Physical Sciences and Mathematics Commons^™

The Stability Study Of Dna-Polymer Hybrids For Nanotechnology Applications, Ethan Kuehn, Milan Jebaraj

Miners Solving for Tomorrow Research Conference

DNA nanostructures have garnered increasing interest in their application as drug delivery vehicles. However, DNA is susceptible to degradation under physiological conditions. To remedy this, we have devised a novel method to coat DNA nanostructures with the polysaccharide chitosan (a natural derivative of chitin). Chitosan binds to DNA electrostatically and inhibits nuclease activity that would normally degrade DNA in a physiological environment. We used both agarose gel electrophoresis (AGE) and atomic force microscopy (AFM) to determine the stability of DNA before and after immersion in a simulated biological environment. Physiological conditions were mimicked by incubating the DNA in cell culture …

The Effects Of Preventing Dephosphorylation Of Lqg1 On Cytokinesis, Jenna Mueller

Miners Solving for Tomorrow Research Conference

Iqg1 plays crucial roles in cytokinesis, including the assembly, contraction, and disassembly of the actomyosin ring, as well as the coordination of contraction and septation. Given that cytokinesis must occur post-mitosis, Iqg1 is regulated by the cell cycle. This study explores hypotheses regarding Iqg1 regulation: it’s binding to action is negatively influenced by the cyclin-dependent kinase (CDK) Cdc28 and positively influenced by dephosphorylation via Cdc14. Newly developed yeast degron tagged strains allow for rapid depletion of specific proteins. Iqg1 mutations that alter serine to threonine, which allows phosphorylation but not dephosphorylation, in the degron strain allow testing of mutant phenotypes. …

Asphalt Pavement Rejuvenation Investigated By Nuclear Magnetic Resonance Relaxometry, Catherine Skaggs

Miners Solving for Tomorrow Research Conference

Asphalt is a relatively inexpensive material commonly used for road pavements; however, asphalt ages from exposure to oxygen and UV radiation, leading to loss of elasticity, which leads to cracks and potholes. To slow or reverse asphalt aging, pavement preservation treatments are in use. It’s unclear whether these treatments truly rejuvenate the pavement structure or merely offer a short-term benefit. Nuclear Magnetic Resonance (NMR) relaxometry is an analytical technique that uses the recovery of excited nuclear magnetization as a parameter to gain insights into molecular environments. Recovery-time distributions gathered from asphalt materials show differences between regular and rejuvenated asphalt samples, …

Bis(Μ-1,4-Dihydropyridin-4-One-Κ2o:O)Di-Μperchlorato-Κ4o:O0-Bis[Aqua(1,4-Dihydropyridin-4-One-Κo)Copper(Ii)] Tetraaquabis(1,4-Dihydropyridin-4-One-Κo)Copper(Ii) Tetrakis(Perchlorate) 1,4-Dihydropyridin-4-One Disolvate, Mark M. Turnbull, Christopher Landee, Jan L. Wikaira

Chemistry

The reaction of copper(II) perchlorate hexahydrate with 4-pyridone and pyrazine in 1-propanol serendipitously yielded crystals of the solvated title double salt, [Cu(C5H5NO)2(H2O)4][Cu2(ClO4)2(C5H5NO)4(H2O)2](ClO4)4·2C5H5NO, as a biproduct. The copper cations in both the monometallic complex and the dimeric species exhibit classic Jahn-Teller-like elongations. All coordinating 4-pyridone molecules are in the κ-O coordination mode. The dimeric component exhibits both bridging 4-pyridone and perchlorate ligands. Both complexes and the 4-pyridone molecules are bound together by a network of classical hydrogen bonds. The non-coordinating perchlorate ions were modeled as three-site disordered and one of the coordinating 4-pyridone molecules was modeled as two-site disordered. © 2026 …

Non-Redundant Rovibrational Hamiltonians By Molien Generating Functions And Gröbner-Basis Reduction, Leandro Ajo

University Libraries Undergraduate Research Award

High-resolution molecular spectroscopy requires an effective Hamiltonian whose operator content is both complete, containing every term allowed by molecular symmetry and nonredundant, free of any algebraically dependent operators that would cause ill-conditioned parameter fits. Traditional derivations based on Van Vleck contact transformations satisfy neither criterion automatically. This paper develops a rigorous, algorithmic pipeline that guarantees both properties simultaneously. Starting from the permutation– inversion (PI) group GPI of a molecule (Longuet-Higgins, 1963), we apply Molien’s theorem (Molien, 1897) to the symplectic normal-coordinate representation to obtain the vibrational generating function Φvib(t); integrate over the Haar measure of SO(3) (Weyl, 1946) to obtain …

