158 research outputs found
Molecular flexibility of polymethylene molecules: a Raman spectroscopic study
No full textThe Raman spectrum in the CH stretching region of molecules containing long alkyl residues
shows characteristic features which provide direct information on their molecular flexibility, as
probed by the C-H stretching oscillator which vibrates on the picosecond time scale. From
their Raman spectra, librational motions of the (CH2 )n units can be studied for molecules in
the solid and liquid phases. In the latter case, segmental motions must be considered. In this
paper, the spectra of hydrocarbons in the solid, liquid and as clathrates in urea and
perhydrotriphenylene are studied in terms of their overall mobility. Using molecular
dynamical calculations we show the existence of a selective coupling between CH stretchings
and skeletal torsions, which is modulated by the collective mobility of the carbon skeleton. In
particular, we account for the frequency dependence of the antisymmetic CH stretching mode
using a model which allows for selective coupling between this high frequency mode and the
low frequency torsional oscillations about the C-C bonds in the chain
OPTIMIZATION AND APPLICATION OF PHOTOLUMINESCENCE- FOLLOWING ELECTRON-TRANSFER WITH TRIS(TETRAMETHYL- 1,10-PHENANTHROLINE) Os/Ru(III) COMPLEXES AND FENTON BASED CHEMILUMINESCENCE DETECTION OF NSAIDS AND DOPAMINE IN BIOLOGICAL SAMPLES
No full textBiogenic monoamines such as dopamine play an important role as major neurotransmitters. Simultaneous determination of the concentration changes is thus crucial to understand brain function. Additionally, quantification of pharmaceutically active compounds (PhACs) and their metabolites in biological fluids is an important issue for forensic tests, clinical toxicology and pharmaceutical analysis. We have developed two postcolumn luminescence detection methods coupled to a 2-dimensional-solid phase extraction (2D-SPE) system. The postcolumn reaction methods used in this study are the redox-dependent photoluminescence-following electron-transfer (PFET) and Fenton-based chemiluminescence techniques, for the determination of certain neurotransmitter and nonsteroidal anti-inflammatory drugs (NSAIDs). A stable [Os(tmphen)3]3+ (tmphen = 3,4,7,8-tetramethyl-1,10-phenanthroline) reagent was prepared in neutral aqueous solution by oxidation of [Os(tmphen)3]2+ with lead(IV) oxide. [Os(tmphen)3]2+ and [Os(tmphen)3]3+ are characterized by absorption spectroscopy. [Os(tmphen)3]3+ stability is compared with [Ru(tmphen)3]3+ in the same pH 7 environment. The properties of Os(III) and Ru(III) complexes were investigated for use as the oxidant in a PFET system. Studies of photophysical and electrochemical properties, the stability of the Os(III) and Ru(III) complexes, and analytical application in PFET detection of oxidizable analytes are presented. The spectroscopic properties of the complexes were not very advantageous, but careful control of the detection system and reaction conditions enabled sensitive detection of the analytes. The method was fully validated and the optimized system was capable of detecting dopamine and acetaminophen at about 30.2 µg L-1 and 33.5 µg L-1, respectively. The limit of detection (LOD) was 1.5 µg L-1 for acetaminophen and 4.3 µg L-1 for dopamine. The accuracy and precision were within bioanalytical method validation limits (90.9 to 101.5 % and RSD < 12.0 %, respectively). Typical analysis time was less than 15 minutes. Two Fenton-based flow-injection chemiluminescence (CL) methods were developed and validated for the determination of naproxen. Under the optimal experimental conditions the proposed methods exhibited advantages in a larger linear range from 2,760 ng mL-1 to 207,000 ng mL-1 for the first CL method and 41.4 ng mL-1 to 700.0 ng mL-1 for the second CL method. The LOD was 13.8 ng mL-1 for naproxen. The CL mechanisms for the system, H2O2-FeIIEDTA-naproxen was further studied by batch experiments, chemiluminescence spectroscopy, fluorometry, high pressure liquid chromatography (HPLC) and Fourier transform infrared spectroscopy (FTIR). The effects of various interferences commonly found in biological and wastewater systems on the chemiluminescence intensity were also investigated. We used these methods to determine NSAIDs in commercial pharmaceutical formulations. Another application of these method was for detecting NSAIDs in biological samples. A 2x-1-Dimensional Solid Phase Extraction (2x-1D SPE) method was developed for determination of acetaminophen and naproxen in urine. This method uses both the methanol concentration and the pH advantageously to preferentially isolate analytes of interest from complex sample matrix. These methods were fully validated and had sufficient sensitivity (limit of quantification: acetaminophen; 40.41 mg L-1 - 360.0 mg L-1 and naproxen; 23.03 mg L-1 - 214.8 mg L-1) for biological matrices and applications.Chemistr
