The use of short tandem repeats (STRs) for genotyping forensic case samples has long been an effective tool for human identification. However, interpretation of forensic STR mixture samples can be difficult and any additional information to aid in this process can be invaluable. Allele overlap and stutter during PCR can cause drop out of the minor contributor’s alleles and result in incorrect allele calling. The Scientific Working Group on DNA Analysis Methods (SWGDAM) provides a list of guidelines on how to interpret DNA typing results from forensic STRs and mixtures, but there is still a significant variation in the interpretation of mixture samples between analysts in the same laboratory and between laboratories. The Illumina MiSeq Forensic GenomicsTM system (Illumina Inc., San Diego, CA) is a massively parallel sequencing instrument that was developed specifically for the use in forensic DNA typing and which could provide sequence variations among on mixture samples. The ForenSeqTM DNA Signature Prep Kit is a kit that can be used with the MiSeq FGxTM platform. The DNA Primer Mix A (DPMA) included in the ForenSeqTM kit targets 27 autosomal STRs, 24 Y-STRs, 7 X-STRs and 94 identity single nucleotide polymorphisms (SNPs) on up to 32 or 96 samples, depending on the flow cell used. This study compares the STR performance on DNA mixtures of the MiSeq FGxTM and CE and evaluates its reliability and robustness. The MiSeq FGxTM provides data in read count and the CE in relative fluorescence units (RFU), so the two output data cannot be directly compared to one another. Instead, the ratio of two contributors was calculated at three mixture ratios (1:1, 1:4, and 1:9) to use as a mean of comparison. The mean contributor ratios calculated on the MiSeq FGxTM were 1.799, 7.595, and 13.524 for the 1:1, 1:4, and 1:9 mixtures, respectively. This was not significantly different from the CE mean contributor ratios of 1.818, 7.722, and 14.827, respectively. More allele dropouts occurred on the MiSeq FGxTM than the CE at both 1:4 and 1:9 mixture ratios, but sequencing provided the detection of six isoalleles based on sequence variants that could not be discerned by CE. Other studies have shown full profile generation at these ratios, indicating there could have been some issues during library preparation. Further studies should be performed to thoroughly validate the ForenSeqTM process and evaluate the sensitivity of the instrument. Until then, it is recommended that the ForenSeqTM kit and MiSeq FGxTM system be used at close to equal mixture ratios or in tandem with the CE to prevent genotypes miscalling.