Designing A Novel Inhibitor For Cobalamin-Independent Methionine Synthase, Damon Virgo

Undergraduate Honors Papers

Microbial infections are some of the leading causes of death in the population at large, and antimicrobial-resistant “superbugs” have become a growing issue, so there is a great need to explore new and alternative pathways for fighting these diseases. One method for doing this is by exploring Methionine synthase (MetSyn), which plays a critical role in cellular one-carbon metabolism, catalyzing the methylation of homocysteine to form methionine, an essential amino acid required for protein synthesis and methyl group transfer reactions. Key differences between the B12-independant fungal MetSyn enzyme and the B12-dependant mammalian form can allow for selective targeting of the …

Dendrimer Nanogels With Built-In Free Radical Scavenging Enable Efficient Topical Delivery Of A Hydrophilic Antioxidant To Restore Lens Redox Balance For Cataract Treatment, Lin Qi, Huari Kou, Anna Chernatynskaya, Da Huang, Vimalin Jeyalatha Mani, Humeyra Karacal, Nuran Ercal, Hu Yang

Chemistry Faculty Research & Creative Works

Cataract is a leading cause of vision impairment worldwide and are primarily caused by oxidative stress that damages and aggregates lens proteins, leading to lens opacification. However, the eye's anatomical barriers limit the penetration and bioavailability of antioxidant therapies. To address this challenge, a dendrimer-based nanogel with a built-in reactive oxygen species (ROS)-scavenging capability developed by us was employed to deliver the antioxidant N-acetylcysteine (NAC) to the lens. NAC was loaded into a generation-5 PEGylated poly(amidoamine) dendrimer (G5-PEG-TK, termed the GPT) nanogel. The resulting NAC-GPT was characterized for its ROS-scavenging activity, bioavailability, and corneal permeability. The efficacy of NAC-GPT was …

Co-Ordination Driven Heteroleptic Self-Assembly Of Naphthalene Diimide And Aromatic Dicarboxylate, Rosanna Jees, Kennedy Kuchta, Joshua Do, Erendra Manandhar

Posters - 2026

Co-ordination driven self-assembly is a powerful tool to construct supramolecular co-ordination complexes (SCCs) with predictable and well-defined molecular structures. Fujita, Stang, Newkome, & others have developed novel methodology to synthesize 2D & 3D Metallo-supramolecular structures, such as triangles, cubes, and octahedrons. These have potential applications for optical materials, sensing, catalysis, light harvesting & emissions due to the structures’ well-defined cavity and easy functionalization at the periphery position of ligands.1–4 SCCs with various functional groups, fluorophores, and chromophores, like crown ethers, carbazoles, fullerenes, and dendrimers, have been reported through self-assembly, yet naphthalene-diimide (NDI)-based macrocycles and cages are limited. This project focuses …

Synthesis Of Copper-Phenanthroline Complexes: A Solvothermal-Compatible Approach For The Exploration Of Metal Complexes, Yunping Zhoujin, Michael Anim Safo, Navindra Keerthisinghe, Mark D. Smith, Sophya Garashchuk, Hans Conrad Zur Loye

Faculty Publications

Inorganic–organic hybrid materials have been widely investigated for their applications in catalysis, optics, magnetism, and biomedicine. Copper halide complexes are of particular interest due to their structural diversity and physicochemical properties. Conventional crystal growth approaches, such as slow evaporation and hydro(solvo)thermal synthesis, typically require extended reaction times and often favor thermodynamically stable phases. In this study, we prepared ten copper-phenanthroline halide (X = Cl, Br, and I) complexes using both traditional hydrothermal reactions and microwave-assisted hydrothermal methods and obtained [CuI(C₁₂H₈N₂)₂][I₃], [C₁₂H₉N₂][CuI₂]·(H_{2 …}

Steric And Electronic Considerations Of Ester Hydrolysis: Updating A Longstanding Physical Organic Kinetics Experiment, Mara J. Aucoin

