We developed curved spiral antennas for use in underwater (freshwater) communications. Specifically, these antennas will be integrated in so-called mussel backpacks. Backpacks are compact electronics that incorporate sensors and a small radio that operate around 300 MHz. Researchers attach these backpacks in their freshwater mussel related research. The antennas must be small, lightweight, and form-fit the mussel. Additionally, since the mussel orientation is unknown, the antennas must have broad radiation patterns. Further, the electromagnetic environment changes significantly as the mussels burrow into the river bottom. Broadband antennas, such a spiral antennas, will perform better in this instance. While spiral antennas are well established, there has been little work on their performance in freshwater. Additionally, there has been some work on curved spiral antennas, but this work focused on curving in one dimension, namely curving around a cylinder. In this thesis we develop spiral antennas that curve in two dimensions in order to conform the contour of a mussel's shell. Our research has three components, namely (a) an investigation of the relevant theoretical underpinning of spiral antennas, (b) extensive computer simulations using state-of-the art computational electromagnetics (CEM) simulation software, and (c) experimental validation. The experimental validation was performed in a large tank in a laboratory setting. We also validated some designs in a pool (∼300,000 liters of water and ∼410 squared-meter dive pool) with the aid of a certified diver. To use CEM software and perform successful antenna-related experiments require careful attention to many details. The mathematical description of radiation from an antenna, antenna input impedance and so on, is inherently complex. Engineers often make simplifying assumptions such as assuming no reflections, or an isotropic propagation environment, or operation in the antenna far field, and so on. This makes experiments on antennas challenging since it often quite difficult to replicate the simplifying assumptions in an experimental setting. Still, with careful consideration of the important factors and careful experimental design it is possible to perform successful experiments. For example, antenna measurements are often performed in anechoic chambers. For our research we used a large swimming pool to mimic an underwater anechoic chamber. Our CEM simulations and experimental results are in most cases congruent. We are confident that we can design formfitting, compact (spiral) antennas that one could deploy on mussels. This will greatly enhance the mussel backpacks that are used by researchers at the University of Iowa.

Les cryptophanes constituent une famille de conteneurs moléculaires, caractérisés par leur cavité interne lipophile. La capacité des cryptophanes à encapsuler du xénon hyperpolarisé a ouvert une grande opportunité de développer des traceurs d’IRM moléculaires à base de 129-Xe. Un grand nombre de biocapteurs 129-Xe-cryptophane ont été développés pour cibler divers événements biologiques. Bien que ce concept soit accrocheur, de nombreux défis ont été rencontrés, en particulier dans l’élaboration de dérivés de cryptophane solubles dans l’eau et fonctionnalisables facilement. Cette thèse vise donc à développer une nouvelle approche simple pour synthétiser des capteurs de cryptophane solubles dans l’eau. Ces cages sont basées sur des dérivés de cryptophane [223] portant une fonction acide carboxylique centrale permettant de greffer de manière sélective une unité de détection et sur six précurseurs solubles dans l’eau sur les deux rebords du CTB. Le greffage de différents bras de détection a été réalisé en une seule étape, suivie d’une simple déprotection pour offrir les capteurs de cryptophane solubles dans l’eau. Ces capteurs ont été caractérisés par spectroscopie RMN 129-Xe pour évaluer leurs propriétés de liaison et leur réactivité. Un autre aspect de ces dérivés est leur capacité à subir un phénomène d’self-encapsulation dépendant de solvants, caractérisé par l’inclusion de la fonctionnalité centrale greffée sur le lieur propélendioxy vers la cavité interne des cryptophanes en l’absence d’invité. L’investigation de «l’auto-encapsulation» a été évaluée par spectroscopie RMN 1H et IR qui a révélé certains signaux caractéristiques correspondant à ce processus. L'effet sur les propriétés chiroptiques globales a également été étudié par spectroscopie polarimétrique, VCD et ECD. / Cryptophanes are a family of molecular containers, characterized by their lipophilic internal cavity. The ability of cryptophanes to encapsulate hyperpolarized xenon has opened a great opportunity to develop highly sensitive 129-Xe-based MRI molecular tracers. A large number of 129-Xe-cryptophane biosensors have been developed for targeting various biological events. Although this concept is catchy, many challenges have been encountered, specifically in the elaboration of water soluble and easy functionalizable cryptophane derivatives. The work presented in this thesis aims at developing a new straightforward approach to synthesize water soluble cryptophane sensors. These cages are based on cryptophane-[223] derivatives that bear a central carboxylic acid function to selectively graft a sensing unit, and six water soluble precursors on the cryptophanes’ rims. Using these platforms, three different water soluble sensors have been elaborated. These sensors have been characterized by 129Xe NMR spectroscopy to assess their binding properties and responsiveness. An additional aspect of these derivatives is their ability to undergo a solvent-dependent “self-encapsulation” phenomenon. This is characterized by the inclusion of the central functionality grafted on the propelendioxy linker towards the inner cavity of cryptophanes. This phenomenon has been clearly proved by 1H NMR and IR spectroscopy. The effect on the overall chiroptical properties was also investigated by polarimetry, VCD and ECD spectroscopy.

