ISO 20814:2019

Nanotechnologies — Testing the photocatalytic activity of nanoparticles for NADH oxidation

This document specifies a method for the measurement of the photocatalytic activity (PCA) of nanoparticles (NPs), suspended in an aqueous environment in physiologically relevant conditions, by measuring the ultraviolet (UV)-induced nicotine adenine dinucleotide hydrate (NADH) oxidation. The measurement is intended to assess the potential for the photo-toxicity of nanomaterials. The method is also applicable to NP aggregates and agglomerates.

Nanotechnologies — Test de l'activité photocatalytique des nanoparticules pour l'oxydation du NADH

General Information

• Status: Published
• Publication Date: 02-Dec-2019
• ICS: 07.120 - Nanotechnologies
• Technical Committee: ISO/TC 229 - Nanotechnologies
• Drafting Committee: ISO/TC 229 - Nanotechnologies
• Current Stage: 6060 - International Standard published
• Start Date: 03-Dec-2019
• Due Date: 06-Nov-2019
• Completion Date: 03-Dec-2019

Standards Content (Sample)

INTERNATIONAL ISO
STANDARD 20814
First edition
2019-12
Nanotechnologies — Testing
the photocatalytic activity of
nanoparticles for NADH oxidation
Nanotechnologies — Test de l'activité photocatalytique des
nanoparticules pour l'oxydation du NADH
Reference number
ISO 20814:2019(E)
©
ISO 2019

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ISO 20814:2019(E)

COPYRIGHT PROTECTED DOCUMENT
© ISO 2019
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
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Published in Switzerland
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ISO 20814:2019(E)

Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms, definitions, symbols and abbreviated terms . 1
3.1 Terms and definitions . 1
3.2 Symbols and abbreviated terms. 2
4 Description of the test method . 3
5 Reagents and apparatus . 3
5.1 Reagents. 3
5.2 Apparatus . 4
6 Measurement procedure . 4
6.1 Measurement of NP suspension basic properties . 4
6.1.1 UV-Vis absorption spectrum measurement. 4
6.1.2 NP suspension stability measurement . 5
6.2 UV trans-illuminator light intensity calibration based on 2NB actinometry . 5
6.3 Measurement of NADH solution fluorescence intensity . 6
6.3.1 NADH photo-oxidation rate measurement at various NP concentrations . 6
6.3.2 Calculation of NADH photo-oxidation rate at various NP concentrations . 7
7 Test report . 8
7.1 Information . 8
7.2 Report data format . 9
7.2.1 Correction factors C(i,j) obtained by actinometry (see 7.2) with λ(max,TI) . 9
7.2.2 Calibrated slope of NADH fluorescence decrease. 9
7.2.3 Plot of k versus NP concentration .10
app
7.2.4 NADH equivalent specific PCA .10
8 Precision .10
8.1 Repeatability .10
8.2 Reproducibility .10
Annex A (normative) Schematic diagram of 96-well positioning block .11
Annex B (informative) Sample calibration of UV trans-illuminator light intensity .12
Annex C (informative) Interlaboratory comparison study of TiO NP PCA .17
2
Bibliography .22
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ISO 20814:2019(E)

Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out
through ISO technical committees. Each member body interested in a subject for which a technical
committee has been established has the right to be represented on that committee. International
organizations, governmental and non-governmental, in liaison with ISO, also take part in the work.
ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of
electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www .iso .org/ directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see www .iso .org/ patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO’s adherence to the
World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT) see www .iso .org/
iso/ foreword .html.
This document was prepared by Technical Committee ISO/TC 229, Nanotechnologies.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www .iso .org/ members .html.
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ISO 20814:2019(E)

