1N Sodium Hydroxide Research Articles

The treatment of alkaline burns of the skin by neutralization.

Literature reports dating as far back as 1927 have lured clinicians into the belief that alkaline skin burns are best treated by water dilution and that neutralization attempts should be avoided. Although this belief has never been substantiated, neutralization of an alkaline burn of the skin with acid was thought to increase tissue damage secondary to the exothermic nature of acid-base reactions. The authors proposed that topical treatment of alkaline burns with a weak acid such as 5% acetic acid (i.e., household vinegar) would result in rapid tissue neutralization and reduction of injury in comparison to water irrigation alone. In a rat skin burn model, animals were exposed to an alkaline injury when filter paper (2 cm in diameter) saturated with 2N sodium hydroxide was placed over the volar aspect of the animal for a period of 1 minute. Treatment was initiated 1 minute after injury and included either neutralization with a 5% acetic acid solution (n = 8) or irrigation (n = 8) with water. Skin temperature and pH were monitored using subdermal needle probes until the pH of the skin returned to physiologic values. Punch-biopsy specimens were obtained from the wound edges 24 hours after injury to assess burn depth and leukocyte infiltration, and biopsies were repeated 10 days later to assess wound healing. The authors proposed that neutralization of an alkaline substance with household vinegar (i.e., 5% acetic acid solution) would result in rapid neutralization and thus reduce extent of tissue injury. Animals treated with acetic acid demonstrated a more rapid return to physiologic pH (14.69 +/- 4.06 minutes versus 31.62 +/- 2.83 minutes; p < 0.001), increased depth of dermal retention (0.412 +/- 0.136 mm versus 0.214 +/- 0.044 mm; p = 0.015), decreased leukocyte infiltrate (31.0 +/- 5.1 cells/high-power field versus 51.8 +/- 6.8 cells/high-power field; p < 0.001), and improved epithelial regeneration (4.0 +/- 0.6 cell layers versus 1.7 +/- 0.5 cell layers; p < 0.001) when compared with animals treated with water irrigation. No difference was detected in peak pH (10.35 +/- 0.28 pH versus 10.36 +/- 0.25 pH; p = 0.47) nor in rise of skin temperature (maximum temperature, 32.8 degrees C versus 32.9 degrees C; p = 0.33) between acetic acid-neutralized and water-irrigated burn wounds. The observed benefits of treating alkaline burns with 5% acetic acid in the rat model are significant and require clinical testing.

Fast [18F]FDG synthesis by alkaline hydrolysis on a low polarity solid phase support

AbstractThe synthesis of 2‐deoxy‐2‐[18F]fluoro‐D‐glucose ([18F]FDG) has been simplified by the use of a tC18 Sep Pak cartridge to effect purification and hydrolysis of the tetraacetylated [18F]fluoro‐glucose compound ([18F]TAG). After radiolabelling, this derivative was trapped on a solid phase extraction (SPE) cartridge and the residual reaction solvent (CH3CN), reagents (K222, K2CO3,…) and by‐products removed by washing the support with water. After this cleaning step, the acetyl groups were cleaved on the same tC18 column using 2N sodium hydroxide. This fast reaction proceeded near quantitatively (&gt;98%) at room temperature in less than 2 min. The [18F]FDG was then recovered with a small amount of water, neutralized with a slight excess of 2N hydrochloric acid, buffered for pH with a citrate solution and finally purified on a neutral alumina oxide and a second tC18 column. After filtration, the radiochemical yield of this [18F]FDG isotonic solution after more than 100 production runs was found to be very reliable and reproducible (70±6% decay corrected). The synthesis time was about 22 min. Quality controls showed that the radiochemical purity was higher than 98% and in any case no [18F]FDM was detected. Only traces of 2‐chloro‐2‐deoxy‐glucose (ClDG) were found in the final sample (64±9 μg/ batch of 16 ml). [18F]FDG specific activity averaged between 1 and 20 Ci/µmol (EOS). No evaporation and use of ion retardation resin (AG11A8) are required. Moreover, this new approach is suitable for complete remote operation using available single use medical components. Copyright © 2002 John Wiley &amp; Sons, Ltd.

