iGEM 2023 — Team makerere-uganda

{% extends "layout.html" %}
{% block title %}Notebook -{% endblock %}
{% block page\_content %}

![Header](https://static.igem.wiki/teams/5019/wiki/notebook/0-header.jpg)

![](https://static.igem.wiki/teams/5019/wiki/notebook/1-march.jpg)

### March

>

#### Week 1: Ideation and brainstorming

The team came together at the SynBio Africa offices to brainstorm and generate project ideas aimed at addressing the challenge of PAH detection in water. Collaboratively, we explored various concepts and proposals, with each team member actively contributing their thoughts. It was during this productive session that a standout idea emerged as the development of a biosensor specifically designed for the detection of polyaromatic hydrocarbons in water. We want to express our sincere gratitude to the SynBio Africa team, with special thanks to Mr. Otim and Perez, for their invaluable support and guidance during this pivotal brainstorming session.

#### Week 2, Week 3 & Week 4 | Proposal development |

Recognizing the importance of a strong foundation for our project, we decided to start by thoroughly reviewing the existing literature on PAHs. During this phase, each team member was assigned a specific section of the literature related to PAHs. Each member diligently studied their assigned section, extracting valuable information, data, and relevant research findings.

* Chapter 1: Introduction

  Authors: Ian & Michael
* Chapter 2: Literature Review

  Authors: Gloria & Shakirah
* Chapter 3: Methodology

  Authors: Peace, Arnold & Ian

The division of responsibilities ensured that each section receives dedicated attention and expertise from the team members responsible.

![](https://static.igem.wiki/teams/5019/wiki/notebook/1-april.jpg)

### April

#### Week 1: Concept development and project planning

We diligently worked on refining the concept for the biosensor project.

1. Defining Project Objectives: We clearly outlined the primary objectives of the project, setting specific goals for what we aimed to achieve.

![](https://static.igem.wiki/teams/5019/wiki/notebook/2-april.jpg)

2. Creating an Initial Project Plan: With a clear understanding of our objectives and challenges, we began the process of crafting an initial project plan. Originally, our strategy was to have a biosensor for both water and soil detection, however due to limited funds for analysis of the samples, we chose to stick to water samples.

This plan outlined the various stages and steps required to bring our biosensor project to fruition. During this phase, we had the privilege of meeting with Dr. Julius, whose expertise and guidance were instrumental in helping us develop a rational and well-structured study design. Dr. Julius' insights played a crucial role in shaping the direction of our project and ensuring its scientific rigor and feasibility.

#### Week 3 | Conducting initial surveys for data collection

The team developed surveys to collect data related to PAH contamination in various water sources. Survey questions were designed to gather information on PAH prevalence, sources of contamination, and. This was headed by the Head of Research for our team, Shakirah Namuli.

Each team member contributed 5,000 Uganda shillings for transport. We used Arnold’s vehicle to transport us to and fro.

![Left Arrow](https://static.igem.wiki/teams/5019/wiki/sampling/left-arrow.png)

![Right Arrow](https://static.igem.wiki/teams/5019/wiki/sampling/right-arrow.png)

![Katanga](https://static.igem.wiki/teams/5019/wiki/notebook/kikoni99.jpg)

Kikoni

![Bwaise 2](https://static.igem.wiki/teams/5019/wiki/notebook/nakulabye54.jpg)

Nakulabye

![Bwaise 2](https://static.igem.wiki/teams/5019/wiki/sampling/rubbish-in-kikoni.jpeg)

Kikoni

![Bwaise](https://static.igem.wiki/teams/5019/wiki/sampling/bwaise2.jpg)

Bwaise

![Nakulabye](https://static.igem.wiki/teams/5019/wiki/sampling/nakulabye.jpg)

Nakulabye

![Nakulabye](https://static.igem.wiki/teams/5019/wiki/sampling/img-20230513-wa0078.jpg)

Kikoni

![Gayaza](https://static.igem.wiki/teams/5019/wiki/sampling/gayaza.jpg)

Gayaza

![Jinja Kaloli](https://static.igem.wiki/teams/5019/wiki/sampling/jinja-kalori.jpg)

Jinja Kalori (Maganjo Stone Quarry)

![Kalerwe](https://static.igem.wiki/teams/5019/wiki/sampling/kalerwe1.jpg)

