To optimize our project, we engaged with several stakeholders involved in our project. Talking to them, helped us further shape our project and come up with the most effective design we possibly could. Here we describe our journey and the interviews that helped us develop our sensor.


The value-sensitive design was an excellent place to start creating the product with the most impact. To find out more about the problem of GHB spiking and the opinion of the stakeholders on our product, it was also essential to talk to them. We talked to the stakeholders we had initially identified during our value-sensitive design. While talking with them we identified and were referred to new stakeholders which increased our findings. We made drastic changes to our product and its proposed implementation based on their input. We also discovered the greater necessity for an immediate on-site GHB test. It could be used by hospitals, law enforcement, and as a forensic tool in addition to preventing spikes. First, we show and explain all the interactions we have had with our stakeholders in our interactive timeline. Then we describe our findings on the problem and the solution. In Figure 1 a summary of the interactions with our stakeholders is shown.

Overview integrated HP
Figure 1. Overview integrated human practices. Initially, through stories from victims of GHB spiking we came up with the idea of a GHB sensor. Afterward, we identified the problem and recieved input from the target audience and nightlife establishments. With the help of healthcare facilities and law enforcement we identified more applications of our sensor. Lastly we talked to 5 safety institutions to ensure a safe product would be developed. With all the information gathered we could start designing a product which was at the end reviewed by victims of GHB spiking.

Interactive timeline

We created an interactive timeline to summarize our interactions with our stakeholders. Interviews constituted the majority of the communication, along with emails and questionnaires. Additionally, we show how the design altered as a result of interactions with stakeholders at each stage of the project. To read about our findings, click on the images of the stakeholders.


We first spoke with a variety of stakeholders via interviews to obtain a deeper understanding of the problem of GHB spiking. Only after we had identified the full extent of the problem we could design the desired solution.

Region of interest

To get a better understanding of the problem we first had to determine the region of interest in which we were going to conduct the research. We focussed on Western Europe, namely the United Kingdom, the Netherlands, France, and Belgium, as the amount of suspected spiking incidences grew the most there, nevertheless, their very well organized healthcare system [4][5][6] . As an iGEM team based in the Netherlands, we chose to conduct the research mainly there. The initial definition of the target audience for our sensor included individuals who frequent nightclubs, festivals, concerts, pubs, or house parties. Obviously, this is a sizable audience, but we selected it since these are the locations where people claim to have been spiked the most frequently.

Lack of data

In our initial discussions with our stakeholders, we learned that a significant underlying issue underlying GHB spikes is a lack of data. The media and individual accounts on the frequency of spiking and the proven incidents of spiking differ significantly from each other [1] . A large fraction of people in Western Europe claim to have either experienced having their drink spiked or to have known someone who has. According to a sexism-free-night survey conducted in Europe, 7.8% of the approximately 4500 respondents said they had been spiked "premeditated or with prior planning," such as when someone forced them to use a substance without their knowledge. Another research showed that in the UK, one in nine women and one in 17 men [4] says their drink has been spiked, and 28% of the interviewed people know someone whose drink has been spiked. In the Netherlands, NOS handed out a survey to 5000 people; 5% of people who filled out the survey said they had been spiked, and more than 50% of the women take the possibility of being spiked into account when going out. On the other hand experts’s research results indicate that GHB spiking is not often observed and proven [2][3] .

We initially spoke with Steven Biemans from the Trimbos Institute to determine the origin of the disparity. He informed us that GHB must be detected within the first 12 hours of use and that it may already be undetectable after three to six hours [4]. Additionally, he added that the window of detection is very small because GHB's effects last for only about 1.5 hours in the body. The signs of GHB spiking can also resemble alcohol intoxication quite closely. Finally, there is a general data shortage that needs to be addressed because people are frequently not believed to have been spiked. We also spoke with Amber Schaafsma, a Dutch first aid physician. She informed us that few hospitals perform GHB tests, which contributes to the shortage of data. Hospitals offer a rapid urine drug test, but it does not screen for GHB. To test for GHB an extensive test has to be done in the lab by a specialist. She told us this is usually not worth it due to the small timescale GHB can be detected and as the treatment between GHB and alcohol poisoning is the same. Leanneart Borra from the Dutch Forensic Institute (NFI) told us GHB is also hard to detect due to the endogenous presence in some drinks and your body. Cross-reactivity of sensors with ethanol also makes it harder to detect GHB. Ronald van Litsenburg, managing director of Event Medical Services, the company that provides medical services at significant events, was also the subject of our interviews. Following the cancellation of a festival in Belgium due to accusations of spiking, we sought to gain a deeper understanding of GHB spiking at festivals. According to the interviewee, no tests are performed at festivals since the course of treatment remains the same and because blood tests are inconvenient in these circumstances. Additionally, he claimed that festivals wouldn't purchase pricey single-use tests because they wouldn't be insured.