Comparison of some properties of pronethalol and propranolol. 1965.

Comparison of some properties of pronethalol and propranolol. 1965.

Quantitative analysis of methadone and two major metabolites in hair by positive chemical ionization ion trap mass spectrometry.

A sensitive and specific method for the quantitative determination of D,L-methadone (MD) and its metabolites, D,L-2-ethyl-1,5-dimethyl-3, 3-diphenylpyrrolinium (EDDP) and D,L-2-ethyl-5-methyl-3, 3-diphenyl-1-pyrroline (EMDP), in hair has been developed. Deuterated internal standards of MD, EMDP, and EDDP were added to 20-mg hair samples and digested overnight at room temperature with 1N sodium hydroxide. Calibration standards containing known concentrations of MD, EMDP, and EDDP dried onto human hair were also digested. Digest solutions were extracted by a liquid-liquid extraction procedure and analyzed with splitless injection on a Finnigan MagnumTM ion trap mass spectrometer. Chromatographic separation was achieved with helium carrier gas on a DB-5MS-30M-0.25-micron capillary column. Positive chemicaionization was used with acetone as the reagent gas. The assay was linear from 0.5 ng/mg (MD and EDDP) or 1.0 ng/mg (EMDP) to 50.0 ng/mg of human hair with correlation coefficients greater than 0.99. Intra-assay and interassay coefficients of variation were determined to be less than 20% for all three analytes at 2.0 and 10.0 ng/mg of hair. Recovery was estimated to be greater than 70% (MD and EDDP) and 53% (EMDP) at 2.0 and 10.0 ng/mg of hair. The method has been applied to the analysis of both human and rat hair. Male long-Evans rats were shaved prior to dosing to obtain their drug-free hair. Animals were then administered 15 mg/kg MD by intraperitoneal injection daily for five days. Fourteen days after the first dose, hair was collected and analyzed for MD, EMDP, and EDDP. The mean plus standard error of the mean (SEM; n = 3) concentrations of MD and EDDP in pigmented hair were 31.1 ng/mg +/- 9.6 ng/mg and 8.6 +/- 2.4 ng/mg, respectively. EMDP was detected in the hair of one of three rats. In another experiment, hair was collected from two human subjects who had received long-term methadone therapy for the treatment of heroin addiction. Subject A received 60 mg of methadone daily for at least six months; subject B received 80 mg of methadone daily for at least six months. The hair concentrations of MD were 10.1 ng/mg and 21.0 ng/mg for Subjects A and B, respectively. The hair concentrations of EDDP were 0.5 ng/mg and 2.6 ng/mg for Subjects A and B, respectively. EMDP was not detected in the hair of these two subjects. This method is being used to evaluate the incorporation of MD, EMDP, and EDDP in human and rat hair in dose-response studies.

Measurement of organ blood flow with coloured microspheres in the rat

The aim was to establish a method for measuring organ blood flow in rats using commercially available, coloured, dye extraction microspheres. A mixture of radiolabelled and dye extraction microspheres was infused into rats at rest (basal) and during intravenous administration of either angiotensin II (0.5 microgram.kg-1.min-1) or isoprenaline [12.5 ng.(g0.74)-1.min-1]. Tissues were removed and placed in test tubes, counted for radioactivity, then digested with 2N sodium hydroxide. Within the same tube, microspheres were isolated using centrifugation and the dye was extracted with dimethylformamide. The dye was quantified by spectrophotometry. Recovery of microspheres averaged greater than 95% for all tissues studied; larger reagent volumes were required to achieve this level of recovery from white adipose tissue. Statistical analyses showed excellent correlations between blood flow values obtained by the dye extraction and radiolabelled microsphere techniques. Blood flow values obtained with the radioactive technique tended to be slightly higher. There were no differences in the results obtained with the two techniques when they were simultaneously used to measure changes in organ blood flow induced by angiotensin II or isoprenaline. The coloured, dye extraction microsphere technique accurately measured organ blood flow in rats. This technique is potentially useful for estimating blood flow in any animal, even if tissue sample size is limited.