THE EVALUATION OF LARCH ARABINOGALACTAN AS A NEW CARRIER IN THE FORMULATION OF SOLID DISPERSIONS OF POORLY WATER- SOLUBLE DRUGS
No full textAdvanced drug discovery techniques have produced more lipophilic compounds. Formation of an amorphous solid dispersion of such poorly water-soluble drugs improves their solubility and dissolution. This results in greater in vivo bioavailability. Thus, it is one of the recent trends in the development of oral dosage forms. In solid dispersions, the carrier is crucial for ensuring the functionality and stability of these systems. Larch arabinogalactan FiberAid grade (AGF) is generally recognized as safe (GRAS) designated, amorphous polymer. The objective of this dissertation project was to perform a comprehensive evaluation of AGF as a carrier for amorphous solid dispersions. First, a detailed characterization of the AGF polymer was performed. A special focus on its use as a solid dispersion carrier was emphasized. The glass transition temperature and the degradation temperature of the AGF polymer were ~82 oC and ~185 oC, respectively. The AGF polymer had good hygroscopicity. Ibuprofen-AGF solid dispersions were evaluated for dissolution enhancement. Ibuprofen-Hydroxypropyl methylcellulose grade K3 (HPMCK3) solid dispersions were investigated simultaneously as a control polymer dispersion. The ibuprofen-AGF solid dispersions were amorphous at nearly 20% ibuprofen load. The dissolution of the ibuprofen from AGF solid dispersions was significantly greater than that of the neat ibuprofen. The formation of the amorphous state of ibuprofen and solution-state ibuprofen-AGF interactions were the mechanisms of the ibuprofen dissolution enhancement. At a 10% ibuprofen load, the dissolution of the AGF solid dispersion was found greater than that of the dissolution of the HPMCK3 solid dispersion. Secondly, the itraconazole-AGF solid dispersions and the ketoprofen-AGF solid dispersions were characterized and compared them with the ibuprofen-AGF solid dispersions. The comparisons were established for the miscibility and dissolution enhancement. The order of increase in dissolution was ketoprofen-AGF solid dispersions > itraconazole-AGF solid dispersions> ibuprofen-AGF solid dispersions. The same order was observed for the solid-state miscibility of these drug-AGF solid dispersions. Additionally, the solid dispersions of 9 drugs with the AGF polymer were investigated to elucidate the detailed mechanism of drug crystallization inhibition by the AGF polymer. The inherent tendency of the AGF polymer to inhibit the drug crystallization, drug-AGF solid-state hydrogen bonding and the anti-plasticizing effect of AGF were the mechanisms underlying the crystallization inhibition by the AGF polymer. Last, a storage stability of ibuprofen-AGF amorphous solid dispersions after storage under accelerated conditions (for 3 months) and ambient conditions (for 6 months) was investigated. The amorphous ibuprofen from AGF solid dispersions was physically and chemically stable under stability conditions. In summary, the AGF polymer was evaluated as a novel carrier for formation of an amorphous solid dispersions. The studies established that the AGF polymer was comparable to HPMCK3 polymer. The AGF polymer could be more advantageous than the HPMC polymer for the preparation of solid dispersion when faster dissolution is desired at lower drug load.Pharmaceutical Science
Development of Polyphenolic Nanoparticles for Biomedical Applications