Measurement of circulating protein biomarkers associated with disease can facilitate early detection, help guide treatment strategies and improve patient outcomes beyond current standards of care. The combination of inexpensive 3D-printed flow cells and electrochemical biosensors has recently emerged as a viable platform for low-cost, reliable biomarker measurements. Here, we report an electrochemical immunoassay system based on simple graphite electrode arrays, 3D-printed flow cells, and signal-generating magnetic bead bioconjugates for simultaneous detection of three biomarker proteins (cancer antigen 125 (CA-125), midkine (MK) and osteopontin (OPN)) associated with pediatric soft tissue sarcomas (PSTS). Magnetic bead bioconjugates are functionalized with large amounts of antibody and enzyme labels, electrode arrays are modified with gold nanoparticles and antibodies for specific capture of bioconjugate-labeled biomarkers, and 3D-printed flow cells facilitate their amperometric detection. Using this system, detection limits for CA-125, OPN and MK are 100 times lower than those obtained with commercial enzyme-linked immunosorbent assay (ELISA).

Master’s thesis contains information about the enzymes, biosensors, enzyme biosensors and magnetic particles. Cholinesterasa (ChE) is the generally name for the two related enzymes, mutually differing appearance and biological functions. Acetylcholinesterasa (AChE) is necessary for the transmission of nervous excitement. AChE is located at cholinergic synapses, where is the hydrolysis of the neurotransmitter acetylcholine and this termination by the nervous excitement. Butyrylcholinesterasa (BChE) is related to AChE and it is present in serum. Experimental part was focused on electrochemical biosensors with cholinesterase enzyme using magnetic particles for reversible reconstruction layer. Cholinesterase immobilization was carried out on the magnetic particles by covalent binding after glutaraldehyde activated. The measurement of activity take place with acetylthiocholin as a substrate in a flow system, magnetic particles were captured before the platinum electrode and produced by thiocholin is detected amperometric. The aim was to measure inhibition of AChE. Significant inhibition ChE is caused by certain drugs and pesticides based on organophosphates. There was tested by inhibition of AChE pesticide dichlorvos. Emphasis was on finding possible experimental conditions for the creation of the automated procedure to measure the AChE activity, which was based on auto-injector and pumps of Gilson, together with a 735 programme for the definition of the working configuration, preparation of measurement scripts and implementation of application methods.

