1、PD ISO/TS 19590:2017 Nanotechnologies Size distribution and concentration of inorganic nanoparticles in aqueous media via single particle inductively coupled plasma mass spectrometry BSI Standards Publication WB11885_BSI_StandardCovs_2013_AW.indd 1 15/05/2013 15:06PD ISO/TS 19590:2017 PUBLISHED DOCU
2、MENT National foreword This Published Document is the UK implementation of ISO/TS 19590:2017. The UK participation in its preparation was entrusted to Technical Committee NTI/1, Nanotechnologies. A list of organizations represented on this committee can be obtained on request to its secretary. This
3、publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application. The British Standards Institution 2017. Published by BSI Standards Limited 2017 ISBN 978 0 580 90502 5 ICS 07.120 Compliance with a British Standard cannot confer im
4、munity from legal obligations. This British Standard was published under the authority of the Standards Policy and Strategy Committee on 31 March 2017. Amendments/corrigenda issued since publication Date Text affectedPD ISO/TS 19590:2017 ISO 2017 Nanotechnologies Size distribution and concentration
5、of inorganic nanoparticles in aqueous media via single particle inductively coupled plasma mass spectrometry Nanotechnologies - Distribution de taille et concentration de nanoparticules inorganiques en milieu aqueux par spectromtrie de masse plasma induit en mode particule unique TECHNICAL SPECIFICA
6、TION ISO/TS 19590 Reference number ISO/TS 19590:2017(E) First edition 2017-03PD ISO/TS 19590:2017ISO/TS 19590:2017(E)ii ISO 2017 All rights reserved COPYRIGHT PROTECTED DOCUMENT ISO 2017, Published in Switzerland All rights reserved. Unless otherwise specified, no part of this publication may be rep
7、roduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below or ISOs member body in the country of the request
8、er. ISO copyright office Ch. de Blandonnet 8 CP 401 CH-1214 Vernier, Geneva, Switzerland Tel. +41 22 749 01 11 Fax +41 22 749 09 47 copyrightiso.org www.iso.orgPD ISO/TS 19590:2017ISO/TS 19590:2017(E)Foreword iv Introduction v 1 Scope . 1 2 Normative references 1 3 T erms and definitions . 1 4 Abbre
9、viated terms 2 5 Conformance . 2 6 Procedure. 3 6.1 Principle 3 6.2 Apparatus and equipment 3 6.3 Chemicals, reference materials and reagents . 3 6.3.1 Chemicals . 3 6.3.2 Reference materials . 3 6.3.3 Reagents 4 6.4 Samples . 4 6.4.1 Amount of sample . 4 6.4.2 Sample dilution . 5 6.5 Instrumental s
10、ettings and performance check . 5 6.5.1 Settings of the ICP-MS system 5 6.5.2 Checking the performance of the ICP-MS system 5 6.6 Determination of the transport efficiency . 6 6.6.1 Determination of transport efficiency based on measured particle frequency 6 6.6.2 Determination of transport efficien
11、cy based on measured particle size 7 6.7 Determination of the linearity of response 8 6.8 Determination of the blank level . 8 6.9 Analysis of aqueous suspension . 8 6.10 Data conversion 9 7 Results . 9 7.1 Calculations 9 7.1.1 Calculation of the transport efficiency .10 7.1.2 Calculation of the ICP
12、-MS response 10 7.1.3 Calculation of particle concentration and size 10 7.1.4 Calculation of the particle concentration detection limit 11 7.1.5 Calculation of the particle size detection limit12 7.1.6 Calculation of ionic concentration .13 7.2 Performance criteria .13 7.2.1 Transport efficiency .13
13、 7.2.2 Linearity of the calibration curve .13 7.2.3 Blank samples .13 7.2.4 Number of detected particles 13 8 Test report 13 Annex A (informative) Calculation spreadsheet15 Bibliography .19 ISO 2017 All rights reserved iii Contents PagePD ISO/TS 19590:2017ISO/TS 19590:2017(E) Foreword ISO (the Inter
14、national 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
15、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 st
16、andardization. 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 acco
17、rdance 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. De
18、tails 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
19、 an endorsement. For an explanation on the voluntary nature of standards, the meaning of ISO specific terms and expressions related to conformity assessment, as well as information about ISOs adherence to the World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT) see the
20、following URL: w w w . i s o .org/ iso/ foreword .html. This document was prepared by ISO/TC 229, Nanotechnologies.iv ISO 2017 All rights reservedPD ISO/TS 19590:2017ISO/TS 19590:2017(E) Introduction This document was developed in response to the worldwide demand of suitable methods for the detectio
