Analytical StrategySiiri Bienz Masha Naumenko

26.11.2019

Work of arts

Former organic materials (like wood, leather, feathers)

Treated with biocides(inorganic and organic)to preserve them from biological decay

Introduction

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DangerDamage to other objects

Damage to the storage building

Damage to the object itselfHazard for the employees

Hazard for the visitors

Danger

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Process overview of a contaminated object

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ContaminationArt object Analysis Risk assessment Clean object

Decontamination

Background Field of work

Inorganic Biocides

Fluoride- and Fluorosilicate

Arsenic compounds Chromium compounds Mercury(II) chloride

skin irritation, nausea,

abdominal-painheadaches,

nausea, vomiting, carcinogenic

trigger chronic skin irritation, inflammation

visual and motor impairment, nerve

inflammation

-water-soluble-saline nature-low vapour pressure-reduced leaching (chromium fixation)

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https://doi.org/10.1016/j.culher.2012.01.015

Organic Biocides

PCP Lindane DDT Permethrin (R=H) Cypermethrin (R=CN)

Aldrin

Mw 266.34 290.83 354.49 391.29 416.3 364.90

Vapor Pressure, mmHg

(at 25 °C)

1.1⋅10-4 9.4⋅10-4 3⋅10-7 2.15⋅10-8 3.1⋅10-9 (20 °C) 7.5⋅10-5

liver, kidneys, blood, lungs,

nervous system,

immune system

nervous system

endocrine disruptor

convulsion,hyperthermia

irritation to skin and

eyes

liver, kidneys, nervous system,

convulsion

5

Example

Contaminated Object

Decontamination procedure development: washing with water, washing agents, decontamination by means of supercritical CO2 etc

DDT Lindane

Suitable techniques for quantitative and qualitative analysis for the wood preservatives and efficiency of the decontamination process

- expensive - time-consuming- destructive- low spatial resolution

+ virtually non-destructive+ single analysis takes only few

seconds+ simultaneous information on a

large number of different chemical elements

(micro-spot analysis)

XRF (μ-XRF)GC/MS Analysis

Schmidt, Birgit & Pentzien, Simone & Conradi, Andrea & Krüger, Jörg & Roth, Constanze & Beier, Oliver & Hartmann, Annett & Grünler, Bernd. (2017). Decontamination of biocidal loaded wooden artworks by means of laser and plasma processing. 241-251. 6

Analytical question

Requirements Nice-to-have

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Non-invasive

Portable

Sensitive

Quantification

Fast

Structural Analysis

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μ-XRF

Androulakis, Ioannis. (2017). An introduction to Computed Tomography for Coronary Artery Calcium Scoring

8

μ-XRF

Typical XRF

11L. Bonizzoni, A. Galli, G. Poldin and M. Milazzo, (2006). In situ non-invasive EDXRF analysis to reconstruct stratigraphy and thickness of Renaissance pictorial multilayers,(36), 55-61.

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STATIONARY MOBILE

detailed information about the distribution of the elements on the surface of the samples

FASTER

STATISTICALLY SATISFYING

μ-XRF

μ-XRF

Typical XRF spectrum of pinewoodcontaminated with wood preservatives

The concentrations of wood preservatives were measured by GC/MS

Jens Bartoll, Achim Unger, Karsten Püschner & Heike Stege (2003) Micro-XRF Investigations of Chlorine-Containing Wood Preservatives in Art Objects, Studies in Conservation, 48:3, 195-202

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μ-XRF

LIMITATIONSMISINTERPRETATIONS

not possible to discriminate between different kinds of chlorine-containing substances (need reference method)

-> Elemental analysis

high amount of measurements due to inhomogeneous distribution of preservatives on the wooden surface

incorrect determination of XRF intensities (uneven surfaces and and an imperfect positioning of the measurement head (for the large sub-areas))

Overestimation of the degree of contamination (chlorine and wood preservatives)

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Passive Sampling

CollectingMedium

Sampled Medium

CHEMICAL POTENTIAL DIFFERENCE

FICK’S LAWS J = - dC/dx

(M/t) = D⋅A⋅(Cma - Cms)/LmPERMEATION

CO

NC

ENTR

ATIO

NDISTANCE

MEMBRANE

SAMPLE

SAMPLER

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15Fabiana Portoni, Josep Grau-Bové, Matija Strlič (2019) Application of a non-invasive , non-destructive technique to quantify naphtalene emissions rate from museum objects, Heritage Science, 7:58

Passive Sampling

Passive Sampling

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PDMS (Polydimethylsiloxane)

Gerstel Twister™

TD unit GC unit MS unit

Passive Sampling

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TD-GC-MSPassive Sampling Quantitative and Qualitative

DDT

Caroline Raeppel, Brice m. Appenzeller,Maurice Millet, (2015), Determination of seven pyrethroids biocides and their synergist in indoor air by thermal-desorption gas chromatography/mass spectrometry after sampling on Tenax TA® passive tubes, Talanta, 131, 309-314

Permethrin

LIMITATIONSADVANTAGES

long sampling time

difficult to measure non-volatile species

strongly depends on humidity, T, membrane geometry

easy to perform

many samples simultaneously

non-invasive

Passive Sampling

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Alternative approaches

IMMOVABLE OBJECTS

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Alternative techniques

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XRD

NON-INVASIVE ANALYSIS

RAMAN SPECTROSCOPY

FTIR IN REFLECTION MODE

VISIBLE LIGHT IMAGING

FLUORESCENCE IMAGING

DART-MS

Raman Spectroscopy

[(1 − x)PbCrO4·xPbO]

(K2O·4ZnCrO4·3H2O)

Brunetti, B., Miliani, C., Rosi, F. et al. Top Curr Chem (Z) (2016) 374: 10. 21

Reflection-FTIR

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ATR crystal

IR beam To detector

Brunetti, B., Miliani, C., Rosi, F. et al. Top Curr Chem (Z) (2016) 374: 10.

M. Wörle, T. Lombardo et al.Studies in Conservation, (2019)

Sample

Fluorescencesample ~ 1 ug/mL

NILE RED

A sensitive fluorescence probe for DDT-type pesticides. Analytica Chimica Acta, 1998, (368): 77-82. Salan Hassoon, Israel Schechter.

methoxychlor DDT

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DART-MS

LC-MS and GC-MS are time-consuming and expensive

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Neutron-imaging method

25Eberhard H.Lehmann, David Mannes, Wood investigations by means of radiation transmission techniques, Journal of Cultural Heritage, 2012, S35-S43

Louvre: museum particle accelerator

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15 m below

Thank you for your attention!