L’étude, la détection et l’identification de pathogènes est une problématique majeure pour la sécurité alimentaire et la médecine. Cependant, les pathogènes bactériens présents à de faibles concentrations nécessitent souvent une période de plus de 36h pour être identifiés par les méthodes standards. Ce délai est extrêmement contraignant pour des domaines où la rapidité du diagnostic est un facteur clé. Il y a donc une forte demande pour le développement d’outils pour mieux comprendre le comportement bactérien et ainsi développer des techniques de détection plus rapides et plus performantes.Les systèmes d’imagerie SPR sont largement utilisés pour l’analyse d’interactions moléculaires, car ils permettent une mesure en parallèle, en temps réel et sans marquage, tout en étant faciles d’utilisation et compatibles avec des milieux complexes. Cette technique a montré son efficacité pour l'étude et la détection de bactéries en utilisant les interactions moléculaires avec les anticorps, mais les délais de détection restent pénalisants.Dans ce contexte, un nouveau système d’imagerie permettant l’étude et la détection spécifique de pathogènes bactériens performant est développé en mettant à profit les avancées récentes en imagerie SPR optimisée en résolution. Notre système permet d'améliorer les temps de détection de pathogènes en milieux modèles grâce à sa capacité à détecter des bactéries individuelles. Il peut également être utilisé pour l'étude de l'interaction entre bactéries et surfaces spécifiques. Des premiers tests montrent que notre instrument est capable de caractériser le comportement bactérien de plusieurs souches bactériennes en interaction avec des surfaces fonctionnalisées par des espèces chimiques différentes / The study, detection and identification of pathogens is a major issue for food safety and medicine. However, bacterial pathogens present at low concentrations often require a period of more than 36 hours to be identified by standard methods. This delay is extremely constraining for areas where rapid diagnosis is a key factor. There is therefore a strong demand for the development of tools to better understand bacterial behavior and thus develop faster and more efficient detection techniques.SPR imaging systems are widely used for the analysis of molecular interactions, as they allow parallel, real-time and unlabeled measurement, while being easy to use and compatible with complex media. This technique has proven effective in the study and detection of bacteria using molecular interactions with antibodies, but detection times remain penalizing.In this context, a new imaging system allowing the study and specific detection of high-performance bacterial pathogens is being developed, taking advantage of recent advances in SPR imaging optimized in resolution. Our system improves pathogen detection times in model environments through its ability to detect individual bacteria. It can also be used to study the interaction between bacteria and specific surfaces. Initial tests show that our instrument is capable of characterizing the bacterial behaviour of several bacterial strains in interaction with surfaces functionalized by different chemical species.

Title: Multifunctional biomolecular assemblies for parallelized analysis of biomolecular interactions Author: Markéta Bocková Department / Institute: Institute of Physics, Charles University Supervisor of the doctoral thesis: Prof. Jiří Homola, Ph.D., DSc., Institute of Photonics and Electronics, The Czech Academy of Sciences Abstract: Surface plasmon resonance (SPR) biosensors represent the most advanced optical method for the direct, real-time monitoring of biomolecular interactions without the need for labelling. This doctoral thesis aims to advance the SPR biosensor method and to expand its utility in the investigation of biomolecular interactions. This encompasses activities on two major fronts of SPR biosensor research - immobilization methods and biosensing methodologies. Methods for the immobilization of biomolecules were researched with the aim of enabling the immobilization of a broad range of biomolecules on the SPR biosensor surface in a spatially controlled manner. The development of novel biosensing methodologies was pursued in order to address the current limitations of SPR biosensors associated with non-specific adsorption and limited analyte transport, and thus to improve the accuracy and robustness of SPR biosensor measurements. Finally, advances in the development of immobilization...

In this work, a chemiresistor-type sensing platform based on aligned arrays of nitrogen-doped multi-walled carbon nanotubes (N-MWCNTs) was developed. Our N-MWCNT based sensors can be made on both rigid and flexible substrates; they are small, have low power consumption and are suitable for highly efficient and reliable detection of different biomolecules and gases, at room temperature. The performance of these sensors was demonstrated for avian influenza virus (AIV) subtype H5N1 DNA sequences and toxic gases NO and NH3 at low concentrations. In our study, chemical vapor deposition (CVD) method was applied to synthesize vertically aligned nitrogen doped carbon nanotube arrays on a large area (> 1 cm2) on Si/SiO2 substrate using Fe/Al2O3 layer as a catalyst and a mixture of ethanol and acetonitrile as a C/N source. Especially, the diameter, length, nitrogen-doping concentration and morphology of the nanotubes were controllably tailored by adjusting the thickness of catalyst film, reaction duration and temperature as well as the amount of nitrogen-containing precursor. For integrating N-MWCNTs into chemiresistor devices, we developed a direct contact printing method for a dry, controllable and uniform transferring and positioning of the CVD-grown vertical nanotubes onto well-defined areas of various rigid and flexible substrates. After horizontally aligned N-MWCNT arrays were formed on a target substrate, interdigitated metallic microelectrodes with an interspacing of 3 µm were deposited perpendicular to the nanotube alignment direction to fabricate chemiresistor devices for biomolecule and gas sensing. This way, well-aligned nanotubes were laid across the Au/Cr interdigitated electrode fingers, had a strong adhesion with the electrodes and served as conducting channels bridging the electrodes. The N-MWCNT based chemiresistor device was applied as a label-free DNA sensor for a highly sensitive and fast detection of AIV subtype H5N1 DNA sequences. For this, the nanotubes were functionalized with probe DNA, which was non-covalently attached to sidewalls of the N-MWCNTs via π-π interaction. Such functionalized sensors were applied to quantitatively detect complementary DNA target with concentration ranging from 20 pM to 2 nM after 15 min incubation at room temperature. The sensors showed no response to non-complementary DNA target for concentrations up to 2 µM showing an excellent selectivity. Investigations on the efficient gas sensing of N-MWCNT-based chemiresistor of reducing/ oxidizing gases NH3 and NO were also reported in this work. The aim was to assess the possibility for N-MWCNTs to be applied as innovative sensing materials for room temperature gas sensing. N-MWCNTs with varying doping levels (N/C ratio of 5.6 to 9.3at%) were used as sensing materials and exposed to NH3 (1.5-1000 ppm) and NO (50-1000 ppm) for exploring and comparing their sensing performance. This study offered an effective route for further modification of CNTs according to various sensing application. Finally, our investigations showed a high potential of the developed N-MWCNT-based sensing platform for various applications ranging from environmental monitoring to point-of-care medical diagnostics.