Drugs of Abuse (DOAs) are among the single largest contributor to crime in the United States and present a high cost to society in terms of financial costs and physical/mental well-being of individuals. The forensic community requires a variety of validated methods to detect and analyze DOAs in a variety of different sample types, and most developed methods utilize a liquid or gas chromatography (GC or LC) separation system paired to a mass spectrometer (MS) detection detector. Capillary Electrophoresis (CE) based separation techniques have also been experimented with due to this technique’s high efficiency and speed, high resolving power, low sample consumption, and potentially lower cost when compared to GC or LC based techniques, even though the sensitivity of these systems is perceived to be weaker. The goal of this research to develop a CE-MS/MS method utilizing the ZipChipTM to demonstrate it can accurately and reliably detect and quantify DOAs. The DOAs analyzed for this method were opioids and benzodiazepines, and these were 6-monacetylmorphine, 7-aminoclonazepam, codeine, diazepam, dihydrocodeine, 2-Ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine fentanyl, heroin, hydrocodone, hydromorphone, meperidine, methadone, morphine, norfentanyl, oxycodone, and oxymorphone. Standard Practices for Method Validation in Forensic Toxicology guidelines from the Academy Standards Board (ASB) of Toxicology were used as the template for this validation; samples were prepared and analyzed as neat standards in diluent, blood and urine were assessed for interferences, ionization suppression/enhancement, and extraction recovery. The total runtime for the method was 3.5 minutes, with the retention time range being 1.4 to 2.9 minutes. All samples were prepared using compound standards diluted in metabolite diluent, which consisted of methanol, ammonium acetate, and water prior to injection. The calibration curves consisted of eight calibrator samples that ranged from 0.5 ng/ml to 200 ng/ml for all analytes, and a linear model was used for each compound. The minimum acceptable 𝑅2 value was set to >0.98, and each curve had a weighing factor of 1𝑥2. Each curve for most of the compounds achieved the minimum requirement apart from two Codeine curves (0.9781 and 0.9785) and 7-aminoclonazepam (0.9791). Bias and precision were assessed at three concentrations- 5, 100, and 150 ng/ml. The minimum requirement for bias and precision for a compound was if the percent bias or coefficient of variation was within +/- 20%. Most compounds in this method exhibit acceptable levels of bias (except for Dihydrocodeine which had a bias of 24.58% at 100 ng/ml), and the only compounds to meet the minimum requirement for precision were 6-MAM, 7-aminoclonazepam, diazepam, fentanyl, methadone, and morphine. The limit of detection and limit of quantitation were both set at the lowest calibrator level of 0.5 ng/ml, and no carryover was observed in this method. No interferences occurred due to both deuterated internal standards and from common compounds such as benzylecogine, cocaine, and lidocaine, but blood cause signal interference with fentanyl and urine caused signal interference with methadone and norfentanyl. Ionization suppression and enhancement was observed for a majority of the compounds, and this observation will need to be assessed as to the effect it has on validation parameters in the future. The results collected suggest that accurate, reliable, and sensitive data may be collected if a compound has a specifically paired deuterated internal standard included in the sample. The speed of the suggested method and the minimal sample preparation could be desirable for forensic use. Further testing will need to be conducted to fully validate this method for blood and urine.

The aim of this thesis was the development of the method for the determination of eight monosaccharides commonly found in glycoproteins by capillary electrophoresis. Namely, it was determination of glucose, galactose mannose, N-acetylglucosamine, N-acetylgalactosamine, fucose, N-acetylneuraminic acid and xylose. Total length of silica capillary with inner diameter of 10 m was 50.0 cm and effective length was 35.0 cm. Background electrolyte was compound of sodium hydroxide of 50 mmol/l concentration, disodium phosphate of 22.5 mmol/l concentration and cetyltrimethylamoniumbromide of 0.2 mmol/l concentration. Samples were injected hydrodynamically with pressure of 5 kPa for 70 s, driving voltage was -30 kV and the pressure of 270 kPa was applied to the outlet vial during the separation; capacitively coupled contactless conductivity detector was used to detect the analytes. The limits of detection were between 5 and 7 mg/l and the limits of quantification were between 16 and 22 mg/l. Repeatability of peak areas and migration times related to 4-(2-hydroxyethyl)-1-piperazinethanesulfonic acid as an internal standard showed values of relative standard deviation lower than 4 %. Conditions for hydrolysis of oligosaccharides to monosaccharides were determined as 4M hydrochloric acid and 100 řC, hydrolysis...

A sensitive method using capillary electrophoresis for the separation, detection, and quantification of dihydrokaempferol (1) is reported. Well-resolved, sharp symmetrical peaks were obtained in grapefruit leaf extracts for 1, naringenin (2), and the internal standard, naringin (3). Long columns were required to resolve 1 from 2 in crude enzyme reactions and this resulted in run times of 60 min. The limit of detection for 1 was found to be 1.44 ng/μL (4.2 pg). The method showed excellent linearity and reproducibility. The method was used to determine the activity of flavanone 3-hydroxytransferase (F3H) in leaf tissue of grapefruit by quantification of the production of dihydrokaempferol in controlled time course reactions. The sensitivity of the method makes it adaptable to assaying F3H activity in individual young seedlings and/ or in small tissue samples and requires only 100 mg of tissue.

