New approaches for the analysis of dyestuffs in historical textiles by liquid chromatography and desorption electrospray ionisation (DESI) mass spectrometry: applications to Renaissance embroideries and late nineteenth century textiles

The analysis of historical dyestuffs plays a central role in the understanding of the socioeconomic context of textile production while also informing strategies for the display and preservation of museum objects. Chapter 1 presents a summary of the most important dyes and fibres together with analytical challenges unique to the field of historical dye analysis. The main analytical techniques used in the field, including both invasive and non-invasive as well as destructive and non-destructive techniques are also discussed. Emphasis is given to the need for the development of more reliable, efficient, and ideally minimally or non-invasive analytical approaches for historical dye analysis. The material and methods used are shown in Chapter 2 while the high-throughput, small-scale sample preparation method and short analytical time UHPLC-PDA method developed are described in Chapter 3. The entire workflow from extraction, filtration, drying and reconstitution strategies as well as the UHPLC-PDA separation were evaluated using nine flavonoid and anthraquinone chromophores. The method was applied to a set of 85 reference samples covering 12 dye sources and a case study of the wedding tartan of Flora MacDonald from the West Highland Museum. In Chapter 4, the workflow is applied to important examples of Scottish and English embroideries dated from the mid-16th to early 18th centuries housed at National Museums Scotland (NMS). The significance of the collection is contextualised through discussion of embroidery in Tudor and Stuart Scotland and England. The analysis of 26 objects spanning from professional clothing to domestic furnishings show that similar materials was accessible to all types of embroiderers. The range of dyestuffs identified; from locally sourced lichens to imported cochineal demonstrate that embroidery was already by the 16th century, a craft dependent on global trade. The study also showcases the efficiency of the method applied to over 250 samples. The development of non-invasive, minimally destructive desorption electrospray ionisation (DESI) mass spectrometry for the field of dye analysis is presented in Chapter 5. The design and construction of the source are outlined, alongside optimisation of geometric parameters using silk and wool samples dyed with rhodamine B. The feasibility of the application of DESI-MS to textile analysis was evaluated on natural and early synthetic dye references and successfully applied to the study of late 19th century historical samples

An optimised small-scale sample preparation workflow for historical dye analysis using UHPLC-PDA applied to Scottish and English Renaissance embroidery

A sample preparation workflow for historical dye analysis based on 96 well plates and filtration by centrifugation was developed. It requires less sample and the introduced error is decreased, making it useful for culturally important objects. A sample preparation workflow for historical dye analysis requiring less sample has been developed. Samples as small as 0.01 ± 0.005 mg have been successfully analysed and high percentage recoveries (>85%), more automation and shorter preparation time have been achieved using filtration by centrifugation and only one manual transfer. The optimised workflow based on 96 well plates together with the shorter UHPLC method developed makes dye analysis data collection faster from unprocessed sample to result, facilitating the creation of larger datasets and application of chemometric approaches. The method was evaluated on 85 samples from 12 dye sources (RSD < 5.1%, = 5) as well as 22 samples from a 17 century embroidered stomacher from the National Museums Scotland (NMS) collection

Willingness to volunteer in a Phase I/II HIV vaccine trial: a study among police officers in Dar es Salaam, Tanzania

Background: As HIV infection continues to be a public health problem, development of an effective preventive HIV vaccine is a priority. For the ultimate development of an AIDS vaccine, clinical trials are being conducted throughout the world. However, the process of developing the vaccine does not only depend on identification of suitable trial candidates, but also requires knowledge of incentives to participate in the community where the trial is being conducted. Therefore, the studies presented in this thesis are components of a HIV/AIDS and HIV vaccine trial project in Dar es Salaam, Tanzania to address motivations and deterrents of participating in an HIV vaccine trial. Aim: To examine the motivations and deterrents for participating in preventive HIV vaccine trials. Methods: Data were collected from participants and volunteers who were considered for participation or participated in a phase I/II HIV vaccine trial. Four studies with different designs were conducted. In Study I, a semi-structured interview administered questionnaire was used to assess willingness to volunteer for a phase I/II HIV vaccine trial. A convenience sample of 329 individuals from the police force cohort was recruited for the study in 2005-2006. In Study II, focus group discussions were conducted to explore factors that would influence participation in an HIV vaccine trial among members of the police force in 2006-2007. In Study III, face-to-face interviews were used to identify reasons for declining to enrol in an HIV vaccine trial among those who agreed to enrol at the start and were randomized for the trial in 2007-2009. In Study IV, we used focus group discussions to evaluate the experiences of those who participated in the phase I/II trial in 2009. Results: Willingness to volunteer for an HIV vaccine trial was associated with intention to tell others, positive outcome of the trial, personal decision and expectation of obtaining protection against HIV infection. Participation in an HIV vaccine trial would be negatively influenced by sexual partners, friends, family members, relatives or parents (significant others) and fear of vaccine side-effects. Personal fears and negative influences from significant others were the main reasons for declining to enrol in an HIV vaccine trial. Despite the negative comments from significant others, volunteers in the HIV vaccine trial managed to stay on until the end of the trial as a result of personal decision and trial-related interventions. Conclusion: Personal decision is both a motivation to participate in an HIV vaccine trial and a reason to stay on until the end of trial. On the contrary, significant others are the deterrents to participation in the HIV vaccine trial and the reason for declining to enrol in the HIV vaccine trial. Awareness of these issues before trial implementation may help to maximize resource use and enhance retention of those who volunteer in the HIV vaccine trials