No full textPolymeric nanoparticles have a wide range of applications, particularly as drug delivery and diagnostic agents, and tannins have been regarded as a promising building block for redox and pH responsive systems. Tannins are a class of naturally occurring polyphenols commonly produced by plants and are found in many of our consumables like teas, spices, fresh fruits, and vegetables. Many of the health benefits associated with these foods are a result of their high tannin contents and the many different types of tannins found in various plants have demonstrated therapeutic potentials for conditions ranging from cardiovascular disease and diabetes to ulcers and cancer. Diets rich in tannins have been associated with lower blood pressure in patients with hypertension. The plurality of phenols in tannins also makes them powerful antioxidants and as a result, there is a lot of interest in taking advantage of their self-assembling abilities to make redox and pH responsive drug delivery systems. However, the benefit of natural tannins is limited by their instability in physiological conditions. Furthermore, there is limited control over molecular weight and reactivity of the phenolic content of plant extracts. Herein we report the novel synthesis of pseudotannins with control over molecular weight and reactivity of phenolic moieties. These pseudotannins have can form nanoscale interpolymer complexes under physiological conditions and have demonstrated antioxidative potential. Furthermore, pseudotannin IPCs have been shown to be responsive to physiologically relevant oxidation as well as the ability to easily incorporate cell targeting peptides, fluorescent tags, and MRI contrast agents. The work presented here describes how pseudotannins would be ideally suited to minimally invasive techniques for diagnosing atherosclerotic plaques and targeting triple negative breast cancer. We demonstrate that pseudotannin can very easily and quickly form nanoscale particles that are small enough to be uptaken into mammalian cells. Furthermore, by self-assembling with gadolinium, pseudotannins can effectively attenuate the signal of gadolinium based MRI contrast agents. This in conjunction with oxidation responsive decomplexation could be a viable option for diagnosing the severity and risk of rupture of atherosclerotic plaques. Also, we demonstrate that pegylated compounds can easily be incorporated into pseudotannin nanoparticles to impart cell targeting functionality. The subsequent uptake of pseudotannin nanoparticles into breast cancer cells demonstrated the ability to increase their sensitivity to UV radiation. The creation of synthetic tannin-like polymers leads to directly to making a variety of self-assembling, stimuli responsive, and bioactive nanoparticles well-suited for various biomedical applications.Bioengineerin
SYNTHESIS AND FUNCTIONALIZATION OF 1,4-POLYKETONES AND ENANTIOSELECTIVE POLYESTER CATALYST DEVELOPMENT USING MOLECULAR LEGO SCAFFOLDS
No full textObjectives of the present study are aimed towards improving upon alternating copolymerization techniques for polyketones and aliphatic polyesters, and the majority of this work is focuses on post-polymerization modifications to alternating polyketones. These materials are currently under studied in the literature, but the aptly spaced, repeating carbonyl functionality creates an easily functionalized material. Complimentary work described herein relates to efforts currently underway to prepare highly enantioselective catalysts for the alternating copolymerization of epoxides with cyclic anhydrides. Aliphatic polyesters currently suffer from a lack of chemical diversity, and, with greener chemistries on the forefront of research efforts, polyesters made from environmentally benign and/or renewable materials are desirable. Additional limitations of aliphatic polyesters include difficulty obtaining stereoregular polyesters. In collaboration with the Schafmeister laboratory we are developing catalysts for the alternating copolymerization of polyesters to address these limitations. The model catalysts are carefully designed scaffolds of spiroligomers encasing a Lewis acidic transition metal at its center ([spiro]MX). The spiroligomer bulk around the metal center imparts significant chirality onto the catalyst thereby controlling which enantiomer of a given monomer is polymerized leading to stereoregular polyesters. Additionally, the use of more than one monomer increases the available chemical space with which to create novel polyesters. To date, three [spiro]MX catalysts have been prepared all of which are catalytically active for poly(propylene maleate) synthesis. A core objective of this work is the study of functionalization methods to create novel materials from an inexpensive polyketones. The chemical modifications performed on polyketones to date have been limited, and the utility of the functionalized materials often goes unmentioned. Efforts to functionalize polyketones in this study were aimed at creating electrically conducting polymeric materials which would be used as hole transport