Novel pyranopyridine derivatives from an enaminone

AbstractThe pyranopyridine derivatives 2 and 15B were synthesized from enaminone 1 and hydroxylamine in the presence of 2N and 1N aqueous sodium hydroxide solutions, and consecutive reactions with these compounds are described.

Determination of Residual Avoparcin in Chicken Muscle by High Performance Liquid Chromatography

An analytical method was developed for residual avoparcin in chicken muscle by measuring α- and β-avoparcin, major components of the pharmaceutical preparation of avoparcin, using high performance liquid chromatography (HPLC). Alpha- and β-avoparcin were used as authentic samples after isolation by preparative HPLC. The analytical HPLC was achieved by using a Cosmosil 5C18-AR column (4.6mm×25cm), a mobile phase of 2.5% acetic acid, 0.01M sodium heptane sulfonic acid-acetonitrile (88.5:11.5) (pH 4.0) with UV detection at 280nm. Since the values obtained by HPLC as the sum of α- and β-avoparcin were highly correlated to those obtained by bioassay (r=0.95, n=24), it was suggested that the proposed HPLC method may substitute for the time-consuming bioassay.Avoparcin was extracted from chicken muscle by homogenization in methanol -0.2M sulfuric acid (6:4) followed by centrifugation after pH adjustment to 3 by 1N sodium hydroxide. The supernatant was evaporated to dryness, and the residue was dissolved in water. The aqueous layer was adjusted to pH 3 by adding 1N sodium hydroxide. Then it was purified on a Sep-pak C18 cartridge. The cartridge was washed with water, and retained substances were eluted with 50% methanol. The eluate was evaporated to dryness under reduced pressure. The residue was dissolved in water and determined by HPLC. Recoveries for avoparcin spiked in chicken muscle were 104-99.5% at 2-16μg/g. The detection limit is 0.5μg/g.

Collagen Shields Exacerbate Ulceration of Alkali-Burned Rabbit Corneas

To determine the impact of collagen shields on ulceration of rabbit corneas after alkali burn. After a 60-second 2N sodium hydroxide burn to rabbit corneas, 24-hour collagen shields were placed on the corneas daily for 21 days; control corneas did not receive collagen shields. The extent of corneal ulceration was documented daily for 21 days by slit-lamp examination of treated and control eyes. Three separate studies were performed using collagen shields from two commercial sources. In the three studies, corneas in the collagen shield-treated eyes began to ulcerate sooner than those in the control group; the corneas in collagen shield-treated eyes also began to perforate sooner. At 21 days after alkali injury, the mean (+/- SE) corneal ulceration score in the collagen shield-treated rabbits was 4.1 +/- 0.17 (descemetocele formation) compared with 2.7 +/- 0.28 (midstromal ulceration) in controls. This difference was significant at P < .005. Collagen shield treatment results in marked acceleration of corneal ulceration and perforation after alkali injury.

Fragmentation and solubilization of filamentous appendages of Bacillus cereus spores

Filamentous appendages were removed from the surfaces of Bacillus cereus spores by treatment with sodium thioglycolate and purified by filtration through a glass microfiber paper and a membrane filter. The basic structure of the isolated appendages resembled that of the native appendages on the spores. The results of electron microscopical analysis, amino acid analysis, and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) attested the purity of the preparation. The purified filamentous appendages were fragmented by treatment with 2N sodium hydroxide at 30C but neither with SDS nor mercaptoethanol, and the fragmentation progressed with the prolongation of the treatment period. When observed under an electron microscope, each fragmented appendage appeared to be rod shaped with an apparent axial hole and helical or disk-like arrangement of subunits. In the agar gel immunodiffusion test, a soluble fraction of the appendages obtained by treatment with sodium hydroxide formed only a single precipitation line against the antibody to the intact appendages. The molecular mass of the subunit separated by SDS-PAGE was approximately 10kDa. The 10-kDa protein was distributed over the surface of the intact appendages in immunoelectron microscopy. The antigenicity of the appendage subunits disappeared upon treatment with 2N sodium hydroxide for longer than 24h. Neither intact appendages nor intact spores agglutinated sheep or guinea-pig erythrocytes.

