Publications by authors named "William M Kolling"

Olmesartan medoxomil (OLM) is only available in the United States as tablets. The United States Pharmacopoeia (USP) has placed OLM on its priority list of preparations that require stability data to support practitioner compounding. The purpose of the study was to develop a stability-indicating assay and then determine the beyond-use date (BUD) for an extemporaneous OLM suspension.

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Thioguanine (TG) is available only in the form of 40 mg tablets in the United States, and the patient population in which TG is used comprises mostly children. Recognizing its importance as a therapeutic agent and limited stability data for its compounded preparation, the United States Pharmacopoeia has listed TG in its priority list of compounded preparations monographs. The goal of the present study was to generate stability data and establish a beyond-use date for compounded TG suspension.

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Tetracaine is a potent ester-type local anesthetic. Recent publications describe the use of TC free base in topical anesthetic formulations containing propylene glycol. While solvolysis of tetracaine in propylene glycol solutions has been reported, there are no detailed reports on the kinetics of tetracaine reaction with propylene glycol.

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Tetracaine topical solution may improve patient adherence with topical clotrimazole therapy for fungal otitis externa. The chemical stability of tetracaine 1% and combination clotrimazole 1% with tetracaine 1% topical solutions was determined using a stability-indicating high-performance liquid chromatography assay. Propylene glycol and polyethylene glycol 400 were used as anhydrous solvents.

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For most medically amenable conditions, adherence to drug therapy is a necessary condition for a successful outcome. Drug side effects, especially pain, can interfere with the desired outcome. We report a case of non-adherence due to severe pain associated with the topical use of clotrimazole 1% solution in the ear.

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OBJECTIVE. To assess the effectiveness of using a vapor pressure osmometer to measure the accuracy of pharmacy students' compounding skills. DESIGN.

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The goal of this research work was to develop a novel technique to synthesize calcium alginate nanoparticles using pharmaceutically relevant microemulsions. Stable microemulsion-based reactors were prepared using aqueous sodium alginate, aqueous calcium chloride, dioctyl sodium sulfosuccinate (DOSS), and isopropyl myristate. The reactor microemulsions were characterized via conductivity and dynamic light scattering (DLS) experiments.

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The purpose of this study was to isolate starch from the tubers of Cyperus esculentus L. and evaluate its physicochemical and binder properties. Extraction of starch using sodium metabisulfite yielded 37 g of starch per 100 g of the tubers.

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Purpose: The stability of sodium bicarbonate solutions in sterile water for injection or 5% dextrose injection stored at 21-24 degrees C or 2-4 degrees C was evaluated.

Methods: Sodium bicarbonate injection was obtained in 50-mL vials of 8.4% (1 meq/mL).

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Poly(ethylene oxide) (PEO) was used to prepare thin polymer films containing clotrimazole (CT) utilizing hot-melt extrusion (HME) technology. Films containing PEOs of two different molecular weights and the drug were investigated for solid-state characteristics, moisture-sorption, bioadhesivity, mechanical properties, release characteristics, and physical and chemical stability of the drug within the HME films. The solid-state characterization of the drug and the polymer were performed utilizing differential scanning calorimetry and X-ray diffractometry.

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The first goal of this work was the preparation of a water-in-oil microemulsion from components generally regarded as safe for use in humans. Stable formulations without need of a co-surfactant were prepared from isopropyl myristate (IPM), dioctyl sodium sulfosuccinate (DOSS), and water. A ternary phase diagram was prepared for the IPM/DOSS/water system.

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The adsorption of amitraz to various adsorbents was studied in terms of the amount and rate of adsorption and the effect that adsorption had on the stability of amitraz in an aqueous environment. Adsorption results showed that in terms of their ability to adsorb amitraz from solution the adsorbents tested in this study can be ordered as follows: coarse carbon > cation exchange resin > or = anion exchange resin > fine carbon. Amitraz was not adsorbed on sand and potassium oxihumate.

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This paper reports the identification and preparation of three crystalline (A-C) and one metastable form (D) of amitraz. These were identified by their crystal morphology, crystal structures, aqueous solubility, and thermal properties. Form C was the least soluble (7 mug/mL) and had the highest melting point (115 degrees C).

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Hot-melt extrusion technology was used to prepare thin polymer films containing hydroxypropyl cellulose and clotrimazole (CT). Films containing hydroxypropyl celluloses of different molecular weight and the drug were investigated for moisture-sorption, mechanical properties, and release characteristics. Stability of the films was also studied at 25 degrees C/60% relative humidity (RH) and 40 degrees C/75% RH for up to 3 months.

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The purpose of this research was to investigate the interaction of water with ethylcellulose samples and assess the effect of particle size on the interaction. The distribution of water within coarse particle ethylcellulose (CPEC; average particle size 310 micro m) and fine particle ethylcellulose (FPEC; average particle size 9.7 micro m) of 7 cps viscosity grade was assessed by differential scanning calorimetry (DSC) and dynamic vapor sorption analysis.

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The purpose of this study was to elucidate the formation of crystal hydrates of niclosamide and to delineate the effect of relative humidity on the crystal forms obtained from acetone and ethyl acetate. Recrystallization of niclosamide was performed in the presence and absence of moisture. Two hydrates and their corresponding anhydrates were isolated.

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The objective of the study was to assess and compare the interaction and distribution of water within microcrystalline cellulose (MCC) and chitosan by differential scanning calorimetry (DSC) and dynamic vapor sorption analysis. The amounts of nonfreezing and freezing water in hydrated samples were determined from melting endotherms obtained by DSC. After accounting for the percent crystallinity of MCC and chitosan, no statistically significant difference was observed in their ability to bind water molecules per repeating unit at the minimum water content at which freezing water is evident.

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