The semiconductor industry was benefited by the advances in technology in the last decades. This fact has an impact on the sensors field, where the simple transducer was evolved into smart miniaturized multi-functional microsystems. However, commercially available gas and biological sensors are mostly bulky, expensive, and power-hungry, which act as obstacles to mass use. The aim of this work is gas and biological sensing using capacitive structures. Capacitive sensors were selected due to its design simplicity, low fabrication cost, and no DC power consumption. In the first part, the dominant structure among interdigitated electrodes (IDEs), fractal curves (Peano and Hilbert) and Archimedean spiral was investigated from capacitance density perspective. The investigation consists of geometrical formula calculations, COMSOL Multiphysics simulations and cleanroom fabrication of the capacitors on a silicon substrate. Moreover, low-cost fabrication on flexible plastic PET substrate was conducted outside cleanroom with rapid prototyping using a maskless laser etching. The second part contains the humidity, Volatile Organic compounds (VOCs) and Ammonia sensing of polymers, Polyimide and Nafion, and metal-organic framework (MOF), Cu(bdc)2.xH2O using IDEs and tested in an automated gas setup for experiment control and data extraction. The last part includes the biological sensing of C - reactive protein (CRP) quantification, which is considered as a biomarker of being prone to cardiac diseases and Bovine serum albumin (BSA) protein quantification, which is used as a reference for quantifying unknown proteins.

La tuberculose (TB) est une maladie transmise par l'air causée par Mycobacterium tuberculosis (MTB) qui affecte habituellement les poumons, entraînant une toux sévère, de la fièvre et des douleurs thoraciques. En 2015, il a été estimé que plus de 9,6 millions de personnes dans le monde ont développé la tuberculose et que 1,5 millions sont morts de la maladie infectieuse dont 12% étaient co-infectés par le virus de l'immunodéficience humaine (VIH). En 2016, les statistiques ont atteint un total de 1,7 million de personnes décédées de la tuberculose avec environ 10,4 millions de nouveaux cas de TB diagnostiqués dans le monde. Le développement de systèmes de mesures rapides et fiables, ultra-sensibles, bon marché et facilement disponibles est essentiel pour lutter contre la tuberculose (TB) et la tuberculose multirésistante. Ce travail est une étude sur la faisabilité d'une part d'immunocapteurs électrochimique utilisant un antigène spécifique de Mycobacterium tuberculosis Ag85B pour détecter la tuberculose et d'autre part de biocapteurs utilisant l'enzyme cytochrome P450-2E1 (CYP2E1) pour détecter les médicaments antituberculeux dans le sérum ou l’eau.L'immunocapteur a été développé en adoptant la méthode ELISA indirecte qui a été utilisée pour la détection des anticorps IgG dans les tests ELISA IgG contre la tuberculose. Il a été réalisé en électrodéposant par voltamétrie cyclique (CV) d’abord de l'acide polyamique (PAA) sur une électrode de carbone vitreux (GCE) puis des antigènes recombinants de Mycobacterium tuberculosis Ag85B (Ag). Les électrodes modifiées ont été caractérisées par CV et SWV. Le profil de réponse de l'immunocapteur à des anticorps de Mycobacterium tuberculosis a été étudié par SWV et la réponse linéaire était dans une gamme de 0,3 à 1,6 mg / mL avec une limite de détection (LOD) de 0,08 mg / mL.D'autre part, deux plates-formes pour le développement de biocapteurs pour la détection de médicaments antituberculeux, l'éthambutol (ETH) et la rifampicine (RIF), ont également été préparées. L’une était un composite PAA/AgNPs (nanoparticules d’argent) déposé par goutte sur GCE pour former une plate-forme GCE/PAA/AgNPs. Alors que l'autre plate-forme (GCE/PPy/AgNPs) a été formée par électrodéposition de pyrrole en présence de nanoparticules