Kalerwe

![Katanga](https://static.igem.wiki/teams/5019/wiki/notebook/kikoni3.jpg)

Kikoni

![Gayaza](https://static.igem.wiki/teams/5019/wiki/sampling/header-image.jpg)

Jinja Kalori (Maganjo Stone Quarry)

![Katanga](https://static.igem.wiki/teams/5019/wiki/notebook/jinja-kalori877.jpg)

Jinja Kalori (Maganjo stone quarry)

![Kikoni](https://static.igem.wiki/teams/5019/wiki/sampling/whatsapp-image-2023-05-13-at-9-00-11-pm.jpeg)

Kikoni (Bulesa)

![](https://static.igem.wiki/teams/5019/wiki/notebook/4-april.png)

#### |Week 4 | Fundraising |

Our fundraising efforts were a vital part of our journey to participate in the iGEM competition and execute our research project effectively.

**1. Assessment of Funding Needs:** Before embarking on fundraising, we conducted a thorough assessment of our financial requirements. This included estimating the costs associated with project materials, laboratory equipment, travel expenses, and registration fees for the iGEM competition.

![](https://static.igem.wiki/teams/5019/wiki/notebook/5-april.jpeg)

**2. GoFundMe Campaign:** One of our primary fundraising initiatives was the creation of a GoFundMe campaign. This online crowdfunding platform allowed us to reach a global audience and collect donations from individuals and organizations who believed in our project.

**3. Awareness and Outreach:** To promote our GoFundMe campaign, we leveraged various channels of communication. This included using social media platforms to spread the word about our fundraising efforts.

**4. Engaging with Stakeholder:** We actively engaged with stakeholders, including government agencies, and academic institutions, to seek financial support.

![](https://static.igem.wiki/teams/5019/wiki/notebook/may.png)

### May

#### | Week 1, 2, 3 & 4; Fundraising|

Through out May, we dedicated most of our time to fundraising. It was such a critical time and at some point we fell into despair. We were in need of funds to pay for the Jamboree registration. We also needed money to carry out the analysis of samples before we could sample from the surveyed.

![](https://static.igem.wiki/teams/5019/wiki/notebook/1-june.png)

### June

#### | Week 1, 2 & 4 | Fundraising

We continued to fundraise through out most of June. As contributions began to come in, we finally started seeing light at the end of the tunnel.

That was the time when Prof. Gerald Kayingo from University of Maryland stepped in to pay for the start up fees for our GC-MS analysis. Our PI Dr. Julius Mulindwa also came into support by paying for part of the analysis as well.

![](https://static.igem.wiki/teams/5019/wiki/notebook/2-june.png)

![](https://static.igem.wiki/teams/5019/wiki/notebook/3-june.png)

![](https://static.igem.wiki/teams/5019/wiki/notebook/sampling.jpg)

#### | Week 3. Sampling |

#### Collecting water samples for PAH analysis

**Site Selection:** Since we lacked enough funds for the analysis we selected only five sites from where we could sample out of the ten sites we surveyed.

**Sample Labeling and Documentation:** Each sample was carefully labeled with essential information, including the date and location. Detailed documentation was crucial for subsequent analysis and tracking.

**Transport and Storage:** After collection, the samples were transported to the Government Analytical laboratory. Maintaining proper storage conditions prevented the degradation of PAH compounds.

![](https://static.igem.wiki/teams/5019/wiki/notebook/1-july-header.jpg)

July

#### | Week 1 | Fundraising |

Thanks to everyone who supported us and believed in us, our fundraising efforts in order for us to register for the Jamboree started to pay off. The Go fund me account that had been empty for several months really started to pick momentum. The SynBio Africa community worked tirelessly especially Mr. Emmanuel Kato to see to it that we secure funds for the Jamboree.

![](https://static.igem.wiki/teams/5019/wiki/notebook/2-july.jpg)

#### | Week 2 | Attending the SynBio Africa Conference and iGEM Strat up Summer School

![](https://static.igem.wiki/teams/5019/wiki/notebook/4-julyt.jpg)

Attending the SynBio Africa Conference was a transformative experience that opened doors to a world of knowledge, collaboration, and inspiration. During this conference, we had the privilege of interacting with a diverse array of stakeholders, scientists, and entrepreneurs who left an indelible mark on our project.