21、n and characterization of nanoparticles in food and consumer products. Products based on nanotechnology or containing engineered nanoparticles are already in use and beginning to impact the food-associated industries and markets. As a consequence, direct and indirect consumer exposure to engineered
22、nanoparticles (in addition to natural nanoparticles) becomes more likely. The detection of engineered nanoparticles in food, in samples from toxicology and in exposure studies therefore becomes an essential part in understanding the potential benefits, as well as the potential risks, of the applicat
23、ion of nanoparticles. Single particle inductively coupled plasma mass spectrometry (spICP-MS) is a method capable of detecting single nanoparticles at very low concentrations. The aqueous sample is introduced continuously into a standard ICP-MS system that is set to acquire data with a high time res
24、olution (i.e. a short dwell time). Following nebulization, a fraction of the nanoparticles enters the plasma where they are atomized and the individual atoms ionized. For every particle atomized, a cloud of ions results. This cloud of ions is sampled by the mass spectrometer and since the ion densit
25、y in this cloud is high, the signal pulse is high compared to the background (or baseline) signal if a high time resolution is used. A typical run time is 30 s to 200 s and is called a “time scan.” The mass spectrometer can be tuned to measure any specific element, but due to the high time resolutio
26、n, typically only one m/z value will be monitored during a run (with the current instruments). The number of pulses detected per second is directly proportional to the number of nanoparticles in the aqueous suspension that is being measured. To calculate concentrations, the transport efficiency has
27、to be determined first using a reference nanoparticle. The intensity of the pulse and the pulse area are directly proportional to the mass of the measured element in a nanoparticle, and thereby to the nanoparticles diameter to the third power (i.e. assuming a spherical geometry for the nanoparticle)
28、. This means that for any increase of a particles diameter, the response will increase to the third power and therefore a proper validation of the response for each size range of each composition of nanoparticle is required. Calibration is best performed using a reference nanoparticle material; howe
29、ver, such materials are often not available. Therefore, calibration in this procedure is performed using ionic standard solutions of the measured element under the same analytical condition. The data can be processed by commercially available software or it can be imported in a custom spreadsheet pr
30、ogram to calculate the number and mass concentration, the size (the spherical equivalent diameter) and the corresponding number-based size distribution of the nanoparticles. In addition, mass concentrations of ions present in the same sample can be determined from the same data. The interested reade
31、r can consult References 1 to 4 for further information. ISO 2017 All rights reserved vPD ISO/TS 19590:2017PD ISO/TS 19590:2017Nanotechnologies Size distribution and concentration of inorganic nanoparticles in aqueous media via single particle inductively coupled plasma mass spectrometry 1 Scope Thi
32、s document specifies a method for the detection of nanoparticles in aqueous suspensions and characterization of the particle number and particle mass concentration and the number-based size distribution using ICP-MS in a time-resolved mode to determine the mass of individual nanoparticles and ionic
33、concentrations. The method is applicable for the determination of the size of inorganic nanoparticles (e.g. metal and metal oxides like Au, Ag, TiO 2 , BVO 4 , etc.), with size ranges of 10 nm to 100 nm (and larger particles up to 1 000 nm to 2 000 nm) in aqueous suspensions. Metal compounds other t
34、han oxides (e.g. sulfides, etc.), metal composites or coated particles with a metal core can be determined if the chemical composition and density are known. Particle number concentrations that can be determined in aqueous suspensions range from 10 6particles/L to 10 9particles/L which corresponds t