Chemistry Theses

A current, longstanding undergraduate physical chemistry kinetics experiment uses UV-Vis spectrophotometry to follow the hydrolysis of para-nitrophenyl acetate (NPA) with an imidazole (Im) catalyst. The catalyzed and uncatalyzed reaction paths can be studied simultaneously under pseudo first order conditions ([Im]>>>[NPA]). To obtain the rate constants for the catalyzed and uncatalyzed reactions, the concentration of imidazole is varied between reactions and then plotted against the observed rate constant (k_obs).This produces a linear line where the slope is equal to the rate constant of the catalyzed reaction (k_cat) and the intercept is equal to …

Targeting Oncogenes: Development And Characterization Of Aurka And Her2 Inhibitors, Itzel Montoya

Chemistry Theses

Targeted inhibition of oncogenes has remained a key strategy in the development of more potent, effective, and less toxic therapeutic anticancer agents. Among the most clinically significant signaling pathways are those mediated by the Human Epidermal Growth Factor Receptor 2 (HER2) and Aurora Kinase A (AurKA). HER2 is a member of the ErbB receptor family that supports cell growth and proliferation through downstream signaling of the PI3K and MAPK pathways and is closely linked to more aggressive tumors and therapeutic resistance. AurKA is a protein kinase essential for mitotic spindle assembly, centrosome maturation, and other key processes in cell cycle …

Folic Acid–Carbon Dot–Gemcitabine Nanoparticles For Targeted Cancer Drug Delivery, Irfan Huda, Hua Mei

SPARK Symposium Presentations

This project aims to develop a folic acid-attached carbon dot nanoparticle system (FA-CDs-GEM) for the targeted delivery of gemcitabine to cancer cells. While gemcitabine is widely used, its effectiveness is limited because a short in vivo half life and lack of selectivity, which lead to severe side effects. Carbon dots offer a simple and modifiable platform as the drug delivery and bioimaging agent. Conjugation of folic acid to the carbon dots enables selective targeting of cancer cells that overexpress folate receptors. In this study, we synthesized and characterized FA-CD-GEM nanoparticles and developed an HPLC calibration curve of GEM to accurately …

Competitive Reaction Pathways In The Fully Green Synthesis And Surface Modification Of Silver Nanowires Under L-Ascorbic Acid-Limited Conditions, Finley Neal

Honors Theses

Silver nanowires (AgNWs) are critical building blocks for transparent conductive films (TCFs) in flexible electronics, yet their commercial viability is hindered by environmentally hazardous, energy-intensive synthesis methods and limited intrinsic chemical stability. This study investigated a fully green, room-temperature (25℃) batch synthesis of pristine AgNWs using tannic acid as a biodegradable dual reducing and capping agent under strict kinetic pH control (pH 1.25). To enhance oxidative resistance, a subsequent surface modification protocol was evaluated to deposit a protective palladium (Pd) shell using L-ascorbic acid (LAA) as a secondary reducing agent. The pristine green synthesis yielded one-dimensional Ag nanostructures with a …

Synthesis Of Piperidine Heterocycles With Specific Functional Groups Via Sn2 Reactions, Teyanna Monroe

Honors Theses

Piperidine is a heavily utilized nitrogen containing heterocycle found in numerous pharmaceutical agents, solidifying its importance as a building block in drug development. The focus of this research is to investigate different mechanisms of action for adding and replacing various functional groups utilizing readily available lab materials. These findings would lead to determining the overall influence of substitution patterns and functional groups have on stereochemistry, reactivity, and overall conformation of the piperidine ring. The synthetic approach involves the formation of 3-bromo-5-methoxy-tosylpiperidine intermediate through acid promoted cyclization, followed by nucleophilic substitution reactions to introduce various functional groups. Reaction progress and product …

Synthesis And Characterization Of Metal Complexes Of Oxindole-Based Β-Lactams, Kenya Rosas, Erick Morales Orrante, Carlos Sifuentes, Alexsei Nazarov