![](https://static.igem.wiki/teams/5019/wiki/notebook/proff-voigt.jpg)

We met Prof. Voigt from MIT a pioneering figure in the field of synthetic biology, offering us valuable insights and guidance. John Cumbers, the driving force behind SynBio Beta, Michael Kopke, Andrew Hessel, and their entrepreneurial journeys illuminated the intersection of science and business, demonstrating the potential for our research to drive real-world impact.

![](https://static.igem.wiki/teams/5019/wiki/notebook/kiggundu.jpg)

Dr. Andrew Kiggundu's wealth of knowledge in biotechnology, regulatory affairs, and project management was a valuable resource that helped us navigate the complexities of our project. Dr. Benson Kinyagia's role as a Senior Science Secretary at The National Commission for Science Technology and Innovation in Nairobi, Kenya, offered us a glimpse into the regulatory landscape of biotechnology in Africa.

One of the most significant turning points in our fundraising journey was iduring this conference when LanzaTech, a company that believed in our project, generously sponsored our entire registration fee for the iGEM competition. Their support played a crucial role in making our participation possible.

![](https://static.igem.wiki/teams/5019/wiki/notebook/poster-1.jpg)

#### Poster Presentation

One of the highlights of our conference participation was the opportunity to present a poster on our project. This presentation allowed us to showcase our research, receive valuable feedback, and foster connections within the scientific community. The SynBio Africa Conference not only enriched our scientific knowledge but also provided a platform for us to engage with experts, share our ideas, and lay the groundwork for collaborations that would shape the trajectory of our iGEM journey.

The conference was a pivotal moment in our project, where we gathered inspiration, insights, and connections that would propel us forward on our path to innovation and impact. It reinforced the importance of networking and collaboration in the world of science and underscored the limitless potential of our iGEM project in the context of global synthetic biology.

![](https://static.igem.wiki/teams/5019/wiki/notebook/synnnnnnnnnnnnnn-4.jpg)

![Left Arrow](https://static.igem.wiki/teams/5019/wiki/sampling/left-arrow.png)

![Right Arrow](https://static.igem.wiki/teams/5019/wiki/sampling/right-arrow.png)

![Kalerwe 2](https://static.igem.wiki/teams/5019/wiki/notebook/3day-40.jpg)
![Kawempe Nabukalu](https://static.igem.wiki/teams/5019/wiki/notebook/synnn-11.jpg)
![Katanga](https://static.igem.wiki/teams/5019/wiki/notebook/img-20230716-wa0022.jpg)
![Katanga](https://static.igem.wiki/teams/5019/wiki/notebook/33333-3.jpg)
![Kawempe Nabukalu](https://static.igem.wiki/teams/5019/wiki/notebook/whatsapp-image-2023-09-07-at-3-42-52-am.jpeg)
![Kawempe Nabukalu](https://static.igem.wiki/teams/5019/wiki/notebook/222dayy-12.jpg)
![Kikoni](https://static.igem.wiki/teams/5019/wiki/notebook/222dayyy-16.jpg)
![Kikoni](https://static.igem.wiki/teams/5019/wiki/notebook/2-july.jpg)
![Kikoni](https://static.igem.wiki/teams/5019/wiki/notebook/proff-voigt.jpg)
![Kikoni](https://static.igem.wiki/teams/5019/wiki/notebook/poster-1.jpg)
![Kikoni](https://static.igem.wiki/teams/5019/wiki/sampling/synnnnnnn-4.jpg)
![Katanga](https://static.igem.wiki/teams/5019/wiki/notebook/synnnn-19.jpg)

#### Attending the iGEM Start up Summer School

During the summer school, we delved into various aspects of start-up knowledge, including business development, intellectual property rights, and the practicalities of taking a synthetic biology project from the lab to the market. These sessions equipped us with essential skills for turning our research into a viable solution that could make a real impact in addressing the issue of PAH contamination.

![](https://static.igem.wiki/teams/5019/wiki/notebook/f1lpgbmwwai1d2p.jpeg)

#### | Week 3: Go Green Cycle |

#### Our participation in the Go Green cycle reflects our commitment to developing a biosensor that not only addresses the urgent issue of PAH contamination but also so with a strong focus on environmental responsibility. We strive to embody the principles of sustainability, ethics, and ecological awareness in every aspect of our project, aiming for a positive and lasting impact on the environment and society as a whole.