materials in photovoltaic devices. Polyketones were decorated with pendant (tri)arylamine functionality creating several novel polymeric materials, and electrochemical experiments supported the formation of radical cations at the triarylamine nitrogen of the pendants. Further, the functionalization of the polyketones provided enhanced ultraviolet stability of the functionalized polymers. Concurrent to the functionalization of polyketones, we investigated the effects Lewis acids had on the synthesis of the polyketone itself. Through previous research conducted in the Dobereiner laboratory we know that a Lewis acid will interact with carbonyls of molecules during catalytic reactions. The addition of Lewis acids to the synthesis of the polyketones is thought to have similar interactions altering the polymerization. This study explored the bulk properties of the polyketone synthesized in the presence of several Lewis acids. As a result of this study specific polymer properties (e.g. molecular weight) could be targeted through careful selection of the Lewis acid and the amount added during polymerization.Chemistr
HIGH RESOLUTION INFRARED - INFRARED DOUBLE RESONANCE SPECTROSCOPY STUDY OF THE TRIPLET GROUND STATE OF THE RUBIDIUM DIMER
No full textThis thesis consists of two parts. The first part is focused on the high resolution infrared-infrared (IRIR) double resonance spectroscopy study of the Rubidium dimer triplet ground state a3Σu+. We have observed fluorescence to this state for J=30, 50 and 70 rotational quantum numbers. We have used a perturbed pair of rovibrational levels in the A1Σu+ ~ b3Πu electronic states as an intermediate excitation step to the higher lying 23Πg state to get access by fluorescence decay to the a3Σu+ state. This allowed us to calculate the term values and the potential energy curve for the triplet ground state. The second part of the thesis is a computational study of lifetimes and transition dipole moment matrix elements for the sodium dimer ion pair states of 1Σg+ symmetry. These calculated parameters will be helpful for the design of a quadruple resonance based Autler-Townes spectroscopic probe of the transition dipole moments between these states and the A1Σu+ state. The calculated lifetime values compare well with results from literature when available. This work was supported by the National Science Foundation through awards PHY 0245311, PHY 0555608 and PHY 0855502.Physic
USING ANALYTICAL METHODOLOGIES TO ASSESS THE ORGANOLEPTIC CHARACTER OF CITRUS ESSENTIAL OIL
No full textEssential oils are natural products used to flavor food and beverages. With the increase in nutrition conscious consumers, manufacturers of food additives and food products are faced with the challenge of making healthy alternatives. In particular, food products going to market with label claims stating reductions in sugar and salt, organic certified, organic compliant, and all natural; moreover the ingredients used in flavors must meet these label claims as well. More often than not, the challenge in using ingredients that follow these requirements is the pricing, the sourcing and the variability among those sources. Variability is common in the ingredients coming from nature such as fruits and plants because the area of cultivation can vary by the soil at the sight of planting and/or the climate in the region. Pricing is also problematic in naturally grown ingredients because it is a matter of supply and demand. Stock could be depleted from natural disasters, disease carrying pest(s), pests that consume the crop, and/or other causes for scarce supply of crop(s). Essential oils are natural byproducts of fruit, peels, and leaves from plants that contribute to flavor formulae for a large variety of food products. Because the essential oils are a crop based commodity, every variety has inherent differences based on the growing conditions and their ripening stages [1]. Nevertheless, each type of oil has marker chemicals that make up the majority of its composition; these marker chemicals have the tendency to degrade over time based on their interaction with light, oxygen exposure, and temperature. For companies that manufacture flavorings, understanding the variability among sources of essential oils as well as the possible degradants of essential oils is valuable information to obtain because it is possible the variants and degradants will negatively impact the flavor profile. Flavor is without question the most important attribute of the food we consume