Introduction
Photocatalytic activity (PCA) is the measure of capacity of a material to promote a specific photochemical
reaction under defined conditions (as defined in ISO 20507:2014, 2.3.31). With the expanding use of
nanomaterials in various industries, the possible impacts on human health and the environment due to
the enhancement of detrimental chemical reactions in the presence of light (both natural and artificial)
is an ongoing concern. The absorption of a photon with sufficient energy generates an electron-hole
pair that can migrate to the nanoparticle (NP) surface and react with water and oxygen, thus forming
extremely reactive radicals and reactive oxygen species (ROS). Generation of the ROS by some wide-
bandgap materials, such as TiO , ZnO, WO , CeO , carbon nanotubes, quantum dots and some metal
2 3 2
NPs when illuminated by UV-VIS light, can cause oxidative stress, resulting in toxic effects in living
[5]
organisms . Therefore, measuring the nanomaterial PCA under physiological conditions allows for an
assessment of its photo-toxicity potency.
Existing standard test methods for particle and surface PCA measurement (see ISO 10676 and
ISO 10678) are not directly applicable to determine nanomaterial PCA leading to photo-toxicity, as
they require a large test volume and/or long measurement duration, while utilizing organic dyes as
indicators that are not biocompatible.
The in vitro NP PCA test for NADH oxidation is intended to evaluate the nanomaterial photo-toxicity
potency when exposed to an ultraviolet (UV) light.
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INTERNATIONAL STANDARD ISO 20814:2019(E)
Nanotechnologies — Testing the photocatalytic activity of
nanoparticles for NADH oxidation
1 Scope
This document specifies a method for the measurement of the photocatalytic activity (PCA) of
nanoparticles (NPs), suspended in an aqueous environment in physiologically relevant conditions, by
measuring the ultraviolet (UV)-induced nicotine adenine dinucleotide hydrate (NADH) oxidation.
The measurement is intended to assess the potential for the photo-toxicity of nanomaterials. The
method is also applicable to NP aggregates and agglomerates.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments) applies.
ISO/TS 80004-1, Nanotechnologies — Vocabulary — Part 1: Core terms
ISO/TS 80004-2, Nanotechnologies — Vocabulary — Part 2: Nano-objects
3 Terms, definitions, symbols and abbreviated terms
For the purposes of this document, the terms and definitions given in ISO/TS 80004-1, ISO/TS 80004-2
and the following apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at http:// www .electropedia .org/
3.1 Terms and definitions
3.1.1
actinometry
method to measure the number of photons integrally or per unit of time
3.1.2
catalytic activity
property of a component corresponding to the catalysed substance rate of conversion of a specified
chemical reaction, in a specified measurement system
[SOURCE: ISO 18153:2003, 3.2, modified — The notes have been deleted.]
3.1.3
oxidation
chemical reaction accompanying a gain of oxygen, loss of hydrogen of an organic substrate or loss of
one or more electrons from a molecular entity
3.1.4
NADH equivalent specific PCA
PCA measured as the NADH photo-oxidation (3.1.5) rate per unit weight of nanoparticles
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3.1.5
photo-oxidation
oxidation reactions induced by light
3.2 Symbols and abbreviated terms
DIW deionized water with ≥ 18 MΩ·cm resistivity
NADH nicotine adenine dinucleotide hydrate
NaOH sodium hydroxide
2NB 2-nitrobenzaldehyde
NP nanoparticle
PB phosphate buffer
PCA photocatalytic activity
ROS reactive oxygen species
TI trans-illuminator
TiO titanium dioxide
2
UV ultraviolet
UV-Vis ultraviolet and visible
A (i,j) phenolphthalein absorbance before exposure to trans-illuminator UV irradiation in
c
each well (i = B, C, D, E, F, G; j = 2, 3, 4, …, 10, 11)
A (i,j) phenolphthalein absorbance after exposure to trans-illuminator UV irradiation in each
e
well (i = B, C, D, E, F, G; j = 2, 3, 4, …, 10, 11)
ΔA(i,j) change in phenolphthalein absorbance after exposure to trans-illuminator UV
irradiation in each well (i = B, C, D, E, F, G; j = 2, 3, 4, …, 10, 11)
ΔA average change of phenolphthalein absorbance over all wells before and after UV
a
irradiation by using a UV trans-illuminator
C starting concentration of the NP suspension for a dilution series of test solutions;
0
the suspension absorbance at 310 nm or 365 nm (depending on the used UV
trans-illuminator) is 1,4 < A < 1,6
C(i,j) light intensity correction factor of each well, which accounts for the UV irradiation
intensity variation of the UV trans-illuminator at the location of each well
(i = B, C, D, E, F, G; j = 2, 3, 4, …, 8, 9)
I (i,j) NADH fluorescence intensity measured before UV irradiation in each well
F,0
(i = B, C, D, E, F, G; j = 2, 3, 4, …, 8, 9)
I (i,j) NADH fluorescence intensity measured following the UV irradiation of t duration by
F,t
using a UV trans-illuminator in each well (i = B, C, D, E, F, G; j = 2, 3, 4, …, 8, 9)
k (i,j) apparent NADH photo-oxidation rate in each well, expressed in μmol/min
app
(i = B, C, D, E, F, G; j = 2, 3, 4, …, 8, 9)
λ excitation wavelength used to record fluorescence in multiple well plate readers
exc
λ emission wavelength used to record fluorescence in multiple well plate readers
ems
A λ(max) maximum absorbance of NP suspension in a wavelength range from 300 nm to 800 nm
λ(max,TI) wavelength at which a UV trans-illuminator provides the maximum intensity of light
S(i,j) slope of the NADH fluorescence intensity versus the UV irradiation time in each well
(i = B, C, D, E, F, G; j = 2, 3, 4, …, 8, 9)
S (i,j) S(i,j) corrected for the trans-illuminator light intensity variation at each well
c
b slope of k versus NP concentration in the linear range, expressed in units
app
of mmol/min⋅g
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ISO 20814:2019(E)

