N-glycyl-L-tyrosine

Adsorption / desorption

Link to relevant study record(s)

Reference

Endpoint:

adsorption / desorption: screening

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 121 (Estimation of the Adsorption Coefficient (Koc) on Soil and on Sewage Sludge using High Performance Liquid Chromatography (HPLC))

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of method:

HPLC estimation method

Radiolabelling:

no

Test temperature:

Column temperature: 35°C +/- 1°C

Details on study design: HPLC method:

EQUIPMENT
- Apparatus: Acquity UPLC system (Waters, Milford, MA, USA)
- Type, material and dimension of analytical (guard) column: Acquity UPLC HSS Cyano, 100 mm  2.1 mm i.d., dp = 1.8 µm (Waters)
- Detection system: Acquity UPLC TUV detector (Waters)

MOBILE PHASES
- Type:
55/45 (v/v) methanol/buffer pH 5
55/45 (v/v) methanol/buffer pH 7
55/45 (v/v) methanol/buffer pH 9
- Experiments with additives carried out on separate columns: no
- pH: 5,7 and 9
- Flow: 0.4 mL/min
- Injection volume: 5 µL



DETERMINATION OF DEAD TIME
- Method: by inert substances which are not retained by the column

REFERENCE SUBSTANCES
- Identity: Acetanilide (CAS 103-84-4), Monuron (CAS 150-68-5), 2,5-Dichloroaniline (CAS 95-82-9), Naphthalene (CAS 91-20-3), Benzoic acid phenylester (CAS 93-99-2), Fenthion (CAS 55-38-9 ), Phenanthrene (CAS 85-01-8), 4,4’-DDT (CAS 50-29-3)

DETERMINATION OF RETENTION TIMES
- Quantity of test substance introduced in the column: 10.0 mg/L

REPETITIONS
- Number of determinations: 2

EVALUATION
- Determination of the log Koc value:
pH9: The equation of the regression line was: log k’ = 0.301 x log Koc – 0.906 (r = 0.98, n = 16)
pH7: The equation of the regression line was: log k’ = 0.315 x log Koc – 0.839 (r = 0.98, n = 16)
pH5: The equation of the regression line was: log k’ = 0.310 x log Koc – 0.883 (r = 0.98, n = 16)

Sample No.:

#3

Type:

log Koc

Value:

< 1.26

pH:

9

Sample No.:

#2

Type:

log Koc

Value:

< 1.26

pH:

7

Sample No.:

#1

Type:

log Koc

Value:

< 1.26

pH:

5

Details on results (HPLC method):

- Retention times of reference substances used for calibration [min]:

pH9:
Formamide (t0) 0.750/0.754
Monuron 1.117/1.105
2,5-Dichloroaniline 1.231/1.218
Naphthalene 1.410/1.396
Benzoic acid phenylester 1.656/1.631
Fenthion 2.042/2.002
Phenanthrene 2.265/2.218
4,4’-DDT 4.748/4.576
- Average retention data for test substance pH 9 [min]: 0.513

pH7:
Formamide (t0) 0.730/0.729
Acetanilide 0.948/0.947
Monuron 1.159/1.161
2,5-Dichloroaniline 1.310/1.306
Naphthalene 1.531/1.523
Benzoic acid phenylester 1.808/1.807
Fenthion 2.346/2.341
Phenanthrene 2.620/2.607
4,4’-DDT 6.078/6.071
- Average retention data for test substance pH7 [min]: 0.549


pH5:
Formamide (t0) 0.758/0.758
Acetanilide 0.965/0.960
Monuron 1.150/1.153
2,5-Dichloroaniline 1.285/1.286
Naphthalene 1.479/1.474
Benzoic acid phenylester 1.738/1.733
Fenthion 2.240/2.235
Phenanthrene 2.460/2.445
4,4’-DDT 5.496/5.485
- Average retention data for test substance pH5 [min]: 0.763

Conclusions:

The log Koc values of the test material at the environmental relevant pH 5, pH 7 and pH 9 were <1.26

Description of key information

The HPLC method (OECD121) using soil-adsorption-reference data was applied for the determination of the adsorption coefficient (Koc) of N-Glycyl-L-tyrosine dihydrate measured as N-Glycyl-L-tyrosine. The log Koc value of the test material at pH 5, pH 7 and pH 9 were <1.26