and by default stability of said flavor(s) need to be understood [30]. The content in this dissertation involves the stability analysis of a common essential oil, Oil Mandarin Italian Select, from Citrus Reticulata Blanco. It has known off notes that form from unknown causes. Most common is the plastic note that has formed in carbonated products like soda. Studying this particular essential oil in various conditions is intended to shed light on what those degradants are and under which conditions they form to give mandarin oil an off-note when applied to high acid and carbonated beverage applications. Once the note is reproduced, a correlation between analytical data and sensory interpretation of the oil will be developed. Mandarin essential oil being in the Citrus genus is traditionally analyzed via gas chromatography (GC) because of the high quantities of volatile constituents that give an oil high aroma activity. The volatile fraction of mandarin oil to be studied includes stability of methyl-N-methylanthranilate (MNMA), a major component giving mandarin its distinct grapey character, as well as gamma terpinene, thymol, sinensal, alpha pinene, beta pinene, myrcene, para cymene, alpha terpineol, and beta caryophyllene. Each of these ten compounds contributes to the unique flavor profile of mandarin oils when compared to orange and tangerine essential oils [1]. It was the common knowledge that para cymene can be perceived as rancid in aroma and the many interconversions the terpenes make that cause para cymene formation in Citrus oils, which made monitoring the changes of this chemical in the three stability environments crucial. Attention is being paid to para-cymene, as a specific marker of degradation in Citrus. The data obtained from the applied stability studies were challenging to understand as the marker chemicals are volatile and sensitive to chemical change. In this work the chemical changes and trends were analyzed under various storage conditions. Significant statistical analyses were employed to help define criteria of usability. The analyses were required because of natural variants and apparent inconsistencies of the data. Dixon Q Test and the Z Test were applied to determine outliers. Additionally, the Bland Altman method was applied to compare storage conditions and to determine if this statistical approach could be used to define significant changes in the marker chemical stability. The Bland Altman plots suggest that each component met the statistical limits of agreement, meaning the samplings were not significantly changing, statistically speaking. A final approach to assess the analytical data of the mandarin oil for significant change was the mass balance of each marker chemical from week 0 to week 24. Instrumental fluctuations have an acceptable range of +/- 20% in the industry; hence, a significant change criterion for a chemical in the mass balance must be one that exceeded +/- 20%. Unlike classical statistic methods, the mass balance was indicative that significant change had occurred to the compounds in the three studies. Upon sensory analysis of the oil samples, display of plastic note, oxidation, and overall loss of characteristic mandarin notes, the mass balance was found to correlate best to the significant change detected by sensory evaluation of the oil samplings. Due to the inadequate number of validated methods on Citrus essential oil research and the absence of large groupings of terpenes validated in a unified methodology, reconciliation of mass balance is an underutilized method of assessment in the literature. As a final assessment of the GC method validated, a product containing the selected mandarin oil was analyzed to evaluate the ability of the method to separate the oil components within a significantly more complicated matrix than the initial samples. The method was successful though not all marker chemicals were detected due to their low formulation concentration being below the level of detection of the method. This should not be seen as a failure of the method. For the major components of the essential oil studied, the method was quantitatively successful, meeting industry requirements.Chemistr
METABOLITE PROFILING OF SYNTHETIC CANNABINOIDS AND IDENTIFICATION IN HUMAN BLOOD VIA HUMAN LIVER MICROSOME INCUBATION AND HIGH RESOLUTION TANDEM MASS SPECTROMETRY