d'argent (PPy + AgNPs) sur GCE en utilisant la chronopotentiométrie. Les plateformes GCE/PAA/AgNPs et GCE/PPy/AgNPs ont ensuite été caractérisées en utilisant la voltamétrie cyclique alors que leurs morphologies l’ont été par microscopie à force atomique (AFM) et microscopie électronique à balayage (MEB). L'immobilisation de l'enzyme cytochrome P450-2E1 (CYP2E1) sur les deux plates-formes a été réalisée par dépôt de gouttes. L'efficacité des biocapteurs GCE/PAA/AgNPs/CYP2E1 et GCE/PPy/AgNPs/CYP2E1 pour la détection de ETH et de RIF a été étudiée par DPV. Le biocapteur GCE/PPy/AgNPs/CYP2E1 a été capable de détecter les médicaments antituberculeux à leur concentration sérique maximale (2 à 6 μg/mL). Alors que le biocapteur GCE/PAA/AgNPs/CYP2E1 était capable de détecter l'ETH à des concentrations inférieures au taux sérique (2,5 ng/mL à 12,5 ng/mL). Par conséquent, le biocapteur GCE/PAA/AgNPs/CYP2E1 a la capacité de détecter ETH même à l'état de traces dans les systèmes aqueux. Ainsi, le biocapteur GCE/PAA/AgNPs/CYP2E1 a une limite inférieure de détection de l'ETH (0,75 ng/mL) par rapport au biocapteur GCE/PPy/AgNPs/CYP2E1 (1,3 µg/mL). La sensibilité du biocapteur GCE/PAA/AgNPs/CYP2E1 pour l'ETH était de 5 µA/ng.mL-1 alors que celle du biocapteur GCE/PPy/AgNPs/CYP2E1 était de 2,6 µA/µg.mL-1. Le biocapteur GCE/PPy/AgNPs/CYP2E1 était le seul biocapteur capable de détecter le RIF avec une limite de détection de 7,5 µg/mL. Le biocapteur GCE/PPy/AgNPs/CYP2E1 convient à la détection de l'ETH et du RIF aux taux sériques et aux systèmes aqueux. Alors que le GCE/PAA/AgNPs/CYP2E1 ne convient que pour la détection des médicaments antituberculeux à des niveaux traces dans l'eau. / Tuberculosis (TB) is an airborne disease caused by Mycobacterium tuberculosis (MTB) that usually affects the lungs leading to severe coughing, fever and chest pains. In 2015 it was estimated that over 9.6 million people worldwide developed TB and 1.5 million died from the infectious disease of which 12 % were co-infected with human immunodeficiency virus (HIV). In 2016 the statistics increased to a total of 1.7 million people died from TB with an estimated 10.4 million new cases of TB diagnosed worldwide. The development of the fast and reliable point-of-care systems that are ultra-sensitive, cheap and readily available is essential in order to address and control the spread of the tuberculosis (TB) disease and multidrug-resistant tuberculosis. This work is the feasibly study on one part on the development of electrochemical immunosensor using a specific Mycobacterium tuberculosis Ag85B antigen to detect tuberculosis and on another part on the development of biosensors using cytochrome P450-2E1 (CYP2E1) enzyme to detect anti-TB drugs in aqueous systems. The immunosensor was developed by adopting the indirect ELISA method which was used for the detection of the IgG antibodies using the tuberculosis IgG ELISA. The development of immunosensor was achieved using glassy carbon electrode (GCE) modified with polyamic acid (PAA) in which Mycobacterium tuberculosis recombinant antigen Ag85B (Ag) was immobilized. PAA was electrodeposited on glassy carbon electrode (GCE) using cyclic voltammetry. The modified electrodes were characterized by cyclic and square wave voltammetry. The response profile of the immunosensor at Mycobacterium tuberculosis antibodies was studied by square wave voltammetry and the linear response was in a range of 0.3 to 1.6 mg/mL with a detection limit (LOD) of 0.08 mg/mL. On the other hand, two platforms for the development of biosensors for the detection of ethambutol and rifampicin (anti-TB drugs) were also prepared. Two platforms were prepared whereby polyamic acid-silver nanoparticles composite (PAA/AgNPs) was drop-coated on GCE to form GCE/PAA/AgNPs platform. While the other platform (GCE/PPy/AgNPs) was formed by electrodeposition of polypyrrole-silver nanoparticles