DEVELOPMENT OF A BIOSENSOR FOR OBJECTIVELY QUANTIFYING NUISANCE ODORS NEAR LANDFILLS

Nuisance odors from landfills have more impact than just being an annoyance to nearby residents. With an ever-increasing population, a larger number of communities are located in closer proximity to landfills than ever before. This has brought along with it, more regular conflicts with landfill authorities surrounding the issue of odors, resulting in complaints, lawsuits, fines, and even re-siting operations. The absence of an objective method of quantifying nuisance odors makes the task of creating regulations and setting standards even more complicated. The current research focuses on a method to objectively quantify landfill odors. The human odorant binding protein 2A (hOBPIIa) can be produced using published recombinant gene technology and can be used as a biosensor to quantify odorants through spectrofluorometric measurements. The current work is a continuation of the previous work by Rahman (2020). In this work, the spent biosensor after it reacts with an odorant is shown to be regenerated by applying additional fluorophore following La Chateliers’ principle, so that the same batch of protein can be used to run multiple experiments with odorants. An important part of the work miniaturized the earlier version of the experimental setup and incorporates a much more efficient flow-through system. This setup is capable of collecting real-time readings, increasing the overall accuracy and shortening the duration of each set of the experiment. The current work also explores the response of the biosensor with an expanded group of pure odorants, including hydrogen sulfide, ammonia, toluene, formaldehyde, tert-butyl mercaptan, and methyl mercaptan as well as their mixtures, thus expanding the list of odorants tested under this principle. The results show that the protein shows a concentration-dependent response differing on the hydrophobicity of the target compound.