No full textSynthetic cannabinoids are recreational drugs designed to mimic the effects of Δ9-tetrahydrocannabinol (THC), the main psychoactive component present in cannabis. These drugs exhibit severe toxic effects upon consumption due to their high binding affinity and potency at the cannabinoid receptors (CB1 and CB2). Synthetic cannabinoids have proliferated over the last decade and become a major public health and analytical challenge, critically impacting the clinical and forensic communities. Indazole carboxamide and indole carboxamide class synthetic cannabinoids have been particularly rampant, and are the compound classes most frequently reported to governmental agencies worldwide. However, the metabolic and pharmacological properties of many of these compounds remains unknown. Elucidating these characteristics allows members of the clinical and forensic communities to identify causative agents in patient samples, as well as render conclusions regarding their toxic effects. The aim of this research study was to assess the in vitro Phase I metabolic profile of five synthetic cannabinoids and report the major metabolites identified; compounds evaluated included MDMB-CHNINACA; APP-CHMINACA (PX-3); 5F-APP-PICA (PX-1); 5F-MDMB-PINACA (5F-ADB); and FUB-AMB. These analytes were incubated for 120 minutes with human liver microsomes, followed by analysis of the extracts via ultra high performance liquid chromatography – tandem mass spectrometry (UHPLC-MS/MS). The high-resolution mass spectrometry tool utilized (quadrupole-time of flight mass spectrometry, QTOF) allowed for a thorough characterization of the metabolites, including the assignment of a chemical formula and structure, and accurate mass. The metabolic stability and kinetic profiles of 5F-ADB and FUB-AMB were evaluated by aliquoting the incubation samples at various time points throughout the procedure. It was observed that these compounds were metabolized rapidly, resulting in short half-lives and relatively elevated metabolic clearances. A variety of metabolites were identified for most of the species studied, and this was dependent on the chemical structure of the parent molecule. The major metabolites identified overall for the species were products of amide or ester hydrolysis; hydroxylation (including polyhydroxylation) of the pentyl side chain or cyclohexylmethyl moiety; and oxidative defluorination. It is proposed that these metabolites (especially analyte-specific metabolite) be included in laboratory assay panels to facilitate unequivocal identification of the synthetic cannabinoid agent of interest. For select compounds (5F-ADB and FUB-AMB), authentic forensic human blood samples which screened positive for these analytes were provided by a renowned forensic toxicology laboratory. These samples were tested to verify that the major metabolites identified in the in vitro studies were also present in blood in vivo; the resultant data from the 5F-ADB and FUB-AMB samples showed that the major hydroxylated and hydrolysis metabolite, respectively, were present in greater abundance than the parent molecule, which was most often absent or not present in an appreciable quantity. Additionally, it was observed in the time studies of 5F-ADB and FUB-AMB that the metabolites containing carboxylic acid functional groups were detected in incubation samples longer than the hydroxylated metabolites, potentially indicative of longer detection windows in human samples. These findings have important toxicological implications; many synthetic cannabinoid metabolites, including those identified in this study may have pharmacological activity and contribute to a drug user’s overall impairment profile; identifying them in blood in the absence of parent compound can point to the causative agent. The results demonstrate that it is imperative that synthetic cannabinoid assays screen for known pharmacologically active metabolites; this is particularly important for drugs with short half-lives. The results of this research can be applied to the prediction of metabolic pathways for synthetic cannabinoids as well as non-drug substances with similar structural elements whose metabolic profile has not yet been elucidated, and whose pharmacological activity is currently unknown. Additionally, the results provide reference standard manufacturers and research scientists with further insight into the metabolic products of synthetic cannabinoids and related compounds for the synthesis of materials for the development of laboratory assays.Chemistr
DEVELOPMENT OF HPLC METHODS FOR PHARMACEUTICALLY RELEVANT MOLECULES; METHOD TRANSFER TO UPLC: COMPARING METHODS STATISTICALLY FOR EQUIVALENCE