We spoke with Cornelis, a policeman from Delft who is active in monitoring the city's nightlife. We talked about the prevalence of GHB spikes in the Netherlands and the scarcity of information. According to him, there are three conceivable outcomes when someone is spiked:

  1. Someone is spiked, but they either don't know about it or don't bother to call the cops.
  2. Someone is spiked and calls the police, but for a number of reasons they don't want to go to the police station to register an official report.
  3. Someone who has been spiked wishes to report the incident to the police. This makes conducting an investigation exceedingly challenging. The scene is frequently dark, there are moving individuals, and there are flashing lights, so even if there is frequent camera footage, it might be difficult to determine if someone has been spiked.

Therefore, only a very small portion of the situations involving spikes yield a case that can be proved. We discovered where the absence of data originates from speaking with a range of stakeholders involved in the GHB spiking issue. We discovered that it results from a combination of GHB's difficult detection and a shortage of testing options.

Target audience

By conducting a focus group (10 people) amongst students (an age group that goes out very frequently), distributing a survey, and speaking with GHB spiking victims, we were able to obtain the target audience's perspective on the issue. We discovered from the focus group that the majority of participants don't feel safe in nighttime settings and that all participants were aware of the issue as a result of media coverage or personal experience. It was mentioned that their drinks are guarded at all times, they move in groups, consume the drink promptly, monitor the bartender, and avoid drinking in clubs as some precautions against GHB spiking. According to our survey (N=661), nearly 70% of people who go out consider the chance of getting spiked. Over 80% of these people make an effort to avoid spiking by taking the following actions:

  1. Not taking drinks from strangers.
  2. Not leaving their drink unattended.
  3. Putting their hand on top of their drink.


We talked to two victims of GHB spiking to get their input on the problem of GHB spiking. One of the victims got proof of being spiked. The other one did not. The victim without proof explained they suspected the bartender of spiking them. Because of this we researched and found more of these cases [5][6] . After the incident the victim was very cautious and was unhappy they didn’t have any proof. The victim with proof explained they suspected a stranger they met when going out spiked them. They did get proof of GHB spiking in the hospital and that helped explaining the situation to people. For the full stories of the victims see the timeline.

Nightlife’s side

In order to gain hospitality businesses’ perspective on the issue, we also wanted to speak with them. We spoke with Querine Hoejenbos, a representative of the Dutch hospitality industry working for the "Koninklijke Horeca" (KNH), a collective organization. She said that because businesses have no control over the issue, owners of nightlife establishments frequently also feel like victims. Jetti Steffers from a club in Rotterdam informed us that guests are subject to bag inspections for liquids. She claimed that because the drugs are so small and the clubs only conduct a minimal search, it is almost impossible to find people using drugs within the establishment. We distributed a survey to over 140 European nightclubs, but recieved little replies (N=13). This is probably due to the fact that clubs don't want to be involved with research on GHB spiking because of expected bad publicity.

Needle spiking

Needle spiking is a relatively new phenomenon where drugs are injected with a needle to spike people. Just like with drink spiking experts doubt to what extent it’s happening. The first needle spiking case was confirmed, but since then no other proved case was filed. We decided to ask experts from the Trimbos institute, Event medical services, a physician, the KNH, and the police. They told us they doubted if needle spiking is really a problem, as needle spiking would require a long injection time and is just not as efficient as drink spiking. Also GHB would be too viscous to be used [7] . The survey did suggest that a large percentage of our target audience was scared of needle spiking.