Chemical agents for reducing solubility of silica in 1N sodium hydroxide

A short experimental research project examined the effectiveness of several chemical agents for the control of alkali aggregate damage in concrete. The experimental program was conducted in three stages. The first stage was aimed at rapid evaluation of a number of chemical agents for their effectiveness in preventing dissolution of reactive silica in strong alkaline solutions. Promising chemical agents from Stage 1 were selected for use as admixtures and aggregate pre-treatments for the control of ASR in fresh concrete, and as penetrants for the control of ASR in hardened concrete. The results of the first stage are reported herein. Three chemicals - aluminum sulfate, zinc sulfate, and pyrogallol, were identified to be effective retardants of silica dissolution in a high alkali solution (1N sodium hydroxide). It was found that the concentration of chemical needed to reduce the solubility of silica by comparable proportions was higher for opal than for less reactive Spratts aggregate.

Colonization by Staphylococcus aureus on Chapped Teat Skin: Effect of Iodine and Chlorhexidine Postmilking Disinfectants

The abilities of common postmilking teat disinfectant solutions and a teat skin ointment to retard Staphylococcus aureus colonization and promote healing of chapped skin were studied. Ten Holstein cows, free of S. aureus intramammary infections and mammary epidermal colonization, were used. All teats were experimentally chapped with 1N sodium hydroxide and dipped in S. aureus broth culture of 5 x 106 cfu/ml after three consecutive milkings. Postmilking teat disinfectant treatments were applied, starting after the second application of S. aureus broth culture, and were continued for the next 19 milkings. Quarters of each cow received one of the following postmilking teat treatments: 1% iodine plus 10% glycerin solution; .5% chlorhexidine plus 4.87% glycerin solution; 1% chlorhexidine ointment; and no postmilking treatment. After milking and before treatment application, samples of skin swabbings of the teat end and teat side and samples of milk were collected. Daily teat skin chapping visual scores were made to assess chapping and healing. Teat skin chapping decreased with time, and the decline was similar among treatments. The concentration of S. aureus recovered from teat skin swabbing solutions decreased over time. Staphylococcus aureus were recovered at significantly lower concentrations from swabbing solutions of teats that were dipped with iodine and chlorhexidine solutions as compared with untreated teats. Staphylococcus aureus was in marginally higher concentrations on ointment-treated teats than on dipped teats. Results indicate the importance of using post-milking teat dips on chapped teats and suggest no advantage in applying a disinfectant ointment to chapped teats to reduce S. aureus colonization and improve skin healing.

An HPLC Method for Determination of Atropine in Human Plasma

Abstract A development of a high performance liquid chromatographic method for the determination of atropine in human plasma is presented. Atropine is extracted from plasma basified with 0. 1N sodium hydroxide using chloroform, subsequently subjected to base hydrolysis, followed by derivatization of the generated tropic acid with 4-bromomethyl-7-methoxycoumarin (Br-Mmc). The derivative produced has a strong blue fluorescence at excitation wavelength of 328 nm and emission cutoff filter of 389 nm. d1-Mandelic acid as internal standard (I. S.) was added after hydrolysis. The chromatographic separation was achieved on a reversed phase ODS column with a mobile phase of 33% acetonitrile in 0. 01M ammonium phosphate buffer (pH 5). The minimum quantitative limit was 125 ng/ml of plasma.