![](https://static.igem.wiki/teams/5019/wiki/notebook/go-green-cycle-2.jpg)

![](https://static.igem.wiki/teams/5019/wiki/notebook/go-green-cycle.jpg)

![](https://static.igem.wiki/teams/5019/wiki/notebook/img-20230731-wa0046.jpg)

![](https://static.igem.wiki/teams/5019/wiki/notebook/img-20230730-wa0009.jpg)

![](https://static.igem.wiki/teams/5019/wiki/notebook/20230715-130711.jpg)

#### | Week 4 | Starting data analysis, including sorting of relevant PAHs |

**Statistical Analysis:** Data analysis also involved statistical methods to identify patterns, trends, and correlations within the dataset. This statistical analysis helped us draw meaningful conclusions about the distribution and behavior of PAHs in the sampled sites.

**Identification of Relevant PAHs:** Not all PAHs are of equal concern in terms of environmental impact. Some are more toxic or persistent than others. Mr. Erikan Baluku and Dr. Julius provided their expertise in identifying the PAHs that were most relevant to our project's goals. These were the compounds that posed the highest risks to the environment and public health.

**Sorting and Prioritization:** Once the relevant PAHs were identified, we sorted and prioritized them based on factors such as toxicity, concentration levels, and their potential to accumulate in the food chain. This step was crucial in determining which PAHs required closer examination and mitigation strategies.

**Statistical Analysis:** Data analysis also involved statistical methods to identify patterns, trends, and correlations within the dataset. This statistical analysis helped us draw meaningful conclusions about the distribution and behavior of PAHs in the sampled water bodies.**Project Direction:** The insights gained from data analysis guided our project's direction. It informed decisions about which PAHs to target for detection and mitigation strategies, ultimately shaping the development of our biosensor for PAH detection.

#### August

#### | Week 1, 2, 3 & 4 |

#### This was a marathon month of searching for PAH degrading microbes and coming up with the genetic construct.

![](https://static.igem.wiki/teams/5019/wiki/notebook/phenn.png)

![](https://static.igem.wiki/teams/5019/wiki/notebook/operon.jpg)

Our team collectively engaged in an extensive literature review focused on phenanthrene and pyrene-degrading organisms. This literature review was a collaborative effort, with each team member actively participating. It involved delving into existing scientific research and studies related to microorganisms capable of degrading phenanthrene and pyrene, which are key PAHs of concern in our project.

The objective of this literature review was to gain comprehensive insights into the characteristics, mechanisms, and potential applications of these degrading organisms. By pooling our research findings and knowledge, we aimed to identify promising candidates and essential genetic information that could be leveraged in the development of our biosensor project.

![](https://static.igem.wiki/teams/5019/wiki/notebook/screenshot-174.png)

Ms. Tyra from IDT and Prince Samoh from Open Bioeconomy Lab played instrumental roles in equipping our team with essential skills for genetic construct design. They provided guidance on utilizing various software tools, notably SnapGene and Benchling, which are fundamental in the field of synthetic biology. Through their mentorship, we gained a comprehensive understanding of the underlying principles of effective genetic design. Their expertise and willingness to share knowledge greatly enhanced our capabilities and confidence in handling genetic constructs. We extend our sincere gratitude to Ms. Tyra and Prince Samoh for their dedicated support.

![](https://static.igem.wiki/teams/5019/wiki/notebook/screenshot-113.png)

#### September

#### | Week 1: Ordering for genetic constructs from IDT and Wiki Development |

During the wiki development process, Bridget played a pivotal role by diligently uploading the initial content, setting the foundation for our project's online presence.

Following Bridget's contributions, Thomas and Stephen stepped in to incorporate visually appealing designs and enhance the overall user experience. Throughout this wiki development journey, Shakirah took on the crucial role of overseeing the entire process. Her leadership ensured that the content remained cohesive, well-structured, and aligned with our project's goals. Shakirah's dedication to quality control has been instrumental in creating a comprehensive and user-friendly platform.

![](https://static.igem.wiki/teams/5019/wiki/notebook/sdgs.jpg)

#### | Week 2 | PRESENTATION ON SUSTAINABLE DEVELOPMENT GOALS: Collaboration with Tsinghua-TFL iGEM team

![](https://static.igem.wiki/teams/5019/wiki/notebook/sdgf.png)

Together with the Tsinghua-TFL team, we delved into the importance of SDGs in the context of our respective projects. We discussed how synthetic biology and biotechnology can contribute to addressing some of the pressing challenges outlined in the SDGs, particularly those related to environmental conservation, public health, and sustainable agriculture.