Besides gaining a better understanding of the problem of GHB spiking, the stakeholder interactions also influenced our proposed solution.

Electrical system

After deciding on making a GHB sensor we first wanted to make a detection system based on a fusion protein of a GHB binding protein and an enzyme. We wanted to base this on a paper from Marc Ostermeier [8] . We talked to him and found out that in our project’s timespan it’s not feasible to create this kind of fusion protein. As we learned that GHB could be endogenously present in drinks we decided to create a system with a good cutoff to distinguish between endogenous and added GHB. We started looking into bio-electrical sensors as they can provide an easy cutoff. We talked to Frans Widdershoven who developed capacitive sensors about a possible capacitance GHB sensor. He explained immobilizing biological components on electrodes could cause a capacitance difference. We decided on using a bioelectric capacitance GHB sensor.

Placement of sensor

We initally based our project on a Fiorenzo Omenetto research [1]. Omenetto conducted research on a biosensor that is attached to a tooth. We talked to him and with his recommendations, we started working on a tooth biosensor for GHB. We talked to our peers about the project and we noticed immediate pushback on the placement of the sensor on a tooth. In order to get feedback from the potential client, we set up a focus group. Together we came to three placement options:

  1. A stick that could be inserted into the beverage as needed.
  2. A biosensor could be placed on a tooth.
  3. A biosensor built into a reusable plastic glass.

initial ideas with bluetooth signal
Figure 3. Design options proposed at the focus group and during our survey.

People preferred different options and the group size was too small to draw any quantitative conclusions. We presented the design options to a larger group of people through a survey. Almost 48% preferred the glass and therefore, we decided to create a biosensor that can be installed in a glass. The main reasons were:

  1. The stick didn’t provide passive protection.
  2. When using the tooth sensor you already ingest GHB before the sensor gives the signal.
  3. The tooth sensor is very invasive

Output signal

We also performed an output signal typology study in combination with the placement investigation. Initially, we considered using a Bluetooth signal, where the sensor would be connected to an app and, in the event of a positive output, would send a direct message to you (via mobile) and an emergency contact. We spoke with owners of nightlife establishments and conducted a survey under nightclubs (N=13). They agreed that the adoption of Bluetooth might be challenging and that it would require extensive logistics. They recommended the usage of a light system, where the glass would turn on when in contact with GHB. The police suggested that the light would be the ideal implementation, and they verified that they would initiate an investigation if the light were to turn on when people were on a night out. We also contacted ‘Eerste Hulp Bij Drank en Drugsongevallen’ (EHBDD), which is the First Aid Expertise Center for Drinking and Drug Accidents. They also advised us to use a light as output, because of simplicity. As for the color of the light, the EHBDD told us orange would be the preferred color as orange is the color for GHB tests.

Legal relevance

Then we looked at what was necessary legally to make our product enforceable in spiking cases. In our survey, we first asked potential users if they thought that legal relevance was important. Almost all of them said that they would want our test to be enforceable in court. After that, we began interacting with the appropriate institution to learn more about the characteristics that would be required for our test as well as the reporting process. We specifically questioned the police, the NFI, and the Openbaar Ministerie (OM) (Dutch public prosecution service). The conclusion was that a very accurate GHB detection approach would be required if one wants to submit a report that will hold up in court. We offer a test that is quick and accurate but most likely will not have the accuracy required. However, the police acknowledged that they would be willing to move forward with the more exhaustive test in the event of a positive result. They advised us to focus on a purely qualitative test as a quantitative result is not required in a quick test. Aaldrik Krol from the Dutch national police mentioned the police would be willing to come if an SPYKE test goes off and send a sample to the NFI for confirmation.

Other uses

We initially started our project trying to create a GHB biosensor solely meant to protect people from drink spiking. As we conducted our interactions with the stakeholders we found more and more purposes for a quick GHB sensor (Figure 4). A quick GHB test could be useful for hospitals and the police to detect GHB in the body (see proposed implementation ). As for the sample, there are three types of bodily fluid from which GHB can be detected: saliva, urine and blood [5]. Of these, saliva is not a good fit to detect GHB as there is little research done, the concentrations are low and the detection window is smaller [10].