Spectrophotometric Determination of Domperidone Using δA Method

Abstract A spectrophotometric method for the assay of domperidone tablets (Motilium(R)−10 mg) is described. The mean percentage found for the active ingredient per tablet was 100.61 ± 1.19. The drug exhibits maximum absorption at 282 nm in 0.5 N-sulphuric acid and at 294 nm in 0.5 N-sodium hydroxide due to keto-enol tautomerism. δA at 300 nm proved to be linearly related to the drug concentration in the range 5-30 μg ml−1 with a coefficient of variation 1.09%.

Simultaneous determination of paraquat and diquat utilizing those oxidation products by high performance liquid chromatography.

Method for the analysis of paraquat and diquat with those oxidation products were studied by high performance liquid chromatography (HPLC) and thin-layer chromatography (TLC). Paraquat and diquat were easily oxidized by potassium ferricyanide in alkaline solution, and the former formed 1, 1'-dimethyl-4, 4'-bipyridyl-2, 2'-dione [I], the latter formed 6, 7-dihydrodipyrido [1, 2-a : 2', 1'-c] pyrazine-4, 9-dione [II]. Oxidative reaction of paraquat and diquat has been carried out in the stirred suspension of 1%-potassium ferricyanide in 9 N-sodium hydroxide at room temperature over 1 min. These oxidation products were determined by HPLC using a reversed phase column packed with Shim-pack CLC-ODS (6.0 mm i.d.×0.15 m) and an ionpairing reagent as a mobile phase with a fluorescence spectroscopic detector. The mobile phase consisted of 0.001 M sodium 1-octanesulfonate in 10% acetonitrile-10 mM phosphate buffer (pH 2.6). The calibration curves gave a good linearity in the range of 0.1-10μg/ml on paraquat and 0.3-10μg/ml on diquat. These oxidation products were separated on silica gel thin-layer chromatogram with a solvent system consisting of chloroform-acetone-methanol (8 : 1 : 1). Rf values of I and II were 0.47 and 0.64, respectively. Detection limits of paraquat and diquat were 20 ng and 10 ng, respectively.

Systemic tetracycline treatment of alkali-induced corneal ulceration in rabbits.

Recent evidence has demonstrated a marked anticollagenolytic effect for the tetracycline antibiotics. We have examined the efficacy of systemic tetracycline hydrochloride in a rabbit model of corneal ulceration. A standard alkali burn (1N sodium hydroxide for 40 s) was delivered to 62 eyes (31 rabbits). Animals were then divided into three groups: group 1 (controls) (ten rabbits [20 eyes]) received no treatment; group 2 (ten rabbits [20 eyes]) received 10 mg/kg/d of tetracycline hydrochloride, given intramuscularly; and group 3 (11 rabbits [22 eyes]) received 50 mg/kg/d. Ulceration occurred in 85% (17/20) of control eyes. The higher dosage of tetracycline was more effective in preventing ulceration than the lower dosage (9.1% vs 55%). Eyes with higher levels of tetracycline in ocular tissues were less likely to ulcerate.

クロム含有リン酸塩ガラスの作製と化学的耐久性

Phosphate glasses containing a large amount of chromium oxide were prepared and their chemical durability was examined. Among various phosphate glasses, metaphosphate glass was chosen as the base glass composition because of its chemical stability. The maximum amount of chromium oxide included in the glass was found to be 23mol%.The chemical durability of these chromium oxide-containing phosphate glasses was excellent. Particularly, the alkali resistance of phosphate glass was imporved by the addition of chromium ions. Both the weight loss and dissolution of chromium ions for the best glass were almost zero in 1N sodium hydroxide aqueous solution after immersing it for 12 hours at 70°C. The fact that these metaphosphate glasses excelled other phosphate glasses in water, acid or alkali resistance was explained based on the difference in glass structure.