The thesis introduces two developed methods to quantify extracellular vesicles (EVs) isolated from cancer cell lines and healthy human saliva by using capillary zone electrophoresis. In the first chapter, the importance of EVs, as well as the existing EV isolation, characterization, and quantification methods, are described. The general principle of capillary electrophoresis (CE) is explained for a better understanding of these two methods. Chapter II describes the idea and concepts of Extracellular Vesicles quantitative Capillary Electrophoresis (EVqCE). The method evolved from the previous study carried out in our research group for the quantification of viruses. After the isolation of EVs from different cell lines, the characterization and quantification of EVs were performed using nanoparticle tracking analysis (NTA) and flow cytometry. EVqCE consists of four steps for EV quantification. In this study, EVqCE was employed to know the concentrations of EVs in unknown samples, followed by calculation of the average mass of the RNA present in EVs. In the next chapter, one of the human body fluids, i.e., saliva, was chosen for the quantification of EVs. Salivary EVqCE was developed in a similar way as EVqCE for cell lines since the general theories and procedures are practically the same. However, human saliva contains an abundant amount of viscous proteins and ribonuclease (RNase), that were the major obstacles for salivary EVs detection and quantification. The method for the isolation of EVs from the saliva was optimized, and the quantification was performed successfully. The average mass of RNA in saliva EVs was also calculated and analyzed. The concentration of saliva EVs in unknown samples were compared with the results from NTA and flow cytometry to validate the salivary EVqCE. In the last chapter, I described the application of EVqCE to study the quality control of EVs. The method calculates the degradation level of EVs samples under different conditions, providing a potential way for real-time monitoring of the EVs status in the body fluid sample.

京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第21072号 / 工博第4436号 / 新制||工||1689(附属図書館) / 京都大学大学院工学研究科材料化学専攻 / (主査)教授 大塚 浩二, 教授 松原 誠二郎, 教授 秋吉 一成 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM

Capillary electrophoresis is a method used in pharmaceutical analysis because of its low cost, speed and environmental friendliness. This diploma thesis deals with development of electrophoretic method for rivaroxaban determination. After several optimizations, a method suitable for rivaroxaban determination inside its dosage forms was developed. Optimizations involved change of background electrolyte's composition from aqueous solution of low molecular weight organic acids to non-aqueous solution of acetic acid and cetyltrimethylammoniumbromide in acetonitrile in multiple steps. Final conditions of analysis included background electrolyte composed of 1M acetic acid and 40mM cetyltrimethylammoniumbromide in acetonitrile, sample injection carried out hydrodynamically by pressure of 5,0 kPa for period of 3 s and subsequent insertion of separation voltage of 30,0 kV for entire duration of analysis. Capillary content was mobilized by pressure of 0,50 kPa for entire duration of analysis. With aforementioned optimizations a selective method for determination of dosage forms of rivaroxaban was obtained. This method provides limit of detection 0,0056 mg/ml and limit of quantification 0,019 mg/ml and is linear in 0,01 - 0,40 mg/ml range with a recovery of 93,2 %. Keywords capillary electrophoresis,...

COVID-19 is caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). COVID 19 is detected by RT-PCR tests and serological tests. RT-PCR tests detect viral RNA and require trained individuals to run the test as well as a lengthy analysis time. Serological tests detect antibodies produced in response to viral infection. Rapid antigen detection (RAD) tests, such as the at-home COVID test kits, are quick and easy to run. RAD tests detect viral antigen in the test sample binding to the antibody-coated testing device. However, production of antibodies is a long and costly process. Aptamers can replace antibodies with advantages including low-cost, stability, tunable selectivity, and ability to be chemically modified. Aptamers are short single-stranded oligonucleotides selected for specific targets using Systematic Evolution of Ligands by Exponential Enrichment (SELEX). This project aims to characterize the binding of aptamers to SARS-CoV-2 nucleocapsid (N) protein using capillary electrophoresis (CE) and compare with bio-layer interferometry (BLI). DNA aptamers were selected via SELEX and screened using BLI in which protein was immobilized on the BLI sensor tip and dipped into aptamer solution. Three aptamers specific to N protein were selected for further binding affinity (Kd) determination. In CE, the aptamer and protein are free in solution to bind and unbind, providing an alternative approach in characterizing the binding. A greater Kd was observed with CE compared to BLI. Using CE, the apparent Kd of the 3 aptamers was determined to be 18 ± 4 nM, 45 ± 11 nM, and 32 ± 7 nM, respectively. When tested with BLI, the apparent Kd were 4.83 ± 0.63, 4.51 ± 0.87, and 2.91 ± 0.59 nM, respectively. This discrepancy in affinity can be due to steric differences between immobilized (BLI) and in solution (CE) binding, buffer composition and stability of aptamer structures, or buffer pH and difference in electrostatic interactions. All three of these variables will impact binding and the calculated Kd. This work offers insight into aptamer affinity when used in a different system from which they were selected. This work would lead to a better understanding when employing aptamers to different assays and assay mediums.