Infographic displaying possible SPYKE's other applications.

Figure 4. Infographic displaying all possible applications of SPYKE.


We talked to three medical specialists Amber Schaafsma, Corine Bethlehem and Femke Gresnigt. They told us a quick GHB sensor could be very useful for hospitals at the moment. But for this, it should be a simple, qualitative quick test to screen for GHB before performing the laborious specific test. Femke Gresnigt told us blood would be the ideal sample for hospitals as urine can be hard to extract from drugged people.


We talked to a police officer, the OM, and the NFI. At the moment, subjective cyclo-motoric tests are done to determine GHB intoxication as the on-site GHB tests are not trusted. They told us a quick GHB sensor could be useful for them in a variety of instances because at the moment no reliable one is available:

  • For spiking, as a quick test could improve the data available.
  • For traffic violations, a quick GHB is needed to determine driving under influence.
  • For violent incidences as the use of GHB changes the case enormously.
  • For forensic investigations, to immediately screen for an unnatural cause of death.

Erik Izaks explained it would be almost impossible to create an on-site test that could be used in court to confirm the presence of GHB in the body as only the very sensitive and specific mass spectrometry with blood can be used for that at the moment. Together with Eric, Mette and Cornelis we came to the best way of implementing our sensor for the police. This would be using the test as a quick test for GHB and after a positive result, the NFI could confirm the test for legal relevance. Blood would be the best sample as the police uses saliva or blood for drug tests and the forensic institute collects blood and urine. We heard from Nienke le Fever that before a drug test can be used, the test has to be validated following European guidelines [12] . The implications of this are discussed in the challenges of the proposed implementation .


At the core of our project there is safety. Incentivized both by the iGEM competition and TU Delft, we dived into all the different aspects concerning the safety and the security of SPYKE, following a Safe-by-Design approach [12]. To learn more about our Safe-by-Design approach, visit our safety page . By doing desk research and interacting with stakeholders, we identified potential risks of SPYKE. We came to mitigation strategies to minimize the chance and impact of these risks. The mitigation strategies consisted of changes in the design and implementation of SPYKE together with proposed research to increase the safety. We divided the risks and mitigation strategies over four sections. An overview of the risks and mitigation strategies can be seen in Figure 5.

potential risks and mitigation strategies
Figure 5. The potential risks and mitigation strategies resulting from the safe-by-design approach.

Food Safety

All the components of SPYKE that come into contact with the beverage should be food-safe, meaning that no microorganisms, chemicals, or materials can be present in quantities that are harmful to human health [13]. With the input of five food safety institutions we minimized the food safety risks.

  • We chose and adapted all the materials and compounds of SPYKE which could come into contact with the beverage to fall under the food safety regulations.
  • The health effects of consuming a large amount of BlcR protein has been investigated and it has a chance of ending up in the beverage. We did allergenicity and toxicology bioinformatics screenings for the protein and no hits were identified. The volume of BlcR present in SPYKE was minimized. As an extra safety layer, colored beads were added to the BlcR solution to warn the user of a large BlcR concentration in the beverage in case the filter retaining BlcR malfunctions.
Waste risk

The production and use of SPYKE can result in waste which can cause biocontamination and environmental damage.

  • To minimize the risk of biocontamination of the ampicillin resistance plasmid to the environment, Cecile van der Vlught told us to purify the BlcR protein in the factory before transporting it. She also told us that ampicillin is often used in research, and because it is not a last resort antibiotic, the consequences of contamination are minimal.
  • The one-night use components of SPYKE can result in waste and as a result, environmental damage. Together with Nemo Andrea, we created a three-layer system for the SPYKE glass which can be used to recycle individual parts easily. We also implemented a recycling system often used at large festivals to collect the glasses efficiently.
Usage risks

The (incorrect) usage of SPYKE could result in negative consequences for the user of SPYKE. The input from stakeholders changed the design and proposed implementation to minimize these risks.