35、o mass concentrations in the range of approximately 1 ng/L to 1 000 ng/L (for 60 nm Au particles). Actual numbers depend on the type of mass spectrometer used and the type of nanoparticle analysed. In addition to the particle concentrations, ionic concentrations in the suspension can also be determi
36、ned. Limits of detection are comparable with standard ICP-MS measurements. Note that nanoparticles with sizes smaller than the particle size detection limit of the spICP-MS method may be quantified as ionic. The method proposed in this document is not applicable for the detection and characterizatio
37、n of organic or carbon-based nanoparticles like encapsulates, fullerenes and carbon nanotubes (CNT). In addition, it is not applicable for elements other than carbon and that are difficult to determine with ICP- MS. Reference 5 gives an overview of elements that can be detected and the minimum parti
38、cle sizes that can be determined with spICP-MS. 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 late
39、st edition of the referenced document (including any amendments) applies. ISO/TS 80004-1, Nanotechnologies Vocabulary Part 1: Core terms 3 T erms a nd definiti ons For the purposes of this document, the terms and definitions given in ISO/TS 80004-1 and the following apply. ISO and IEC maintain termi
40、nological databases for use in standardization at the following addresses: IEC Electropedia: available at h t t p :/ www .electropedia .org/ ISO Online browsing platform: available at h t t p :/ www .iso .org/ obp 3.1 nanoparticle nano-object with all three external dimensions in the nanoscale SOURC
41、E: ISO/TS 80004-2:2015, modified TECHNICAL SPECIFICATION ISO/TS 19590:2017(E) ISO 2017 All rights reserved 1PD ISO/TS 19590:2017ISO/TS 19590:2017(E) 3.2 aqueous suspension particle suspension whose suspending phase is composed of water 3.3 inductively coupled plasma mass spectrometry ICP-MS analytic
42、al technique comprising a sample introduction system, an inductively coupled plasma source for ionization of the analytes, a plasma/vacuum interface and a mass spectrometer comprising an ion focusing, separation and detection system 3.4 dwell time time during which the ICP-MS detector collects and i
43、ntegrates pulses Note 1 to entry: Following integration, the total count number per dwell time is registered as one data point, expressed in counts, or counts per second. 3.5 t r a n s p or t ef f ic ienc y p a r t i c l e t r a n s p o r t e f f i c i e n c y ne bu l i z at ion e f f ic ie nc y rat
44、io of the number of particles or mass of solution entering the plasma to the number of particles or mass of solution aspirated to the nebulizer 3.6 particle number concentration number of particles divided by the volume of a suspension, e.g. particles/L 3.7 particle mass concentration total mass of
45、the particles divided by the volume of a sample, e.g. ng/L 3.8 number-based particle size distribution list of values that defines the relative amount by numbers of particles present according to size 4 Abbreviated terms spICP-MS single particle inductively coupled plasma mass spectrometry (for the
46、definition of ICP-MS, see 3.3 or ISO/TS 80004-6:2013, 4.22) 5 Conformance This method is restricted to aqueous suspensions of pure nanoparticles, aqueous extracts of materials or consumer products, aqueous digests of food or tissue samples, aqueous toxicological samples or environmental water sample
47、s. The applicability of the method for such samples should be evaluated by the user. Information about sample processing of non-aqueous samples can be found in the literature. Aqueous environmental samples are filtrated and diluted 6 , food and toxicological samples are chemically or enzymatically d
48、igested and diluted 78 . However, to relate particle number or mass concentrations in aqueous suspensions to the concentrations in the original sample information on extraction, efficiency and matrix effects are required. Additional validation by the user is required.2 ISO 2017 All rights reservedPD
49、 ISO/TS 19590:2017ISO/TS 19590:2017(E) 6 Procedure 6.1 Principle When nanoparticles are introduced into an ICP-MS system, they produce a plume of analyte ions. The plumes corresponding to individual nanoparticles can be detected as a signal spike in the mass spectrometer if a high time resolution is used. Using dwell times of 10 ms and an appropriate dilution of the nanoparticle suspension allows the detection of individual nanoparticles, hence the name “single particle”-ICP-MS. Dilution is often required to avoid violation