Rapid Separation of Milk Whey Proteins by Anion Exchange Chromatography

A fast protein liquid chromatography system was used to fractionate the major proteins of sweet and acid wheys. Fifty to 500μl of whey were fractionated with a stepwise ionic strength gradient using water (buffer A) and increasing concentrations of .7 M sodium acetate (buffer B). Six well-resolved peaks were obtained: 1) amino acids (tentative identification), 2) low molecular weight peptides (tentative identification), 3) highly enriched α-lactalbumin, 4) highly enriched serum albumin 5) electrophoretically pure β-lactoglobulin B, and electrophoretically pure β-lactoglobulin A. A poor baseline or unresolved peaks resulted when .02 M bis-tris or .02 M histidine was used for buffer A and .7 M sodium acetate in .02 M bis-tris or histidine was used for buffer B. When sodium chloride was used in place of sodium acetate, β-lactoglobulins A and B were poorly resolved. The column was cleaned after each run by injecting 2ml of the following reagents: glacial acetic acid, 2N sodium chloride, 2N sodium hydroxide, 2N sodium chloride, 2% detergent, and 100% acetonitrile. Time required to run each sample including column cleanup was 40min.

Application of Van Soest Acid Detergent Fiber Method for Analysis of Shellfish Chitin

The Van Soest acid detergent fiber method was compared with the modified Welinder method for chitin analysis of Alaskan crab and shrimp meals to determine whether chitin constituted a significant fibrous component of shellfish meals. In the Welinder method, chitin is determined gravimetrically following decalcification and deproteinization with .1 M ethylenediaminetetraacetic acid and 2N sodium hydroxide, respectively, Chitin is a fibrous component of shellfish meals, and the Van Soest acid detergent fiber method is acceptable for determination of shellfish chitin.

Compatibility of furosemide with aminoglycoside admixtures

The compatibility of furosemide with i.v. admixtures containing each of five different aminoglycosides was studied. Admixtures of amikacin 2 mg/ml, gentamicin 1.6 mg/ml, kanamycin 2 mg/ml, netilmicin 1.5 mg/ml, and tobramycin 1.6 mg/ml (as the sulfate salts) were prepared in both 5% dextrose injection and 0.9% sodium chloride injection in minibags. Furosemide injection 4 ml (40 mg) was then added to each admixture, and the admixtures were examined visually and microscopically for precipitate. The macroscopic and microscopic evaluations were repeated 15 minutes and 24 hours after mixing. To simulate Y-site injection of furosemide, furosemide injection 1 ml (10 mg) was added to 1 ml of each aminoglycoside admixture in a syringe. For admixtures in which precipitates formed, the pH was recorded before and after adding furosemide to subsequent admixtures and also after dropwise addition of 1N sodium hydroxide until the precipitate dissolved. Precipitates were identified using spectrophotometric analysis and melting point determinations. Addition of furosemide resulted in a precipitate only in admixtures containing gentamicin sulfate or netilmicin sulfate; the results for the simulated Y-site injection study were the same. Spectrophotometric analysis and melting point determinations revealed that the precipitate was furosemide. Because furosemide precipitates when added to admixtures containing either gentamicin sulfate or netilmicin sulfate in 5% dextrose injection or 0.9% sodium chloride injection, furosemide should be administered separately or the i.v. tubing should be flushed thoroughly before and after administering this drug via a Y-injection site.

Modified Method for Electron Capture Gas-Liquid Chromatographic Determination of Diethylstilbestrol Residues in Urine of Fattened Bulls

A gas-liquid chromatographic (GLC) method with electron capture (EC) detection was developed for determining diethylstilbestrol residues in the urine of fattened bulls. Diethylstilbestrol (DES) is extracted into benzene, and then into 1N sodium hydroxide. The pH of the phenolic fraction (alkaline phase) is adjusted to 10.2 and DES is extracted again into benzene. Sample extracts are cleaned up on silica gel. Trifluoroacetic anhydride (TFAA) is used as acylation reagent, and the derivatized sample is chromatographed on a 3% OV-17 column and measured with a 63Ni EC detector. The method is suitable for determining residues at levels as low as 2 ppb.