Balancing collective responsibility, individual opportunities and risks: a qualitative study on how police officers reason around volunteering in an HIV vaccine trial in Dar es Salaam, Tanzania

Results from HIV vaccine trials on potential volunteers will contribute to global efforts to develop an HIV vaccine. The purpose of this study among police officers in Dar es Salaam, Tanzania, was to explore the underlying reasons that induce people to enrol in an HIV vaccine trial.\ud We conducted discussions with eight focus groups, containing a total of 66 police officers. The information collected was analyzed using interpretive description. The results showed that participants were motivated to participate in the trial by altruism, and that the participants experienced some concerns about their participation. They stated that altruism in the fight against HIV infection was the main reason for enrolling in the trial. However, young participants were seriously concerned about a possible loss of close relationships if they enrolled in the HIV vaccine trial. Both men and women feared the effect of the trial on their reproductive biology, and they feared interference with pregnancy norms. They were unsure about risks such as the risks of acquiring HIV infection and of suffering physical harm, and they were unsure of the intentions of the researchers conducting the trial. Further, enrolling in the trial required medical examination, and this led some participants to fear that unknown diseases would be revealed. Other participants, however, saw an opportunity to obtain free health services.\ud We have shown that specific fears are important concerns when recruiting volunteers to an HIV vaccine trial. More knowledge is needed to determine participants' views and to ensure that they understand the conduct of the trial and the reasons it is being carried out

Dyes in History and Archaeology 41

This Special Issue features contributions from the conference DHA41. Dyes in History and Archaeology (DHA) is an annual international conference that focuses on the academic discussion of dyes and organic pigments which have been used in the past. Every year since 1982, this meeting has drawn together conservators; curators; (technical) art historians; craftspeople; artists; independent scholars; and scientists and academics from museums, universities, research centers and other public or private institutions. Their common interest is to delve deeply into the history, production, application, and properties of organic colorants, as well as their analytical characterization and identification, often in textile objects, but also in other substrates as well as painted surfaces. In the autumn of 2022, the 41st DHA conference was hosted by the Swedish National Heritage Board in Visby. This was the first DHA conference held in Scandinavia, and it attracted over 50 in-person participants, 70% of whom travelled from other countries to attend this conference on the beautiful island of Gotland. During the morning sessions of the three-day conference, the attendants in Visby had the opportunity to participate in workshops, tours, and activities. The afternoons were reserved for the scientific conference sessions, with all lectures broadcasted live and over 650 online participants. The book of abstracts is published on the DiVA portal (Digitala Vetenskapliga Arkivet), and many of the presented posters are available for download from the conference program. We are very grateful to the authors of the following 16 articles in this Special Issue for submitting their manuscripts and allowing us to put together a publication that presents the fascinating breadth of research into Dyes in History and Archaeology. For more information about the future meetings of the Dyes in History and Archaeology group, see https://www.dyesinhistoryandarchaeology.com

Development and Application of Desorption Electrospray Ionization Mass Spectrometry for Historical Dye Analysis

Primary data files for the data presented in upcoming publication E. Sandström, C. Vettorazzo, C.L. Mackay, L.G. Troalen and A.N. Hulme. 'Development and Application of Desorption Electrospray Ionization Mass Spectrometry for Historical Dye Analysis.' Analytical Chemistry (in submission)

Development and Application of Desorption Electrospray Ionization Mass Spectrometry for Historical Dye Analysis