No full textHigh Pressure Liquid Chromatography (HPLC) is a well-known and widely used analytical technique which is prevalent throughout the pharmaceutical industry as a research tool. Despite its prominence HPLC possesses some disadvantages, most notably slow analysis time and large consumption of organic solvents. Ultra Pressure Liquid Chromatography (UPLC) is a relatively new technique which offers the same separation capabilities of HPLC with the added benefits of reduced run time and lower solvent consumption. One of the key developments which facilitate the new UPLC technology is sub 2-µm particles used as column packing material. These particles allow for higher operating pressures and increased flow rates while still providing strong separation. Although UPLC technology has been available since early 2000, few laboratories have embraced the new technology as an alternative to HPLC. Besides the resistance to investing in new capital, another major roadblock is converting existing HPLC methodology to UPLC without disruption. This research provides a framework for converting existing HPLC methods to UPLC. An existing HPLC method for analysis of Galantamine hydrobromide was converted to UPLC and validated according to ICH guidelines. A series of statistical evaluations on the validation data were performed to prove the equivalency between the original HPLC and the new UPLC method. This research presents this novel statistical strategy which can be applied to any two methodologies to determine parity.Chemistr
Novel Adiponitrile-Based Cocrystalline Solid State Electrolytes for Lithium-Ion Batteries
No full textThe demand for improved energy storage has and will continue to exponentially increase as technology advances. Electric vehicles, cell phones and laptops predominantly use lithium-ion batteries (LIBs) due to their inherent high energy densities and their ability to be recharged. However, issues such as charging rates, flammability concerns, energy density need to be addressed in the advancement and innovation of LIBs. Current LIBs suffer from acute safety issues due to the use of a volatile liquid electrolyte. These issues occur when lithium metal gets deposited irregularly onto the surface of electrodes during charge/discharge cycling, forming lithium dendrites. The dendrites then form an electronically conductive path between the cathode and the anode, causing thermal runaway. To remedy this dangerous safety issue, solid state batteries have been explored. A solid-state battery (SSB) removes the volatile liquid electrolyte and replaces it with a solid, ionically conductive electrolyte. Historically, many types of solid-state batteries have been researched, all with some critical flaw(s) that prevent them from widespread commercial adoption. Ceramic types such as Lithium lanthanum zirconium oxide (LLZO) have high ionic conductivity (>10-3 S cm-1), but suffer from mechanical brittleness, creating excess interfacial failure modes. However, polymer types such as polyethylene oxide (PEO), tend to have better interfacial contact, though they suffer from poor ionic conductivity. Improving mechanical and chemical interfacial contact between the solid-state electrolyte and electrodes, while maintaining high ionic conductivity, will provide a major improvement to the success of solid-state battery adoption. The work presented in this thesis explores novel soft solid cocrystalline electrolytes as an avenue for improved interfacial electrolyte-electrode contact while maintaining high ionic conductivity. By exploiting hard soft acid base theory, novel dinitrile-based cocrystals containing low-cost starting materials were synthesized and characterized as solid-state electrolytes. The utilization of LiBF4, adiponitrile (ADN) and/or succinonitrile (SCN) in thesecocrystals decreases Li-Li distances compared to previously reported cocrystals, thereby promoting the migration of Li-ions. Select cocrystal also reached ionic conductivity values of > 10-4 S cm-1, nearly matching that of ceramic electrolytes. Novel single-crystal-to-single-crystal (SCSC) phase transition were characterized in both LiBF4 and adiponitrile/LiBF4 cocrystals. The synthesis, thermal, and electrochemical characterization techniques for these compounds include both single crystal and powder x-ray diffraction, thermogravimetric analysis, differential scanning calorimetry, and electrochemical impedance spectroscopy.Chemistr
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