Posters - 2026

• β-lactams are essential structural components of many antibiotics and widely studied due to their biological importance and synthetic versatility.
• The Ugi reaction is a multicomponent reaction, involving a primary amine, carboxylic acid, isocyanide, and an aldehyde or a ketone, that rapidly generates α-acetamido carboxamide derivatives (Ugi adducts).
• The synthesis and characterization of four oxindole-based β-lactam derivatives:
  • 1-Benzyl-N-(tert-butyl)-2-oxo-3-(2-oxoazetidin-1-yl)indoline-3-carboxamide (4a).
  • N-(tert-butyl)-2-oxo-3-(2-oxoazetidin-1-yl)-1-phenylindol-3-carboxamide (4ab).
  • N-(tert-Butyl)-2-oxo-3-(2-oxoazetidin-1-yl)indoline-3-carboxamide (4d).
  • N-(tert-butyl)-1-methyl-2-oxo-3-(2-oxoazetidin-1-yl)indol-3-carboxamide (4e).
• The coordination of the four Ugi adducts with Cu (II) and Ni (II) at different pH points to enhance their stability and improve biological activity.

2026 Research Day Program, Lincoln Memorial University

Research Day

This program contains abstracts and presentation summaries from LMU's 2026 Annual Research Day conference.

Synthesis And Photophysical Studies Of Coumarin-Quinoline Derivatives, Nishrenika Pokhrel

Honors Theses

A new family of oxime-functionalized coumarin-quinoline derivatives, 5a and 5b, has been synthesized through a five-step procedure in high yields (45-98%). Compound 5a is designed as the sensing probe, while 5b serves as a model system to support mechanistic understanding. The sensing approach is based on the reactivity of the oxime group, which can undergo phosphorylation in the presence of organophosphate nerve agents. Based on this behavior, it is hypothesized that 5a can react irreversibly with a nerve agent mimic. The structures were fully characterized by NMR, FTIR, and HRMS. Photophysical properties of 5a were studied in various solvents, …

Serendipitous Reactivity Of Tripodal Tris(Nitroxide) Aluminum And Gallium Complexes With Halomethanes, Elizabeth N. S. Ting , '26

Senior Theses, Projects, and Awards

The development of new strategies for bond activation remains an important goal in chemistry. Element-ligand cooperative (ELC) chemistry using abundant main-group elements has emerged as a promising strategy for enabling bond activation without relying on traditional transition-metal redox chemistry. In this work, the reactivity of Group 13 complexes supported by a tripodal tris(nitroxide) ligand, (TriNOx^3-)M (M = Al (1), Ga (2); TriNOx^3- = [{(2^tBuNO)C₆H₄CH₂}₃N] ^3-), was investigated toward halomethanes. This reactivity leads to the formation of the ligand-protonated metal halide species (HTriNOx^2-)M–X. To support …

Synthesis And In Vitro Evaluation Of Potential Tuberculosis Antibiotics, Chloe Spradlin

Honors Projects

Tuberculosis (TB) remains a major global health threat. The bacteria causing TB, Mycobacterium tuberculosis, has proven difficult to combat, as drug resistance (MDR-TB) continues to develop within the bacteria. Access to healthcare in developing countries complicates the treatment of TB and MDR-TB. The World Health Organization has declared TB a global health crisis and has called for the development of new therapies. Previously, we used AutoDock Vina software to design novel drugs targeting InhA, an enzyme involved in mycobacterial cell wall synthesis. This project focuses on synthesizing amino diphenyl amides (ADA) and screening them against Mycobacterium. The synthetic pathway enables …

Designing Surface-Induced Entatic States In Copper Complexes For Tunable Reactivity, Rachel Kiser

Senior Theses

Copper catalysts play an important role in electrocatalytic oxidation reactions due to their redox flexibility and relative abundance compared to noble metal catalysts. In biological systems, copper metalloenzymes often achieve enhanced reactivity through an entatic state. Entasis is described as an active site or metal center being constrained to a geometric and electronic state, minimizing primary sphere reorganization energy and achieving higher rates of electron transfer.  This study investigates whether entasis can be achieved in synthetic molecular catalysts by immobilizing Cu(I) complexes onto metal oxide surfaces. Two Cu(I) complexes bearing carboxylate-functionalized ligands were examined both in homogeneous solution and when …

Crystallization And Utility Of Brominated Phenylethynylene Bis-Urea Macrocycles, Paras Srivastava

