Histidine

Density

Link to relevant study record(s)

Reference

Endpoint:

density

Remarks:

density

Type of information:

experimental study

Adequacy of study:

key study

Study period:

29.06 - 16.07.2015

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: The study is recently performed according to OECD and GLP. The study is well documented and conducted.

Qualifier:

according to guideline

Guideline:

OECD Guideline 109 (Density of Liquids and Solids)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method A.3 (Relative Density)

Deviations:

no

GLP compliance:

yes

Type of method:

pycnometer method

Specific details on test material used for the study:

Batch no.: P816P001
Expiry date: 03-01-2019
Storage: room temperature (20+/-5°C), away from light and humidity

Key result

Type:

density

Density:

1.449 g/cm³

Temp.:

20 °C

Remarks on result:

other: +/- 0.0003

Density ρ was calculated following the below equation:

ρ_test = [(m₄ - m₁)/(m₃ - m₁) - (m₅ - m₄)] * ρ_verd

with: ρ_verd = density of replacement liquid in g/cm³

which can be calculated as follows:

ρ_verd= (m₃ - m₁)/(m₂ -m₁) * ρ_water

with:

ρ_test = density of solid test item in g/cm³

ρ_verd= density of replacement liquid in g/cm³

m₁ = mass of empty pycnometer in g

m₂ = mass of pycnometer with water in g

m₃ = mass of pycnometer with replacement liquid in g

m₄ = mass of pycnometer with solid test item in g

m₅ = mass of pycnometer with replacement liquid and test item in g

The error was calculated following the below equation:

∆ρ = [(2 * ∆m * 100%) / (m₄- m₁)] + [(4 * ∆m * 100%) / (m₃– m₁) – (m₅- m₄)] + [2 * ∆m * 100%) / (m₃- m₁)] + [(2 * ∆m * 100%) / (m₂- m₁)]

with:

∆ρ = relative error of the measured density

∆m = absolute error of single weighing

Single determinations:

Determination	Density (g/cm^3)	Error of determination (g/cm^3)
1	1.4475	0.0003
2	1.4294	0.0003
3	1.4505	0.0003

Note: the duplicate determination (exp 1 and 2) showed unusual variation. Therefore, a third determination was undertaken.

As the third determination confirmed the result of the first determination, experiments 1 and 3 were used for evaluation.

Conclusions:

The density of L-isoleucine is 1.4490 g/cm3 at 20°C.

Executive summary:

In the current study the density of L-Isoleucine was determined according to OECD test guideline 109. The study was GLP. Using the pycnometer method, the density of L-Isoleucine was determined to be 1.4490 ± 0.0003 g/cm³at 20.0 ± 0.4°C.

The standard deviation was 0.0021 g/cm³, showing a good correlation of the two determinations. Therefore, the study is considered valid.

Description of key information

The density of L-isoleucine is 1.4490 g/cm3 at 20°C.

Key value for chemical safety assessment

Relative density at 20C:

1.449