Sensing Application — Ultrasensitive levofloxacin electrochemical biosensor based on semiconducting covalent organic framework/poly-L-cysteine/triangular Ag nanoplates modified glassy carbon electrode

6 measurement groups · 36 results

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

cyclic voltammetry

Voltammetry

TABQ-CHHO-COF/Poly-L-Cys/Tri-AgNP/GCE · Electrode

LEV oxidation in 0.1 M PBS at pH 5.5; Fig. 3 caption reports 100 uM LEV at 100 mV/s.

Geometry: three-electrode system with SCE reference and Pt counter electrode
Context: target composite sensor compared with controls
Measurement source: p006 · Electrochemical behavior of LEV on the different modified electrodes · Fig. 3

Property	Reported value	Normalised value	Uncertainty	Origin and quality	Source
oxidation current enhancement versus bare GCEMarked as a best value within this paper	2.38 times than bare GCE	—	—	Text Exact Reported	p006 · Electrochemical behavior of LEV on the different modified electrodes · Fig. 3
LEV electrochemical oxidation behaviour	only an oxidation peak appeared; irreversible oxidation	—	—	Qualitative Qualitative	p006 · Electrochemical behavior of LEV on the different modified electrodes · Fig. 3
peak current density enhancement versus bare GCEMarked as a best value within this paper	1.08 times than bare GCE	—	—	Text Exact Reported	p006 · Electrochemical behavior of LEV on the different modified electrodes · Fig. 3

differential pulse voltammetry

Voltammetry

TABQ-CHHO-COF/Poly-L-Cys/Tri-AgNP/GCE · Electrode

DPV in 0.1 M PBS at pH 5.5 for LEV concentrations from 0.05 to 600 uM; scan rate 100 mV/s reported in Fig. 4 caption.

Geometry: three-electrode system with SCE reference and Pt counter electrode
Context: target composite sensor
Measurement source: p007-p008 · Determination of LEV · Fig. 4; Table 1

Property	Reported value	Normalised value	Uncertainty	Origin and quality	Source
high-concentration calibration slope	(0.0240+-0.0005) c + 2.12; R2 = 0.997; 60-600 uM	—	+-0.0005	Text Exact Reported	p007 · Determination of LEV · Fig. 4b
overall LEV linear rangeMarked as a best value within this paper	0.05-600 uM	—	—	Text Range	p001 · Abstract
LEV detection limitMarked as a best value within this paper	0.00610 uM (S/N = 3)	—	—	Text Exact Reported	p007 · Determination of LEV · Fig. 4; Table 1
low-concentration calibration slopeMarked as a best value within this paper	(0.0547+-0.0015) c + 0.00420; R2 = 0.993; 0.05-60 uM	—	+-0.0015	Text Exact Reported	p007 · Determination of LEV · Fig. 4b
LEV DPV oxidation peak potential	0.92 V	—	—	Text Exact Reported	p007 · Determination of LEV · Fig. 4a
Table 1 linear range for this workMarked as a best value within this paper	0.05-600 uM	—	—	Table Range	p008 · Determination of LEV · Table 1

DPV/CV optimisation

Voltammetry

TABQ-CHHO-COF/Poly-L-Cys/Tri-AgNP/GCE · Electrode

Optimisation of COF loading, Tri-AgNP loading, poly-L-cysteine cycles, pH, and scan rate for LEV response.

Geometry: three-electrode system with SCE reference and Pt counter electrode
Context: target composite sensor
Measurement source: p006-p007 · Optimization of the experiment conditions · Figs. S3-S5

Property	Reported value	Normalised value	Uncertainty	Origin and quality	Source
calculated electron number for LEV oxidation	n = 2.05	—	—	Calculated From Reported Approximate	p007 · Optimization of the experiment conditions · Scheme 2
optimal COF suspension drop-coating amountMarked as a best value within this paper	5 uL	—	—	Text Exact Reported	p003-p004 · S3. Optimization of the experiment conditions · Fig. S3a
optimal pH for LEV determinationMarked as a best value within this paper	pH = 5.5	—	—	Text Exact Reported	p006 · Optimization of the experiment conditions · Fig. S4
optimal electropolymerisation cyclesMarked as a best value within this paper	25 cycles	—	—	Text Exact Reported	p003-p004 · S3. Optimization of the experiment conditions · Fig. S3c
optimal Tri-AgNP suspension drop-coating amountMarked as a best value within this paper	4 uL	—	—	Text Exact Reported	p003-p004 · S3. Optimization of the experiment conditions · Fig. S3b
proton/electron ratio from pH dependence	m/n = 0.77 approximately 1	—	—	Calculated From Reported Approximate	p006 · Optimization of the experiment conditions · Fig. S4c
Epa-pH regression slope	Epa = 1.14 - 0.0454 pH, R2 = 0.994	—	—	Text Exact Reported	p006 · Optimization of the experiment conditions · Fig. S4c
Epa versus ln(scan rate) regression slope	Epa = 0.0251 lnv (mV/s) + 0.822; R2 = 0.995	—	—	Text Exact Reported	p007 · Optimization of the experiment conditions · Fig. S5c
Ipa versus scan rate regression slope	Ipa = 0.0340 v (mV/s) + 1.48; R2 = 0.991	—	—	Text Exact Reported	p006 · Optimization of the experiment conditions · Fig. S5b
linear scan-rate range for oxidation peak current density	40-180 mV/s	—	—	Text Range	p006 · Optimization of the experiment conditions · Fig. S5a-b

standard addition DPV in human serum and urine

Voltammetry

TABQ-CHHO-COF/Poly-L-Cys/Tri-AgNP/GCE · Electrode

Serum centrifuged and diluted in 0.1 M PBS pH 5.5; urine filtered with 0.22 um membrane and diluted; spiked with 50.0 or 100 uM LEV.