4 Description of the test method
In this document, the PCA of NPs in an aqueous suspension is measured as the photo-oxidation rate of
NADH present in the NP suspension. By observing the NADH fluorescence intensity decrease before
and after successive irradiation with artificial UV light, the fraction of the oxidized NADH due to the
photocatalytic action of NPs can be measured. The photo-oxidation rate of NADH is determined at
several NP concentrations with a dilution series and the NP concentration range showing the linear
[6]
dependence of the photo-oxidation rate of NADH versus NP concentration is determined . The photo-
oxidation slope in this linear range provides the NADH photo-oxidation rate per unit of NP concentration
in the aqueous suspension. The multiplexed assay utilizes a 96-well plate, UV trans-illuminator and a
multiple-plate optical reader leading to a fast and accurate measurement. The 96-well platform allows
for a simultaneous measure of a range of NP concentrations and provides an option to compare with
reference NPs as positive and negative controls. It accounts for the spontaneous NADH photo-oxidation
under UV illumination in the absence of NPs and intrinsic NP fluorescence.
5 Reagents and apparatus
5.1 Reagents
5.1.1 NADH, β-Nicotinamideadenine dinucleotide, reduced disodium salt, CAS Number: 606-68-8.
a) Stock solution of NADH:
1) dissolve approximately 35 mg of NADH in 10 ml of 5 mmol/l phosphate buffer, pH = 8.
b) Working solutions of NADH:
1) dilute a stock solution of NADH by a factor of 20 into 5 mmol/l, pH = 8 phosphate buffer;
2) the resulting concentration of the working NADH solution will be about 250 μmol/l;
3) verify the working NADH concentration [NADH] by measuring the absorbance of the solution at
λ = 339 nm. If necessary, adjust the NADH concentration by diluting with a 5 mmol/l phosphate
buffer or by adding a NADH stock solution until absorbance A = 1,56 ± 0,05.
339
5.1.2 2-nitrobenzaldehyde (2NB), CAS Number: 552-89-6.
a) Prepare 50 ml 0,1 mol/l solution of 2NB by dissolving 0,756 g of the dry 2NB in 50 ml of 50/50 DIW/
ethyl alcohol (by volume).
b) Adjust the 0,1 mol/l 2NB solution to pH = 12 ± 0,2 by adding 0,03 mol/l NaOH.
5.1.3 Phenolphthalein, CAS Number: 77-09-8.
a) Prepare 20 ml of stock solution of phenolphthalein by dissolving 20 mg of dry phenolphthalein in
20 ml of 50/50 DIW/ethyl alcohol.
b) Add 100 μl of phenolphthalein stock [prepared in step a)] to a 50 ml 0,1 mol/l 2NB solution
(prepared as per 5.1.2). The solution acquires pink colour.
c) Store the solution in light-protected bottle (amber glass or wrapped in Al foil).
5.1.4 Phosphate buffer, sodium phosphate monobasic/dibasic solution for pH buffer of pH 8
(5 mmol/l PB at pH 8).
EXAMPLE The phosphate buffer is prepared as follows.
Step 1: Dissolve 1,261 g of disodium phosphate, heptahydrate (CAS Number: 7782-85-6) in 1 l of DIW.
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Step 2: Add 0,041 g of monosodium phosphate, monohydrate (CAS Number: 10049-21-5) to the solution prepared
in Step 1.
Step 3: Measure the solution pH, following the complete dissolution of salts.
5.1.5 NP suspension.
a) Prepare 50 ml of NP suspension in a 5 mmol/l phosphate buffer according to the recommended
dispersion protocol for the particular nanomaterial (e.g. Reference [7]).
b) Adjust the NP dispersion concentration C so that the highest absorbance reading of the