  • To minimize the risks of false positives and negatives we used an electrical system with a defined cut-off value together with a two capacitor system to minimize the environmental influences.
  • Missing the warning signal from SPYKE could result in a preventable case of spiking. As advised by the users and clubs, the placement of the sensor in the glass combined with a light warning signal minimizes this risk.
  • To make sure SPYKE is handled well by the nightlife and users, Lars van Driel suggested printing a QR code on the glass with a link to the user manual.
  • To be sure SPYKE is recycled properly, we opted for recycling in the factory and not on site. Based on the input of Aaldrik Krol and a victim, we wanted to provide an option for individuals who want to have control over the situation and not have to rely on bartenders. Therefore we also provide the option to buy SPYKE independently of the nightlife establishment.
Societal risks

The existence and application of our test should not impose any harm on society. We talked to the police and the forensic institute to minimize these risks.

  • A GHB sensor on the market could shift the preferred drug for spiking to other drugs as explained by Lenneart Borra. We propose doing research on integrating already existing electrical biosensors for ketamine [14] and benzodiazapenes [15] , other drugs that can be used for spiking [16], into SPYKE.
  • As already explained in the problem section, needle spiking is another proposed way of spiking. The existence of SPYKE could steer the preferred method of spiking to needle spiking. Our other application of SPYKE as a drug test to detect GHB in the body could provide data on the disputed occurrence of needle spiking.
  • Based on the advice from clubs, not all the glasses will contain SPYKE. The police warned us this could result in the targetting of people without SPYKE. On the other hand, the victim would like to be able to recognize a SPYKE glass. As a compromise, the QR code would be attached to the bottom of the SPYKE glass so users can easily recognize the glass while bystanders cannot.

Product design

We talked to various experts to design a prototype and propose a final design of SPYKE. Jeroen Bastemeijer helped us design the circuitry of our prototype. He recommended using an Arduino system as it is easy to use and an open source system. By using Arduino, the system can be easily produced and used around the world. Initially, we planned on using one capacitor in the glass. Jeroen explained environmental influences like temperature and acidity could have a large effect on capacitance. He recommended using two identical electrodes, with the only difference being the DNA sequence. Only one of the electrodes has the BlcR binding DNA sequence and is thus responsive to GHB. By measuring the difference between these capacitors environmental influences can be filtered out. Together with Nemo Andrea, we designed the 3D printed prototype, with a screwable system for the glass. This way we created a more environmentally friendly design as the screwable system allows for easy replacements of only the relevant parts.

We did user testing with our prototype where we consulted a bartender and a possible user of SPYKE. We learned that our prototype could be improved by decreasing the size of the glass and making it see-through. The design of the 3D printed prototype and possible improvements are shown in greater detail in the hardware section . As a final check for our product, we spoke to two victims of GHB spiking as victims were the original inspiration of our project. They were pleased with the product and believe it will be beneficial. During the discussion, they put forth a final approach that involves including a device that can be purchased separately so that you may examine the drink for yourself. This was included in our final vision for SPYKE.


We looked at the full overview of our project and made sure that all pertinent values were put into it in order to strengthen our implementation vision of SPYKE into the hospitality business market. As previously stated, we intended our test to be a population-wide self-test. We began with a sensor on a tooth, which was then transformed into a biosensor in glass with the help of a focus group, surveys, and input from a number of other experts. Further, it turned out that the test may be expanded to medical facilities, as mentioned by Amber Schaafsma, Corine Bethlehem, and Femke Gresnigt. We also recognized the potential of our product in the law enforcement sector as a result of the interviews with a police officer, the OM, and the NFI. Therefore, we envision that single-users, healthcare professionals, and police officers in the target communities will conduct SPYKE. For a more thorough explanation, visit our proposed implementation page .

The cost of our device should be considerably lower than that of existing detection techniques to ensure accessibility for our target market. We created a business model and performed a market analysis to examine this. This implied that the cost of our test should be less than 5 euros. Visit our page on entrepreneurship for additional details.