A desorption electrospray ionization (DESI) source was built and attached to a Bruker 7T SolariX FT-ICR-MS for the in situ analysis of 14 early synthetic dyestuffs. Optimization using silk and wool cloths dyed with rhodamine B concluded that when using a commercial electrospray emitter (part number: 0601815, Bruker Daltonik), a nebulizing gas (N2) pressure of 3.9 bar and a sprayer voltage of 4.5 kV (positive ionization mode) or 4.2 kV (negative ionization mode), a solvent system of 3:1 v/v ACN:H2O, and a sprayer incident angle, α, of 35° gave the highest signal-to-noise ratios on both silk and wool for the samples investigated. The system was applied to modern early synthetic dye references on silk and wool as well as historical samples from the 1893 edition of Adolf Lehne’s Tabellarische Übersicht über die künstliche organischen Farbstoffe und ihre Anwendung in Färberei und Zeugdruck [Tabular overview of the synthetic organic dyestuffs and their use in dyeing and printing]. The successful analysis of six chemically different dye families in both negative and positive modes showed the presence of known degradation products and byproducts arising from the original synthetic processes in the historical samples. This study demonstrates the applicability and potential of DESI-MS to the field of historical dye analysis

Historical Textile Dye Analysis Using DESI-MS

Desorption electrospray ionization mass spectrometry (DESI-MS) is an ambient mass spectrometry technique that shows great potential for the analysis of fragile heritage objects in situ. This article focuses on the application of a recently built DESI source to characterize natural dyestuffs in historical textiles and a presentation of initial imaging experiments. Optimization of the instrumental settings, geometrical parameters, and solvent system on the DESI-MS analysis was conducted on rhodamine B samples. Some variables, including an increased flow rate, a narrower range of optimized geometrical variables and a solvent system without additives, were applicable to both early synthetic and natural dyes. Direct dye turmeric (Curcuma longa L.) could be reliably analyzed on both silk and wool, as could anthraquinone standards without mordanting. These preliminary results suggest that the dye application process (direct, mordant, vat) has a large impact on the ionization efficiency of DESI-MS. Imaging trials highlighted the suitability of DESI-MS for the analysis of patterned textiles that are difficult to sample, such as calico fabrics, or other currently inaccessible objects

The Influence of Community Members on Participation by Youth in an HIV Vaccine Trial in Tanzania.

In sub-Saharan Africa, the burden of HIV is high among young people and it is of the utmost importance that they be recruited into vaccination trials. Since community members influence the willingness of young people to participate in the vaccination trials, ascertaining their opinions is essential to overcoming barriers to such participation. Here, in seven focus group discussions we explored the views of 44 community members identified as someone they felt close by youth in Tanzania. The transcripts of these discussions were examined using content analysis. Our participants expressed that community members would be directly involved in the decisions of young people about whether or not to participate in an HIV vaccine trial. In general, they felt that community members would provide social support for youth during the trial and perceived that youth might have misconceptions concerning the vaccine and trial process. The participants pointed out structural factors such as substance use, poverty, stigma and unemployment that are barriers to participation. In conclusion, involvement of community members could be an integral part of the recruitment and retention of young people in HIV vaccine trials in Tanzania

Historical textile dye analysis using DESI-MS

Desorption electrospray ionization mass spectrometry (DESI-MS) is an ambient mass spectrometry technique that shows great potential for the analysis of fragile heritage objects in situ. This article focuses on the application of a recently built DESI source to characterize natural dyestuffs in historical textiles and a presentation of initial imaging experiments. Optimization of the instrumental settings, geometrical parameters, and solvent system of the DESI-MS analysis were conducted on rhodamine B samples. Some variables, including an increased flow rate, a narrower range of optimized geometrical variables and a solvent system without additives, were applicable to both early synthetic and natural dyes. Direct dye turmeric (Curcuma longa L.) could be reliably analyzed on both silk and wool, as could anthraquinone standards without mordanting. These preliminary results suggest that the dye application process (direct, mordant, vat) has a large impact on the ionization efficiency of DESI-MS. Imaging trials highlighted the future suitability of DESI-MS for the analysis of patterned textiles that are difficult to sample, such as calico fabrics, or other currently inaccessible objects. The dataset is related to the paper Sandström, E., Vettorazzo, C., Logan Mackay, C., Troalen, L.G. and Hulme, A.N. (2023). "Historical Textile Dye Analysis Using DESI-MS", Heritage 6(5), 4042-4053; https://doi.org/10.3390/heritage6050212