0
NP dispersion in a range of 300 nm to 800 nm is 1,4 < A < 1,6. Calculate the stock solution NP
concentration C (in mg/l) following the adjustment.
0
c) From the mass concentration of the prepared stock NP suspension, dilution factors for the
preparation of the target concentration of working suspensions can be calculated.
5.1.6 Ethyl alcohol, anhydrous, > 99,5 % pure, less than 0,005 % water. CAS Number: 64-17-5.
5.2 Apparatus
5.2.1 UV-Vis spectrophotometer, wavelength range: 190 nm to 800 nm, absorbance range: 0,1 to 3,0.
5.2.2 Cuvette for UV-Vis absorption measurement, quartz or optical glass, 1 cm optical path length.
5.2.3 96-well plate, [flat bottom surface transparent at λ(max,TI): T > 60 %], dark plastic sides
preferable.
5.2.4 Microplate absorbance and fluorescence reader, capable of absorbance and fluorescence
measurement in a range from 300 nm to 800 nm.
5.2.5 Multi-pipette loader, which has at least six channels with at least 300 μl channel capacity.
5.2.6 300 μl pipette tips, compatible with the multi-pipette loader.
5.2.7 UV trans-illuminator, 365 nm light source with a horizontal illumination area larger or equal to
the 96-well plate.
6 Measurement procedure
6.1 Measurement of NP suspension basic properties
6.1.1 UV-Vis absorption spectrum measurement
a) Measure the UV-VIS absorption spectrum of the NP suspension (see 5.1.5) in a range from 300 nm
to 800 nm in a 10 mm optical path-length quartz or optical glass spectrophotometer cuvette
against 5 mmol/l PB as reference.
NOTE Filling a standard 10 mm cuvette usually requires around 3 ml of sample.
Preferably, use the same cuvette for both the reference and the sample.
b) If the absorbance of suspension at λ(max) [A λ(max)] exceeds 1,6, dilute the suspension with a
phosphate buffer (5 mmol/l PB, pH = 8) until 1,4 < A λ(max) < 1,6. If it’s below 1,4, increase the NP
concentration accordingly.
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6.1.2 NP suspension stability measurement
NOTE This is required to ensure NPs stay suspended during the measurement duration.
a) Measure the baseline (reference absorbance) using 5 mmol/l PB, pH = 8,0.
b) Measure the UV-Vis absorption spectrum of the NP working suspension, with the concentration
adjusted in accordance with 6.1.1.
c) Wait for 20 min while maintaining the cuvette in the spectrophotometer, then re-measure the UV-
VIS absorption spectrum of the working suspension.
d) Compare the two spectra and verify that a change in the maximum absorbance is less than 5 % at
λ(max). The NP working suspension is not regarded as stable if absorbance at λ(max) decreases
more than 5 % over 20 min.
6.2 UV trans-illuminator light intensity calibration based on 2NB actinometry
a) Prepare a 50 ml 0,1 mol/l solution of 2NB, containing phenolphtalein in accordance with 5.1.2 and
5.1.3. Use an amber glass container to store the solution.
b) Fill each well of the 96-well plate with 300 μl of solution, as prepared in a).
c) Place the 96-well plate in the reader, programme it to shake the plate for 5 s, and measure and
record the absorbance at 540 nm – A (i,j).
c
WARNING — Observe that it is positioned at the same location and orientation as during the
NADH/NP UV exposure. Follow the directions in Annex A for the plate positioning.
d) Turn on the trans-illuminator [lambda = λ(max,TI)] and warm up for 30 min.
