 · 3.3 Electrochemical sensing performance study · Fig. 4B

Ratiometric DPV nitrite sensing using iNO2-/iTMB

Voltammetry

Cu-MOFs/EGP · Electrode

DPV curves of Cu-MOFs/EGP-TMB system with nitrite concentrations 6.7e-7, 1.0e-6, 5.0e-5, 1.0e-4, 1.5e-4 and 2.0e-4 mol L-1.

Geometry: Cu-MOFs/EGP working electrode in three-electrode cell.
Context: Composite sensing platform.
Measurement source: 5-6 · 3.4 The analytical performances of the dual-mode sensor · Fig. 5C-D

Property	Reported value	Normalised value	Uncertainty	Origin and quality	Source
Electrochemical linear range lower boundMarked as a best value within this paper	6.2 x 10-7 mol L-1	0.62 umol L-1	—	Text Exact Reported	6 · 3.4 The analytical performances of the dual-mode sensor · Fig. 5D
Electrochemical linear range upper boundMarked as a best value within this paper	2.0 x 10-4 mol L-1	200 umol L-1	—	Text Exact Reported	6 · 3.4 The analytical performances of the dual-mode sensor · Fig. 5D
Electrochemical nitrite LODMarked as a best value within this paper	5.4 x 10-7 mol L-1	0.54 umol L-1	S/N = 3	Text Exact Reported	6 · 3.4 The analytical performances of the dual-mode sensor · Fig. 5D
Electrochemical calibration R2	R2 = 0.993	—	—	Text Exact Reported	6 · 3.4 The analytical performances of the dual-mode sensor · Fig. 5D
Electrochemical calibration slope	iNO2-/iTMB = 3.9 x 10-3 cNO2- + 2.5 x 10-2	—	—	Text Exact Reported	6 · 3.4 The analytical performances of the dual-mode sensor · Fig. 5D

Electrochemical nitrite recovery in real food samples

Pickled-food nitrite test system using Cu-MOFs/EGP · Unknown

Pretreated food samples analysed by electrochemical mode with standard additions of 0, 25 and 50 umol L-1 nitrite.

Geometry: Cu-MOFs/EGP sensor.
Context: Application test of composite sensor.
Measurement source: 6 · 3.5 Analysis of real samples · Table 1

Property	Reported value	Normalised value	Uncertainty	Origin and quality	Source
Cantonese sausage found nitrite by electrochemical mode, added 0 umol L-1	5.54 umol L-1	0.0000055399999999999995 mol L-1	RSD NA	Table Exact Reported	6 · Table 1 · Table 1
Cantonese sausage found nitrite by electrochemical mode, added 25 umol L-1	24.90 umol L-1	0.0000249 mol L-1	RSD 1.5%	Table Exact Reported	6 · Table 1 · Table 1
Cantonese sausage found nitrite by electrochemical mode, added 50 umol L-1	51.94 umol L-1	0.000051939999999999994 mol L-1	RSD 1.7%	Table Exact Reported	6 · Table 1 · Table 1
Salted duck eggs found nitrite by electrochemical mode, added 0 umol L-1	ND	—	—	Table Qualitative	6 · Table 1 · Table 1
Salted duck eggs found nitrite by electrochemical mode, added 25 umol L-1	25.38 umol L-1	0.000025379999999999998 mol L-1	RSD 2.8%	Table Exact Reported	6 · Table 1 · Table 1
Salted duck eggs found nitrite by electrochemical mode, added 50 umol L-1	49.89 umol L-1	0.00004989 mol L-1	RSD 2.4%	Table Exact Reported	6 · Table 1 · Table 1
Ham sausage found nitrite by electrochemical mode, added 0 umol L-1	2.50 umol L-1	0.0000024999999999999998 mol L-1	RSD NA	Table Exact Reported	6 · Table 1 · Table 1
Ham sausage found nitrite by electrochemical mode, added 25 umol L-1	26.36 umol L-1	0.00002636 mol L-1	RSD 0.42%	Table Exact Reported	6 · Table 1 · Table 1
Ham sausage found nitrite by electrochemical mode, added 50 umol L-1	50.18 umol L-1	0.00005018 mol L-1	RSD 2.4%	Table Exact Reported	6 · Table 1 · Table 1
Pickled vegetables found nitrite by electrochemical mode, added 0 umol L-1	ND	—	—	Table Qualitative	6 · Table 1 · Table 1
Pickled vegetables found nitrite by electrochemical mode, added 25 umol L-1	24.30 umol L-1	0.0000243 mol L-1	RSD 2.0%	Table Exact Reported	6 · Table 1 · Table 1
Pickled vegetables found nitrite by electrochemical mode, added 50 umol L-1	48.33 umol L-1	0.00004832999999999999 mol L-1	RSD 2.4%	Table Exact Reported	6 · Table 1 · Table 1