Interest in microchip capillary electrophoresis (CE) is growing due to the rapid analysis times provided and small sample input requirements. However, higher-concentration samples are typically needed because of the small (~pL) detection volumes in these devices. I have made membrane-based protein preconcentration systems in capillary and microchip designs to increase the detectability of low-concentration biological samples. A photopolymerized ion-permeable membrane interfaced with a microchannel in poly(methyl methacrylate) (PMMA) formed the preconcentrator. When a voltage was applied between the sample reservoir and the ionically conductive membrane in a capillary-based system, R-phycoerythrin was concentrated more than 1,000 fold, as determined by laser-induced fluorescence measurement. An integrated system that combines analyte preconcentration with microchip CE has also been developed using two different fabrication methods: polymerization and solvent bonding. In both approaches, microchannels within the PMMA substrates were interfaced with an ion-permeable hydrogel. When an electrical potential was applied along the channel, greater than 10,000-fold preconcentration was achieved for R-phycoerythrin. Concentrated protein samples were also injected and separated in these integrated microdevices. Membrane-based protein preconcentration devices can significantly increase the concentration range of biological samples that can be analyzed by microchip CE.

In this dissertation, several microfabricated devices are introduced to develop new applications in the area of chemical analysis. Electrochemical micropumps, chip-based liquid chromatography systems and multilayer capillary electrophoresis microdevices with crossover channels were fabricated using various substrates such as poly(dimethylsiloxane) (PDMS), glass, and poly(methyl methacrylate) (PMMA). I have demonstrated pressure-driven pumping of liquids in microfabricated channels using electrochemical actuation. PDMS-based micropumps were integrated easily with channel-containing PMMA substrates. Flow rates on the order of ~10 µL/min were achieved using low voltages (10 V). The potential of electrolysis-based pumping in microchannels was further evaluated for pressure driven microchip liquid chromatography (LC). Two micropumps were connected with reservoirs for sample and mobile phase, situated at the ends of microchannels for sample injection and separation, respectively. Columns micromachined in glass were coated covalently with an organic stationary phase to provide a separation medium. A pressure-balanced sample injection method was developed and allowed the injection of picoliter sample volumes into the separation channel. Fast (<40 s) separation of three fluorescently tagged amino acids was performed in a 2.5-cm-long microchip column with an efficiency of 3300 theoretical plates. Improved electrode designs that eliminate the stochastic formation of bubbles on the electrode surface will enhance pumping reproducibility. Multilayer polymeric microdevices having fluidically and electrically independent crossover channels were made using phase-changing sacrificial layers (PCSLs). High-performance electrophoretic separations of fluorescently labeled amino acids were carried out in multilayer PMMA microchips. Neither pressure nor voltage applied in a crossover channel resulted in negative effects on the separation quality in the main fluidic path. A fifty-fold reduction in crossover volumes was achieved in next-generation multilayered microchips. The ability to make minimal dead volume crossover channels facilitated the design and operation of multichannel array microdevices with a minimum number of electrical and fluidic inputs. Replicate electrophoretic separation of two peptides was performed in parallel for three independent microchannels connected to a single sample reservoir. My work demonstrates the value of PCSLs in making complex microfluidic structures that should expand the application of micro-total analysis systems.