e) Position the 96-well plate on the trans-illuminator.
f) Expose the plate to UV light for 10 min.
g) After 10 min, turn off the trans-illuminator, and measure and record the absorbance at 540 nm
using the 96-well plate reader – A (i,j).
e
h) Subtract the absorbance values, recorded in step c), from the absorbance values recorded in step g)
for each well, as shown by Formula (1):
ΔA(i,j) = A (i,j) – A (i,j) (1)
e c
i) Calculate the average differential absorbance, as shown by Formula (2):
ΔA = ∑ΔA(i,j)  all 60 working wells/60 (2)
a
j) Calculate the light intensity correction factors for light intensity at each well, as shown by
Formula (3):
C(i,j) = ΔA /ΔA(i,j) (3)
a
k) The light intensity correction factors for individual wells will be multiplied by the slope of NADH
florescence decrease, calculated as shown by Formula (5) in 6.3.2.3.
A sample calibration of UV trans-illuminator light intensity is given in Annex B.
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6.3 Measurement of NADH solution fluorescence intensity
6.3.1 NADH photo-oxidation rate measurement at various NP concentrations
6.3.1.1 Prepare the 250 μmol/l NADH solution in accordance with 5.1.1.
6.3.1.2 Prepare the stock NP suspension (using the appropriate dispersion procedure, see 5.1.5)
C = 100 %. The absorbance at λ(max) (in a range from 300 nm to 800 nm) should be 1,4 < A < 1,6.
0
6.3.1.3 Prepare the dilution (by volume) series of NP suspension (each 2 ml using a phosphate buffer)
at concentrations (relative to C = 100 %). See 6.3.1.2: 100 %, 80 %, 60 %, 40 %, 20 %, 10 %, 8 %, 5 %.
0
6.3.1.4 Fill wells marked in white with 100 μl of 250 μmol/l NADH solution, as shown in Figure 1.
NOTE Wells marked in white contain 100 μl of 250 μmol/l NADH solution and: a buffer for col. 2; 100 μl NP
suspension at C for col. 3; 100 μl NP suspension at 80 % C for col. 4; 100 μl NP suspension at 60 % C for col. 5;
0 0 0
100 μl NP suspension at 40 % C for col. 6; 100 μl NP suspension at 20 % C for col. 7; 100 μl NP suspension at
0 0
10 % C for col. 8; 100 μl NP suspension at 8 % C for col. 9; 100 μl NP suspension at 5 % C for col. 10; 100 μl NP
0 0 0
suspension at C + 100 μl buffer (5 mmol/l PB, pH = 8) solution for col. 11.
0
Figure 1 — Schematic diagram of a 96-well plate for NADH photo-oxidation rate measurement
at various NP concentrations
6.3.1.5 Add 100 μl of the NP suspension dilution series and fill the wells as described below. Mix the
solutions in the individual wells by pipetting in and out at least three times.
— A1, B1, ⋅⋅⋅, G1, H1 (column): No use.
— A2, A3, ⋅⋅⋅, A10, A11 (row): No use.
— B2, C2, D2, E2, F2, G2: Blank buffer.
— B3, C3, D3, E3, F3, G3: NP suspension at C
0.
— B4, C4, D4, E4, F4, G4: NP suspension at 80 % of C
0.
— B5, C5, D5, E5, F5, G5: NP suspension at 60 % C
0.
— B6, C6, D6, E6, F6, G6: NP suspension at 40 % C
0.
— B7, C7, D7, E7, F7, G7: NP suspension at 20 % C
0.
— B8, C8, D8, E8, F8, G8: NP suspension at 10 % C
0.
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— B9, C9, D9, E9, F9, G9: NP suspension at 8 % C B10, C10, D10, E10, F10, G10:
0
NP suspension at 5 % C
0.
— B11, C11, D11, E11, F11, G11: 100 μl NP suspension at C + 100 μl buffer (5 mmol/l PB,
0
pH = 8) solution.
— A12, B12, ⋅⋅⋅, G12, H12 (column): No use.
— H2, H3, ⋅⋅⋅, H10, H11 (row): No use.
6.3.1.6 Measure and record the fluorescence intensity values of individual wells (λexc = 340 nm and
