Characteristics

DTMP

DTEP

DTBP

AP₁

AP₂

AP₃

AP₁

AP₂

AP₃

AP₁

AP₂

AP₃

Color

Red

Red

Red

Red

Red

Red

Red

Red

Red

λ_max

525

520

516

530

528

520

534

530

525

pH range

2.5 - 8.5

2.3 - 8.4

2.2 - 8.3

2.3 - 8.3

2.2 - 8.2

2.0 - 8.1

2.6 - 8.8

2.5 - 8.5

2.2 - 8.4

Optimum pH range

4.6 - 5.8

4.5 - 5.5

4.3 - 5.4

4.4 - 5.3

4.3 - 5.2

4.1 - 5.1

4.8 - 5.9

4.6 - 5.8

4.5 - 5.5

Ε × 10⁴ (L∙mol⁻¹∙cm⁻¹)

5.08

4.85

4.60

5.20

5.08

4.92

5.35

5.25

5.12

Degree of extraction (%)

98.7

98.5

98.4

98.7

98.6

98.5

98.7

98.6

98.5

Working range/µg cm⁻³

2 - 100

2 - 90

2 - 90

2 - 110

2 - 100

2 - 100

2 - 120

2 - 110

2 - 110

lg k_e

6.5

6.4

6.4

6.3

6.3

6.2

6.3

6.3

6.2

Stability constant (β)

10.35

10.15

10.06

10.26

10.10

9.95

10.45

10.23

10.18

lgK_ex

12.84

12.75

12.66

12.75

12.64

12.58

12.95

12.84

12.75