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Background: Busulfan is widely used in conditioning regimens to prepare patients for hematopoietic stem cell transplantation. Therapeutic drug monitoring (TDM) is critical due to large inter- and intra-individual variability in busulfan pharmacokinetics, and the risk of adverse consequences of toxicity including hepatic veno-occlusive disease. Busulfan is most commonly measured by liquid chromatography–mass spectrometry (LC-MS/MS), which is not as widely available in clinical laboratories as automated routine clinical chemistry analyzers. The objective was to perform analytical verification of a busulfan immunoassay on the Abbott Alinity c platform. Methods: The MyCare Oncology busulfan immunoassay was configured as a third-party reagent on the Abbott Alinity c. Imprecision, linearity, sample carryover, and onboard stability of reagent studies were evaluated. The performance of the busulfan immunoassay using the Abbott Alinity c was compared to the Beckman Coulter AU480 using sodium heparinized plasma, as well as to LC-MS/MS using lithium heparinized plasma. Results: The imprecision goal of 8% was met, and linearity within the analytical measurement range of 240 to 1700 ng/mL was verified. Sample carryover was negligible, and the reagents were stable onboard for at least 84 days. The busulfan immunoassay correlated well with LC-MS/MS (slope = 0.949, y-intercept = −7.8 ng/mL, r2 = 0.9935) and the Beckman Coulter AU480 (slope = 1.090, y-intercept = −34.5 ng/mL, r2 = 0.9988). Conclusions: This study demonstrated successful analytical verification of a busulfan third-party immunoassay on the Abbott Alinity c platform. The ability to perform TDM of busulfan on a routine clinical chemistry analyzer will positively impact turnaround times to improve patient outcomes. [ABSTRACT FROM AUTHOR]

Guided by Honig and Hatch's conceptualization of bridging and buffering, we analyzed the first teacher collective bargaining agreements negotiated after the enactment of the Ohio Teacher Evaluation System to understand how state law has shaped provisions for teacher evaluation, compensation, reductions in force (RIF), transfers, and contract renewal. We found surprising variation in provisions across districts. Most notable was how districts defined comparable evaluations in making RIF decisions. Bridging districts provided the greatest protections for the most accomplished teachers, regardless of seniority. In contrast, buffering districts have RIF provisions based on seniority.

This paper investigates the ethics of regarding others as epistemically hopeless. To regard a person as epistemically hopeless with respect to p is, roughly, to regard her as unable to see the truth of p through rational means. Regarding a person as epistemically hopeless is a stance that has surprising and nuanced moral implications. It can be a sign of respect, and it can also be a way of giving up on someone. Whether it is morally problematic to take up this stance, I argue, depends on the choices that one faces (or is likely to face). I close the paper by arguing against the view that there are standing moral reasons against regarding others as epistemically hopeless. [ABSTRACT FROM AUTHOR]

This paper reports the design and ground-based testing of a multiplexed colorimetric solid-phase extraction (MCSPE) platform for the rapid determination of multiple water quality parameters in a simple set of operational steps. Colorimetric solid-phase extraction (C-SPE) is an analytical platform that combines impregnated colorimetric reagents on a solid-phase extraction membrane and diffuse reflectance spectroscopy to quantify trace analytes in water. In extending C-SPE to MC-SPE, a filter holder that incorporates discrete analysis channels and a jig that facilitates the concurrent operation of multiple syringes have been designed, enabling the simultaneous determination of three different measures of water quality. Separate, single-parameter membranes, placed in a readout cartridge create unique, parameter-specific addresses at the exit of each channel. Following sample exposure, the diffuse reflectance spectrum of each address is collected serially and the Kubelka-Munk function is used to quantify each water quality parameter via calibration curves. Performance evaluations of the MC-SPE platform were conducted using sample pH, silver(I), and nickel(II). Determinations of silver(I) (0.05-0.5 ppm) and nickel(II) (1.8-5.0 ppm) follow established C-SPE methods on reversed-phase extraction membranes using 5-(p-dimethylaminobenzylidene)rhodanine and dimethylglyoxime, respectively, as colorimetric reagents. Sample pH (2.5-5.0) is measured using an anion-exchange membrane impregnated with fluorescein. These determinations require ~120 s to complete using a total sample volume of 3.0 mL. The extension of MC-SPE to the determination of a greater number of analytes and its potential application to space and earth-bound monitoring needs are briefly discussed.