Senior Theses

Macrocycles are large, cyclic molecules with central cavities that can encapsulate other molecules and that have uses in supramolecular chemistry. The Shimizu group has previously synthesized Macrocycle 1, a phenylethynylene bis-urea macrocycle that crystallizes in a columnar form, enabling its utility as a host in host-guest systems. Reactions within these systems can be used to modify stereospecificity, kinetics, and other physical properties. Previously, photodimerization reactions between coumarins and chromones have been studied in systems of Macrocycle 1, resulting in the improved specificity of photodimerization products. Herein, we apply a dynamic covalent chemistry (DCC) strategy to synthesize Macrocycle 1 and its …

Radicals Transforming Organic Matter: Implications For Non-Pyrogenic Black Carbon And Nitrogen Formation, Molecular Dynamics In Tropical Soils, And Lignin Valorization, João Vitor Dos Santos

Chemistry & Biochemistry Theses & Dissertations

Radicals drive the transformation of organic matter in natural and engineered systems, altering its structure, reactivity, and stability. Condensed aromatic carbon (ConAC) and condensed aromatic nitrogen (ConAN) are among the most persistent forms of organic matter in soils and are traditionally interpreted as products of biomass burning. This dissertation challenges the long-standing assumption that these materials are exclusively pyrogenic, showing that iron-mediated radical chemistry can generate condensed aromatic structures under ambient conditions.

Chapters II and III show that Fenton-like radical oxidation of lignin-rich biomass produces condensed aromatic structures compositionally similar to pyrogenic black carbon and black nitrogen when assessed with …

Quantifying Nutrient Fluxes Across The Sediment-Water Interface In The Lafayette River Estuary, Adriana E. Amrhein

OES Theses and Dissertations

The Lafayette River, a shallow, eutrophic tributary of the Chesapeake Bay, experiences seasonal harmful algal blooms (HABs). While management efforts focus on reducing external nutrient inputs, internal loading from benthic sediments remains poorly constrained. This study quantifies spatial and seasonal variability in nutrient and radium isotope fluxes across the sediment–water interface at three sites where HABs are known to initiate and represent contrasting sediment textures and hydrodynamic conditions. Sediment cores and porewater samples were collected in summer 2023 and winter 2024 to measure grain size, porosity, dissolved nutrients (NH₄⁺, NOₓ⁻, PO₄³⁻), and radionuclide activities (²²⁴Ra and ²²⁸Th). Radium isotope disequilibrium …

Increased Backbone Rigidity Of Artificial Transcription Factors, Jasmine Glover, Emma Otey, Joanna K. Kwao, Nicholas Truex

Senior Theses

Programming DNA-binding proteins is an effective strategy for developing therapeutics that regulate gene expression. These proteins can directly bind to DNA to activate or repress transcription of specific genes. Zinc finger proteins are a class of DNA-binding proteins commonly found in eukaryotic organisms. Their DNA-binding function is derived from unique amino acid sequences within each domain that recognizes specific nucleotides, allowing each finger to selectively recognize three DNA base pairs. Adjoining of multiple domains in tandem allows recognition of a specific DNA sequence. Artificial transcription factors can be made of multiple zinc finger domains arranged in tandem and engineered to …

Observations Of An Oscillatory Mechanochemical Reaction Between Tetrathiafulvalene And Chloranilic Acid, Alastair Deans

Physics Theses & Dissertations

Mechanochemistry is the study of chemical reactions driven by the input of mechanical en ergy in addition to thermal activation. Mechanochemical reactions from powders are carried out by manual grinding or milling using various types of ball mills, or in twin extruders. While mechanochemistry has great potential affording economically and environmentally advantageous “green” synthetic methods, a drawback is that its chemical mechanisms are not well understood. One example of such a reaction currently under study involves tetrathiafulvalene, an organic elec tron donor with two polymorphs (orange and brown), and chloranilic acid, an electron acceptor. Previous results show that neat grinding …

Biocrude From Organic Waste And Its Conversion To Hard Carbon: Experimental And Modeling Study, Isamu Umeda

Civil & Environmental Engineering Theses & Dissertations

This study establishes a technical and theoretical foundation for the efficient conversion of organic waste into biocrude and high-value carbon materials, aiming to facilitate the industrialization of hydrothermal and solvothermal liquefaction. The dissertation research is structured as follows:

Chapter 2 developed a novel chemical kinetic model for the HTL of corn stover based on elemental balances (C, H, N, and O). By incorporating temperature, residence time, solid loading as an independent variable, the model successfully predicted product yields and properties, revealing that there was non-pseudo-first-order reaction pathways in the conversion of water soluble organics in aqueous phase (AP) to hydrochar. …