Geometry: three-electrode DPV test
Context: target composite sensor
Measurement source: p008 · Real sample analysis · Table 2

Property	Reported value	Normalised value	Uncertainty	Origin and quality	Source
human serum found concentration after 100 uM spike	Add 100 uM; found 104 uM; recovery 104%; RSD 3.8%	—	RSD 3.8%	Table Exact Reported	p008 · Real sample analysis · Table 2
human serum found concentration after 50 uM spike	Add 50.0 uM; found 52.0 uM; recovery 104%; RSD 4.1%	—	RSD 4.1%	Table Exact Reported	p008 · Real sample analysis · Table 2
human urine found concentration after 100 uM spike	Add 100 uM; found 97.1 uM; recovery 97.1%; RSD 2.9%	—	RSD 2.9%	Table Exact Reported	p008 · Real sample analysis · Table 2
human urine found concentration after 50 uM spike	Add 50.0 uM; found 48.6 uM; recovery 97.2%; RSD 4.6%	—	RSD 4.6%	Table Exact Reported	p008 · Real sample analysis · Table 2

standard addition DPV in low-dilution human serum and urine

Voltammetry

TABQ-CHHO-COF/Poly-L-Cys/Tri-AgNP/GCE · Electrode

Human blood serum and urine samples treated according to Inorganic Chemistry 60 (2021) 6585-6599 and diluted 20 times; spiked with 50.0 or 100 uM LEV; n = 3.

Geometry: three-electrode DPV test
Context: target composite sensor
Measurement source: p010 · S7. Real sample analysis · Table S1

Property	Reported value	Normalised value	Uncertainty	Origin and quality	Source
low-dilution human serum found concentration after 100 uM spike	Add 100 uM; found 107 uM; recovery 107%; RSD 4.1%	—	RSD 4.1%	SI Table Exact Reported	p010 · S7. Real sample analysis · Table S1
low-dilution human serum found concentration after 50 uM spike	Add 50.0 uM; found 53.2 uM; recovery 106%; RSD 4.8%	—	RSD 4.8%	SI Table Exact Reported	p010 · S7. Real sample analysis · Table S1
low-dilution human urine found concentration after 100 uM spike	Add 100 uM; found 95.5 uM; recovery 95.5%; RSD 4.3%	—	RSD 4.3%	SI Table Exact Reported	p010 · S7. Real sample analysis · Table S1
low-dilution human urine found concentration after 50 uM spike	Add 50.0 uM; found 46.9 uM; recovery 93.8%; RSD 3.9%	—	RSD 3.9%	SI Table Exact Reported	p010 · S7. Real sample analysis · Table S1

DPV repeatability, reproducibility, stability and selectivity tests

Voltammetry

TABQ-CHHO-COF/Poly-L-Cys/Tri-AgNP/GCE · Electrode

Five separately fabricated electrodes; one electrode measured 10 times; once-daily DPV for 10 days; interferences tested against 60 uM LEV.

Context: target composite sensor
Measurement source: p008-p010 · S6. Repeatability, reproducibility, stability and selectivity · Fig. S8

Property	Reported value	Normalised value	Uncertainty	Origin and quality	Source
repeatability across five separately fabricated electrodes	RSD 3.85% for 60 uM LEV	—	—	Text Exact Reported	p008-p010 · S6. Repeatability, reproducibility, stability and selectivity · Fig. S8a
ten repeated determinations with one electrode	RSD 3.33% for 60 uM LEV	—	—	Text Exact Reported	p008-p010 · S6. Repeatability, reproducibility, stability and selectivity · Fig. S8b
organic antibiotic interference tolerance	10 times concentration; peak-current change below +-10%	—	—	Text Exact Reported	p008-p010 · S6. Repeatability, reproducibility, stability and selectivity · Fig. S8d
ascorbic acid interference concentration	ascorbic acid 57 uM; no interference for 60 uM LEV; peak-current change below +-10%	—	—	Text Exact Reported	p009 · S6. Repeatability, reproducibility, stability and selectivity · Fig. S8d
glucose interference concentration	glucose 7800 uM; no interference for 60 uM LEV; peak-current change below +-10%	—	—	Text Exact Reported	p009 · S6. Repeatability, reproducibility, stability and selectivity · Fig. S8d
inorganic interference tolerance	50 times concentration; peak-current change below +-10%	—	—	Text Exact Reported	p008-p010 · S6. Repeatability, reproducibility, stability and selectivity · Fig. S8d
interference peak-current change threshold	below +-10%	—	—	Text Exact Reported	p008-p010 · S6. Repeatability, reproducibility, stability and selectivity · Fig. S8d
uric acid interference concentration	uric acid 400 uM; no interference for 60 uM LEV; peak-current change below +-10%	—	—	Text Exact Reported	p009 · S6. Repeatability, reproducibility, stability and selectivity · Fig. S8d
DPV signal retained after 10 days	93.6% of original value	—	—	Text Exact Reported	p008-p010 · S6. Repeatability, reproducibility, stability and selectivity · Fig. S8c