A new, rapid methodology for trace analysis using solid-phase extraction is described. The two-step methodology is based on the concentration of an analyte onto a membrane disk and on the determination by diffuse reflectance spectroscopy of the amount of analyte extracted on the disk surface. This method, which is adaptable to a wide range of analytes, has been used for monitoring ppm levels of iodine and iodide in spacecraft water. Iodine is used as a biocide in spacecraft water. For these determinations, a water sample is passed through a membrane disk by means of a 10-mL syringe that is attached to a disk holder assembly. The disk, which is a polystyrene--divinylbenzene composite, is impregnated with poly(vinylpyrrolidone) (PVP), which exhaustively concentrates iodine as a yellow iodine--PVP complex. The amount of concentrated iodine is then determined in only 2 s by using a hand-held diffuse reflectance spectrometer by comparing the result with a calibration curve based on the Kubelka--Munk function. The same general procedure can be used to determine iodide levels after its facile and exhaustive oxidation to iodine by peroxymonosulfate (i.e., Oxone reagent). For samples containing both analytes, a two-step procedure can be used in which the iodide concentration is calculated from the difference in iodine levels before and after treatment of the sample with peroxymonosulfate. With this methodology, iodine and iodide levels in the 0.1-5.0 ppm range can be determined with a total workup time of ~60 s with a RSD of ~6%.

Working at pH 2.4 with uncoated silica capillaries has the advantage that electroosmotic flow is virtually eliminated. Excellent separations of protonated organic bases were obtained when ethanesulfonic acid was added to the running electrolyte to coat the capillary surface by a dynamic equilibrium. The effect of adding a new surfactant, sulfonated Brij-30, to the acidic electrolyte was also investigated. Use of this surfactant in acidic organic - aqueous solutions changes the elution order of many organic cations and also permits the separation of neutral organic compounds. Excellent resolution of a mixture of 19 PAHs and similar compounds was obtained in 40% organic solvent in only 20 min. The largest organic compounds form the most stable association complexes with the sulfonated Brij-30 and, thus, have the shortest migration times. It is shown that the type and concentration of surfactant, as well as the composition of the aqueous-organic solution, are conditions that can be varied over a broad range to obtain superior separations of both neutral and cationic organic compounds. The type of organic solvent is yet another condition that can be manipulated advantageously. For example, the use of equal volumes of acetonitrile and 2-propanol in water - organic solutions can give better resolution of neutral organic analytes than either solvent used alone.

A nonionic surfactant (Brij-30) was treated with chlorosulfonic acid to form [C.sub.12][H.sub.25][(OC[H.sub.2]C[H.sub.2]).sup.4]OS[O.sub.3]-[Na.sup.+]. Addition of a low concentration of this material to an aqueous solution-acetonitrile electrolyte makes it possible to separate nonionic organic compounds by capillary electrophoresis. Separation is based on differences in the stabilities of analyte-additive complexes in solution. Migration times of analytes can be varied over an unusually large range by varying the additive concentration and the proportion of acetonitrile in the electrolyte. This greatly expands the scope of neutral organic compounds that can be separated by CE. Several examples are given. Some very difficult separations were achieved, such as the baseline resolution of four methylbenz[a]anthracene isomers and the separation of normal and deuterated acetophenone.

A low concentration of a surfactant added to a mobile phase containing 60% acetonitrile (+ 40% water) significantly reduces the capacity factors of organic analytes. An even greater reduction in k[prime] resulted from the use of binary additive systems, particularly those containing a cationic and an anionic surfactant. It is believed that an ion pair is formed that is more effective in forming solution complexes with organic analytes than either additive alone. Other binary additive systems included mixtures of a neutral and a charged additive or a mixture of two anionic surfactant additives. A ternary mixture of additives was more effective than any of the binary mixtures in modifying the chromatographic behavior of organic solutes in HPLC.

Excellent separations of nonionic organic compounds were obtained by adding sodium dioctyl sulfosuccinate (DOSS) to an acetonitrile ([approximately] 40% v/v)-water electrolyte. Separation is based on differences in the strength of analyte-DOSS association 'complexes' in solution, which results in differences in effective electrophoretic mobility. Micelle formation is not believed to occur. The effects of varying apparent pH, applied voltage, acetonitrile concentration, and DOSS concentration were studied with regard to electroosmotic mobility and effective electrophoretic mobility. Under optimum conditions, excellent separations of 23 organic compounds were obtained.