Toxicity, Chemistry, And Public Health Relevance Of Emerging Nicotine Analog Vapes, Pods, And Pouches., Rhea Raghu, Mohana Sengupta, Karen Lin, Felix Effah, Robert M. Strongin, Irfan Rahman

Chemistry Faculty Publications and Presentations

Electronic nicotine delivery system manufacturers, such as Charlie's Holdings Inc., ECBlend, Outlaw, and NicRiver, have recently introduced nicotine analogs, such as 6-methyl nicotine, 6-MN ("Metatine"), and nicotinamide, NA ("Nixamide," "Nixodine," or "Nixotin-free base and salt") in products to circumvent the U.S. FDA's premarket tobacco product application (PMTA) requirements. Marketed as "tobacco-free," "PMTA-exempt," or "FDA-approved," these compounds now appear in oral nicotine pouches and disposable bars/vapes from brands such as Outlaw Dip, Kumi-Six, SBX, Katchmi, and Spree Bar under proprietary labels including "NoNic6," "Metatine," or "NIC-SAFE." These products often mimic the appeal of conventional nicotine delivery systems, with extensive use of …

Preferences For Mathematics And Science Education Majors Among Senior High School Students In Bataan, Zydrick L. Avelino

Jurnal Pendidikan Sains

This study examines the factors influencing Senior High School students’ preferences for Bachelor of Secondary Education (BSEd) majors in Bagac and Morong, Bataan, with particular focus on the low interest in Mathematics and Science specializations despite increasing demand for STEM educators. Using a descriptive quantitative design, data were collected from 369 students through a structured survey and analyzed using frequency and percentage distributions. The results reveal a strong preference for non-STEM majors, with Social Studies (42.12%) and English (35.04%) dominating, while Science (15.43%) and Mathematics (7.395%) received significantly lower interest. Personal interest emerged as the primary determinant (58.8%), followed by …

Design And In Silico Modeling Of Heterocyclic-Based Xanthone Derivatives As Potential Anticancer Agents Through Tyrosine Kinase Inhibition, Yehezkiel Steven Kurniawan, Ervan Yudha, Nela Fatmasari, Radite Yogaswara, Harno Dwi Pranowo, Eti Nurwening Sholikhah, Jumina Jumina

Makara Journal of Science

Cancer is one of the deadliest diseases nowadays, and tyrosine kinase receptors play crucial roles in cancer cell survival, differentiation, proliferation, and migration. This study designed and developed a new inhibitor from heterocyclic-based xanthone derivatives to target two tyrosine kinase receptors, epidermal growth factor receptor (EGFR) and platelet-derived growth factor receptor (PDGFR), through in silico screening. Eighteen heterocyclic-based xanthones were evaluated through molecular docking for both receptors. All heterocyclic-based xanthones gave the root mean square deviation (RMSD) value lower than 2.00 Å. Xanthone with isobenzothiazole substituent (iBzThio) was found as the most potent inhibitor with binding energies of -10.60 and …

Anthrone-Based Dummy Molecularly Imprinted Polymer For The Selective Detection Of Fluorene And Phenanthrene In Simulated River Water, Aria Pinandita, Nurrahmi Handayani, Muhammad Iqbal, Untung Triadhi, Rusnadi Rusnadi, Samitha Dewi Djajanti, Muhammad Bachri Amran, Muhammad Ali Zulfikar

Makara Journal of Science

A dummy-template molecularly imprinted polymer (DMIP) was synthesized via precipitation polymerization using anthrone as a template analog for the selective analysis of low-molecular-weight polycyclic aromatic hydrocarbons (PAHs), specifically fluorene and phenanthrene. Styrene, benzoyl peroxide, and ethylene glycol dimethacrylate were employed as the functional monomer, radical initiator, and crosslinking agent, respectively. The synthesized polymers were characterized by Fourier-transform infrared spectroscopy, scanning electron microscopy, and particle size analysis. The imprinting factors were 1.16 and 1.09 for fluorene and phenanthrene, respectively, indicating enhanced affinity of the imprinted sites. High-performance liquid chromatography analysis following DMIP-based solid-phase extraction yielded recoveries of 91.49% ± 3.87% for …