composite (PPy/AgNPs) on GCE using chronopotentiometry. The GCE/PAA/AgNPs and GCE/PPy/AgNPs platforms were then characterized using cyclic voltammetry while their morphologies were obtained by atomic force microscopy (AFM) and scanning electron microscopy (SEM). The immobilization of cytochrome P450-2E1 enzyme (CYP2E1) on both platforms was achieved by means of drop coating. The efficiency of the GCE/PAA/AgNPs/CYP2E1 and GCE/PPy/AgNPs/CYP2E1 biosensors for the detection of ethambutol (ETH) and rifampicin (RIF) was studied by differential pulse voltammetry (DPV). The GCE/PPy/AgNPs/CYP2E1 biosensor was able to detect anti-TB drugs at their peak serum levels (2 – 6 µg/mL). Whereas the GCE/PAA/AgNPs/CYP2E1 biosensor was able to detect ethambutol at concentrations lower than the serum level (2.5 ng/mL to 12.5 ng/mL). Therefore, GCE/PAA/AgNPs/CYP2E1 biosensor has an ability to detect ethambutol even at trace levels in aqueous systems. Thus, the GCE/PAA/AgNPs/CYP2E1 biosensor have lower limit of detecting ETH (0.75 ng/mL) than GCE/PPy/AgNPs/CYP2E1 biosensor (1.3 µg/mL). The sensitivity of GCE/PAA/AgNPs/CYP2E1 biosensor for ETH was 5 μA/ng.mL-1while the sensitivity of GCE/PPy/AgNPs/CYP2E1 biosensor was 2.6 μA/μg.mL-1. The GCE/PPy/AgNPs/CYP2E1 biosensor was the only biosensor that was able to detect RIF with a limit of detection of 7.5 µg/mL. The GCE/PPy/AgNPs/CYP2E1 biosensor is suitable for the detection of ETH and RIF at serum levels and aqueous systems. While the GCE/PAA/AgNPs/CYP2E1 is suitable for only detecting anti-TB drugs at trace levels in water.

Identifying and detecting health hazards in food products, especially contaminants and toxic substances such as allergens, food toxins and agricultural residues from pesticides, remains a challenge. Increasing demand for food products and growing health consciousness necessitate rapid and accurate measurements which can be easily conducted on-site without long measurement times and high costs. Due to their ease of use, accuracy sample preparation and rapidity, biosensors have started to outcompete time-consuming lab-scale analytical devices. However, as the use of biosensors increase, a concern of the amount of plastics and synthetic polymers used in the fabrication of these biosensors rises. In this dissertation, new ways to create biodegradable and eco-friendly plant-based SERS biosensor platforms from corn protein, zein, are presented. Its higher hydrophobicity and film forming capability make zein a very suitable biopolymer for fabricating biosensors. In the first part of this dissertation, chemical crosslinking was tested to improve the surface hydrophobicity, surface roughness (using AFM), mechanical properties, kinetics of gelation and film formation of zein films, and as a result zein-film based SERS platforms with fewer defects could be fabricated. In the second part, the detection sensitivity of the zein film-based SERS platforms was increased with metallic nanoparticle decoration (gold, silver or silver-shelled-gold). The addition of all three types of nanoparticles significantly increased the SERS enhancement factors of the platforms, with silver-shelled-gold nanoparticles giving the highest enhancement factor of 10⁵. In the last part of this thesis, a novel approach was tested, where electrospun zein nanofibers decorated with metallic nanoparticles were used as a SERS biosensor platform. Due to their higher surface area-to-volume ratios, electrospun zein nanofibers gave a higher SERS enhancement factor (10⁶). This enhancement factor enabled the detection of acrylamide, a food carcinogen, with a 10⁴ times lower detection limit than nanophotonic based nanoimprinted zein, acrylamide sensor platform. Overall, this dissertation successfully shows the fabrication of biodegradable and eco-friendly SERS sensor platforms that have comparable detection sensitivities to those of non-biodegradable ones.