Our joint presentation highlighted the power of international collaboration and knowledge sharing within the iGEM community. We exchanged insights and ideas, learning from each other's experiences and perspectives.

![](https://static.igem.wiki/teams/5019/wiki/notebook/microplastics.jpg)

#### | Week 3: Attending the Microplastic Webinar |

In the webinar, experts and researchers shared their insights and findings on the presence, impact, and detection of microplastics in various ecosystems. We learned about the wide-ranging effects of microplastics on aquatic life, ecosystems, and human health, emphasizing the urgency of addressing this issue.

Attending the Microplastics webinar aligned with our project's focus on environmental concerns, as microplastics and PAHs often coexist in contaminated water sources. This exposure allowed us to explore potential intersections between our research on PAH detection and the broader environmental context of microplastic pollution.

# PAHs in the Environment Webinar

![](https://static.igem.wiki/teams/5019/wiki/notebook/webinar.jpg)

#### | Week 4 | Hosting PAHs in the Environment Webinar |

We took the initiative to host an online seminar titled "PAHs in the Environment." It aimed to bring together stakeholders, scientists, and experts to delve into the pressing issue of Polycyclic Aromatic Hydrocarbons (PAHs) in the environment.
During this event, we featured a diverse panel of experts, including an academic, a food scientist, a GC-MS specialist, a public health specialist, and an aquaculture scientist, each bringing their unique perspectives on the impact of PAHs on the environment and public health.

The seminar covered various aspects related to PAHs, from their sources and distribution in the environment to their potential health implications and innovative detection methods, such as biosensors. We aimed to create a platform for in-depth discussions, knowledge sharing, and awareness-raising about the challenges and opportunities surrounding PAHs as well as the need for field adaptable systems for PAHs detection.

![](https://static.igem.wiki/teams/5019/wiki/image-note-book.jpg)

{% endblock %}


{% extends "layout.html" %}
{% block title %}Experiments -{% endblock %}
{% block page\_content %}

![](https://static.igem.wiki/teams/5019/wiki/photo-from-michael-okea.jpg)

# GC-MS PROTOCAL

PAHs are fortunately one of those compounds that are highly familiar to routine environmental or contract testing laboratories. Gas chromatography-mass spectrometry (GC-MS) is well suited for their analysis. Single quadrupole GC-MS offered the opportunity for the environmental laboratory to increase selectivity for these analytes over that of classical detectors, such as UV and florescence detectors in HPLC and ECD and FID detectors in GC- MS. This allowed for limited optimization of sample preparation procedures to increase time to result and ultimately reduce laboratory costs. Triple quadrupole meanwhile GC-MS/MS provides a significant increase in selectivity when compared to single quadrupole GC-MS. This selectivity profoundly affects the ability to cut through chemical background (interference), which enhances the capability and productivity of environmental testing laboratories, that are now increasingly utilizing the techniqe, especially those looking for a competitive edge. Unfortunately, for laboratories newer to GC-MS/MS, the adoption of the technique presents a challenge in realizing the productivity advantages offered without significantly impacting continued laboratory operations.

## SAMPLING

The samples were collected from 5 sites within the Kampala metropolitan area. The water was scooped by a person wearing gloves and filled into an opaque 1L bottle then sealed tightly and transported to the Directorate of Government Analytical Laboratory for analysis.

### EXPERIMENTAL CONDITIONS/PROCEDURE.

* To 1 L of sample, hexane was added and the mixture was shaken.
* The water and organic phases were separated, and the organic phase was removed and dried with anhydrous Na2SO4.
* An aliquot of the organic extract was evaporated to a volume of 3-4 mL and then evaporated under a gentle nitrogen stream to a final volume that was analysed using Gas chromatography.