λems = 460 nm). The values shall be called IF,0(i,j), where i is the row number assigned as B to G, and j is
the column number assigned as 2 to 11.
6.3.1.7 Place the 96-well plate on the UV trans-illuminator and turn on the lamp for 1 min.
The UV-trans-illuminator should be switched on for 30 min prior to plate exposure.
Make sure that the plate is positioned at the same location and orientation during repetitive UV
exposure. See Annex A for a description of the plate positioner.
6.3.1.8 Measure and record the fluorescence intensity values of individual wells. The values shall be
called IF,t(i,j), where t is the exposure duration to UV.
6.3.1.9 Repeat the steps in 6.3.1.7 and 6.3.1.8 until the fluorescence intensities in wells B6, C6, D6, E6,
F6 and G6 decrease below 50 % of their initial values (prior to the UV exposure).
6.3.2 Calculation of NADH photo-oxidation rate at various NP concentrations
6.3.2.1 Normalize the measured fluorescence intensities of individual wells, IF,t(i,j), as a function of UV
illumination time with IF,0(i,j) values as shown by Formula (4):
I (i,j) = I (i,j) / I (i,j) (4)
F,t,N F,t F,0
where
i is B to G;
j is 2 to 11.
6.3.2.2 Plot the normalized intensities of each well, I (i,j), as a function of the illumination time
F,t,N
and perform a linear regression in the range where the intensity decrease is linearly dependent on the
illumination time.
6.3.2.3 Calculate the slope of each well, S(i,j), and multiply by C(i,j), obtained from the procedure in 6.2,
to get UV illumination intensity calibrated slopes as shown by Formula (5):
S (i,j) = S(i,j) × C(i,j) (5)
C
6.3.2.4 Calculate the NADH photo-oxidation rate at each well, k (i,j), as shown by Formula (6), using
app
[NADH] value, obtained from the absorbance measurement as in 5.1.1:
k (i,j) = S (i,j) × [NADH] (6)
app C
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6.3.2.5 Calculate the column averages and standard deviations of the k values for each NP
app
concentration. Normalize k with respect to intrinsic NADH photo-oxidation by calculating a ratio
app
k (i,j)/k (2,j), where k (2,j) is the value for NADH only (column 2 data). The average and the
app app app
standard deviations of k at a particular NP concentration can be calculated using a single column
app
reading.
Discard the data if the slope Sc(i,j) > 0. Report as k (i,j) = 0.
app
6.3.2.6 Plot the normalized k values versus NP concentrations, expressed in mg/l. An example of a
app
rate constant versus concentration plot is shown in Figure 2.
6.3.2.7 The slope of k versus NP concentration in the linear range (b) gives the NADH photo-
app
oxidation rate per unit weight of NP in units of mmol/min⋅g. This value can be termed as the “NADH
equivalent specific PCA” of NP.
Key
X NP, in mg/l
Y k , in μM/min
app
Figure 2 — NADH photo-oxidation rate versus NP concentration
7 Test report
7.1 Information
The test report shall include the following information:
— a reference to this document, i.e. determined in accordance with ISO 20814:2019;
— the name of the testing laboratory;
— full details concerning the sample (manufacturer’s name, manufacturing date, batch no., purity,
particle size, intended application, SDS);
— if used, full details concerning the negative control (manufacturer’s name, manufacturing date,
batch no., purity, particle size, SDS);
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— if use
...