  1. Tseng, P., Napier, B., Garbarini, L., Kaplan, D. L., & Omenetto, F. G. (2018). Functional, RF‐trilayer sensors for tooth‐mounted, wireless monitoring of the oral cavity and food consumption. Advanced Materials, 30(18), 1703257.
  2. Guntas, G., Mansell, T., Kim, J. and Ostermeier, M., 2005. Directed evolution of protein switches and their application to the creation of ligand-binding proteins. Proceedings of the National Academy of Sciences, 102(32), pp.11224-11229.
  3. Smits, T., Gresnigt, F., van Groen, B., Franssen, E. and Attema-de Jonge, M., 2020. Prospective Investigation of the Performance of 2 Gamma-Hydroxybutyric Acid Tests: DrugCheck GHB Single Test and Viva-E GHB Immunoassay. Therapeutic Drug Monitoring, 42(1), pp.139-145.
  4. Jansen, N. and Gortworst, J., 2022. Overal berichten over drogeringen in uitgaansleven: hoe zit dat?. [online] Retrieved 20 september 2022. Available at: .
  5. van Beek, R. and van Goor, M., 2022. Drugs in drankjes: waarom onderzoek naar drogeren zo lastig is. [online] Retrieved 20 september 2022. Available at:
  6. Németh Z, Kun B, Demetrovics Z. Review: The involvement of gamma-hydroxybutyrate in reported sexual assaults: a systematic review. Journal of Psychopharmacology. 2010;24(9):1281-1287.
  7. (2022). Drink Spiking – Know the facts and protect your customers. [online] Retrieved 22 september 2022. Available at: .
  8. Oxford Treatment Center. (n.d.). How Long Does GHB Stay in Your System? [online] Retrieved 2 July 2022. Available at:
  9. Bullmann, M., 2021. GHB Spiking in Amsterdam: The New Normal?. [online] Retrieved 20 september 2022. Available at:
  10. (n.d.) A COMMUNITY-LED SPIKING DATABASE TO KEEP YOU AND YOUR MATES SAFE. [online] Retrieved 10 October 2022. Available at: .
  11. Fasel, Z., 2022. ‘Needle spiking’: dit weten we van drogeren met injectienaalden. [online] Retrieved 24 August 2022. Available at:
  12. Abanades, S., Farré, M., Segura, M., Pichini, S., Pastor, A., Pacifici, R., Pellegrini, M. and Torre, R., 2007. Disposition of Gamma-Hydroxybutyric Acid in Conventional and Nonconventional Biologic Fluids After Single Drug Administration: Issues in Methodology and Drug Monitoring. Therapeutic Drug Monitoring, 29(1), pp.64-70.
  13. Kintz, P., Goullé, J., Cirimele, V. and Ludes, B., 2001. Window of Detection of γ-Hydroxybutyrate in Blood and Saliva. Clinical Chemistry, 47(11), pp.2033-2034.
  14. 2022. Een drugstest bij politiecontrole: hoe werkt dat?. [online] Retrieved 29 September 2022. Available at:
  15. 2022. - Regeling - Regeling alcohol, drugs en geneesmiddelen in het verkeer - BWBR0039687. [online] Retrieved 29 September 2022. Available at: .
  16. 2017. Voedselveiligheid. [online] Retrieved 6 September 2022. Available at:,schadelijk%20zijn%20voor%20de%20mens
  17. Fu, K., Zhang, R., He, J., Bai, H., & Zhang, G. (2019, October). Sensitive detection of ketamine with an electrochemical sensor based on UV-induced polymerized molecularly imprinted membranes at graphene and MOFs modified electrode. Biosensors and Bioelectronics, 143, 111636.
  18. Ashrafi, H., Hassanpour, S., Saadati, A., Hasanzadeh, M., Ansarin, K., Ozkan, S. A., Shadjou, N., & Jouyban, A. (2019, March). Sensitive detection and determination of benzodiazepines using silver nanoparticles-N-GQDs ink modified electrode: A new platform for modern pharmaceutical analysis. Microchemical Journal, 145, 1050–1057.
  19. Banyan Treatment Center. 2022. The Most Common Date Rape Drug | Banyan Philadelphia. [online] Retrieved 6 July 2022. Available at: .