{% endblock %}

{% extends "layout.html" %}
{% block title %}Results -{% endblock %}
{% block page\_content %}

### RESULTS FROM GC MS ANALYSIS OF SAMPLES

![](https://static.igem.wiki/teams/5019/wiki/assets/gc-ms-results.jpg)

![](https://static.igem.wiki/teams/5019/wiki/assets/lod-1.jpg)

Limit of detection for the various PAHs

K-means clustering details:

| Cluster | Members |
| --- | --- |
| Cluster 1 | SP31, SP32, SP33, SP41, SP42, SP43 |
| Cluster 2 | SP1, SP2, SP3 |
| Cluster 3 | SP21, SP22, SP23, SP51, SP52, SP53 |

Clustering of samples based on similarity of concentration of PAHs

![](https://static.igem.wiki/teams/5019/wiki/pic-2.jpg)

Principle Component Analysis: Sample 1 and Sample 4 share similarity in low concentration of various PAHs while Sample 2 and Sample 5 share similarity in high concentration of various PAHs. Sample 3 has a more or less balanced concentration of PAHs.

![](https://static.igem.wiki/teams/5019/wiki/pic3.jpg)

Varying concentration of PAH concentration across the different samples

Based on the two samples, sample 1 and sample 2, we scored PAHs that were highly concentrated in a relatively balanced distribution in both samples. These included Benz(a)anthracene, pyrene, acenaphthylene, fluoranthene, 1- methylnaphthalene and phenanthrene.

### PAH ANALYSIS BASED ON SAMPLE SITES

#### Sample 1: Jinja Kaloli

The PAH levels in Jinja Kaloli are relatively low for most compounds, with only 2-Methylnaphthalene and 1-Methylnaphthalene showing significant concentrations. This suggests that this site might have minimal PAH pollution or contamination.

#### Sample 2: Bwaise II

The concentrations of PAHs in Bwaise II are notably high across several compounds. Almost all the PAHs listed have been detected in significant amounts, with 2-Methylnaphthalene, 1-Methylnaphthalene, and Fluorene having particularly high concentrations. Bwaise II seems to be a hotspot for PAH contamination. The presence of multiple PAHs in significant concentrations indicates potential industrial activities or other sources of pollution in the area.

#### Sample 3. Katanga

Katanga shows a mixed profile with some PAHs like Naphthalene, 2-Methylnaphthalene, and 1-Methylnaphthalene present in high concentrations, while others like acenaphthylene, Fluoranthene, and Pyrene are absent. The presence of specific PAHs and absence of others might indicate specific sources of pollution in Katanga. It's essential to investigate further to determine the exact cause of these PAH concentrations.

#### Sample 4: Kalerwe

Kalerwe has a unique profile with a very high concentration of Naphthalene. However, many other PAHs are absent. The high concentration of Naphthalene suggests a specific source of contamination in Kalerwe. It might be related to specific industrial activities or other localized sources of pollution.

#### Sample 5: Kikoni

Kikoni has high concentrations of several PAHs, notably Naphthalene, 2-Methylnaphthalene, 1-Methylnaphthalene, and Pyrene. This suggests a significant level of PAH contamination, possibly from various sources.

#### General Observation and Recommendations

The PAH analysis indicates varying levels of contamination across the different sample sites. Bwaise II and Kikoni stand out as significant hotspots for PAH contamination, while Jinja Kaloli seems to have minimal PAH pollution. It's crucial to understand the sources of these PAHs to implement effective mitigation measures.

### SCORING RELEVANT PAHS

| PAHs | Persistence in Environment | Prevalence | Application | Toxicity | Priority List | Substance of high concern | Persistance in water |
| --- | --- | --- | --- | --- | --- | --- | --- |
| Pyrene | High | Widely Distributed | Industrial & Combustion Processes | Moderate to High Toxicity | EPA Priority Chemical | Yes | Moderate |
| Acenaphthylene | Moderate | Industrial & Urban Environment | Chemical Production, Research | Limited Toxicity Information Available | Not Specified | Not Specified | Low |
| Flouranthene | Moderate | Industrial & Urban Environment | Combustion & Chemical Production | Moderate Toxicity | EPA Priority Chemical | Yes | Moderate |
| Benz[a]anthracene | High | Industrial & Urban Environment | Combustion & Industrial Processes | Moderate Toxicity | Yes | Yes | Moderate |
| 1-Methylnaphthalene | Low | Industrial & Urban Environment | Solvent Chemical Intermediate | Low Toxicity Info Available | Not Specified | Not Specified | Low |
| Phenanthrene | High | Widespread in Soil, Water, and Air | Combustion & Industrial Processes | Moderate to High | EPA Priority Chemical | Yes | High |

The concentrations of different PAH compounds vary across the water samples. This variability suggests that the sources of these compounds are diverse, and not all PAHs are equally present in the samples. Some PAH compounds are present at higher levels compared to others. This indicates that these compounds may originate from different sources, such as industrial processes, vehicular emissions, or natural occurrences.

### SPECIFIC SAMPLES

Low Concentration Samples: Sample 1 and Sample 4 have the least concentration of PAHs. These samples may come from sources with lower levels of pollution or better filtration methods.

High Concentration Samples: Sample 2 and Sample 5 have the highest concentration of PAHs. These could be from sources with higher levels of pollution or less effective filtration methods.We therefore decided to focus on these two samples to choose ideal PAH candidates for the biosensor.

### IDEAL CANDIDATES FOR THE BIOSENSOR

Pyrene: This compound scores highest in all ranking categories, making it very ideal for the biosensor model. The high limit of detection of 0.3 for Pyrene when using GC-MS suggests that it is particularly well-suited for applications where the target analytes are expected to be present in higher concentrations. While GC-MS is a powerful tool for qualitative and quantitative analysis, its higher limit of detection may not be ideal for detecting trace amounts of substances. However, this is where the biosensor model excels. It could be particularly useful for real-time, on-site monitoring of pyrene in environments where low-level detection is crucial, such as in water quality assessment or air pollution monitoring. The biosensor's capabilities can fill the gaps left by the limitations of GC-MS, offering a more comprehensive and nuanced approach to pyrene detection.

Phenanthrene: This is also a priority PAH and is fairly distributed across the five samples. Given its prevalence and importance, it is a suitable candidate for detection. Due to its prevalence, phenanthrene can serve as a marker or indicator compound for the presence of other, potentially more harmful, PAHs. Its widespread occurrence across samples suggests that it is easier to detect, making it a suitable candidate for calibration and quality control in analytical methods.

### CONCLUSION

Based on the observed variations in PAH concentrations and their distribution across different samples, the biosensor will be designed to detect two key compounds: Phenanthrene and Pyrene. These compounds are not only prevalent but also likely represent different sources, making them ideal markers for monitoring water quality.

By focusing on these two compounds, the biosensor aims to provide a reliable and effective method for detecting harmful PAH levels in water used for various purposes, thereby contributing to better environmental management and public health.

References

Archived copy" (PDF). Archived from the original (PDF) on 2012-09-11. Retrieved 2012-07-30. "Six new substances added to the Candidate List ECHA/PR/19/01". Retrieved 2019-01-17. ^Zelinkova, Zuzana; Wenzl, Thomas (2015). "The Occurrence of 16 EPA PAHs in Food – A Review". Polycyclic Aromatic Compounds. 35 (2–4): 248–284. doi:10.1080/10406638.2014.918550. PMC 4673601. PMID 26681897. https://echa.europa.eu/documents/10162/c62a1c4a-ceec-3a00-52a4-0a298f7d8bb3

Senkan, Selim and Castaldi, Marco (2003) "Combustion" in Ullmann's Encyclopedia of Industrial Chemistry, Wiley-VCH, Weinheim. https://www.cdc.gov/biomonitoring/contact\_us.html

carcinogenicity.https://regenesis.com/en/glossary/acenaphthylene/ US Agency for Toxic Substances & Disease Registry (ATSDR). (cited November 8, 2013). . Available from http://www.atsdr.cdc.gov/spl/.

Abdel-Shafy, H. I., & Mansour, M. S. M. (2016). A review on polycyclic aromatic hydrocarbons: Source, environmental impact, effect on human health and remediation. In Egyptian Journal of Petroleum (Vol. 25, Issue 1). https://doi.org/10.1016/j.ejpe.2015.03.011

Adeniji, A. O., Okoh, O. O., &Okoh, A. I. (2018). Analytical Methods for Polycyclic Aromatic Hydrocarbons and their Global Trend of Distribution in Water and Sediment: A Review. In Recent Insights in Petroleum Science and Engineering. InTech. https://doi.org/10.5772/intechopen.71163

Gajendra,K.G.,Ashutosh,K.,Amit,K.T.,&Rahul,K.(2022).Sensor Methods for the Detection of Polycyclic Aromatic Hydrocarbons (PAHs) in Industrial Wastewater.

{% endblock %}