Reagent tablets

In the Penzyme test, freeze-dried Streptomyces oo-carboxypeptidase is placed in sealed vials to which the milk sample is added. A preliminary incubation is carried out for 5 min at 47 C to cause some inactivation of the enzyme molecules. The degree of inactivation is dependent on the amount of -lactams presumed to be present in the milk sample. Subsequent addition of a reagent tablet containing synthetic o-alanine oligopeptide and o-amino acid oxidase followed by reincubation at 47 C for 15 min results in the release of o-alanine, its amount... 

Povidone-iodine gives a positive reaction with an ortho-toluidine reagent used to detect blood in the urine, for example Hematest reagent tablets or dipsticks (SEDA-11, 488 47). 

A normal commercial DPD reagent tablet without potassium iodide additive is placed with tweezers in the cuvette of a normal commercial comparator, and a measured quantity of the water to be analyzed, e.g. 1, 2 or 5 ml, is added. 

BM Hitachi 737 300 1,200 23 3-20 30,37 AMW,P sampling option unit dose dry tablet reagent... 

The metal lost from the inside of pumps, reaction vessels, pipework, etc. usually contaminates the product. The implications of this depend upon the product. Ppb levels of iron can discolor white plastics, though at this level the effect is purely cosmetic. Ppm levels of iron and other metals affect the taste of beer. Products sold to compositional requirements (such as reagent-grade acids) can be spoiled by metal pick-up. Pharmaceutical products for human use are often white tablets or powders and are easily discolored by slight contamination by corrosion products. 

Buyuktimkin and Buyuktimkin [20] described a spectrophotometric method of assay of penicillamine and its tablets. An aqueous solution of 100 mg/mL of penicillamine was added to ethanolic 5 mM Sanger reagent (l-fluoro-2,4-dinitrobenzene), solid NaHC03, and water. The solution was diluted and heated at 70 °C for 45 min. After cooling, the solution was diluted with 3% ethanolic HC1. The absorbance of the resulting yellow complex was measured at 355 nm (molar absorptivity = 19,721). Recovery of the drug from commercial tablets was 99.1 0.7%. 

Min et al. [23] determined primaquine phosphate, in tablets, by an ultraviolet spectrophotometric method. Sample was treated with 0.01 M hydrochloric acid and the resulting solution (500 pg/mL) was diluted to 50 mL with 0.01 M hydrochloric acid. The absorbance of the solution was measured at 265 nm versus a reagent blank. Beer s law was obeyed from 8 to 20 pg/mL of primaquine phosphate. Recovery was 100.2% (n = 5) and the coefficient of variation was 0.5%. Results were consistent with those obtained by a pharmacopoeial method. 

Sastry et al. [41] used a new spectrophotometric method for the estimation of primaquine, using 3-methylbenzothiazolin-2-one hydrazone. An aqueous extract of the sample of powdered tablets (containing 50 pg/mL of primaquine phosphate was mixed with 1 mL each of aqueous 8.5 mM 3-methylbenzothiazolin-2-one hydrazone and 11.84 mM CelV (in 0.72 M sulfuric acid), the mixture was diluted to 10 mL, and the absorbance was measured at 510 nm versus a reagent blank. Beer s law was obeyed for 0.7-12 pg/mL of the drug and for 50 pg, the coefficient of variation was 0.52%i (n = 8). Other antimalarials and pharmaceutical adjuvants did not interfere. 

Rao et al. [46] reported the use of a spectrophotometric method for the determination of primaquine phosphate with ninhydrin. Standard solution of 0.01% primaquine phosphate solution (3 mL) or solution prepared from the drug or its tablets was mixed with 2 mL of water, 5 mL of 2-methoxyethanol and then with 4 mL of ninhydrin reagent. The mixture was boiled for 35 min, and, after cooling and dilution to 25 mL with water, the absorbance was measured at 570 nm versus a reagent blank. Beer s law was obeyed from 4 to 20 pg/mL with recoveries of 99.4— 100.2% for 25 mg of primaquine phosphate. 

El-Kommos and Emara [47] determined primaquine and other secondary aromatic amines pharmaceuticals by a spectrophotometric method using 4-dimethyl amino cinnamaldehyde. The reaction of the reagent with primaquine and with the other amines was investigated. Powdered tablets were extracted with methanolic 0.1 M perchloric acid. The extract was mixed 1 1 with methanolic 0.2% of 4-dimethyl amino cinnamaldehyde and the mixture was diluted with methanol before measurement of the absorbance at 670 nm for primaquine phosphate. Beer s law was obeyed for 2-20 pg/mL of primaquine. The pink and green color formed with primaquine was stable for at least 24 h. Recoveries were good. Amodiaquine did not interfere with the determination of primaquine. 

Sastry et al. [50] estimated primaquine in its tablet formulation. Powdered tablets equivalent to 100 mg of primaquine phosphate were dissolved in water, filtered, and filtrate was diluted to 100 mL with water. Portions of the solution were shaken with 3 mL of 5 mM brucine-0.16 M sulfuric acid, 1.5 mL of 5 mM sodium periodate and 2 mL of 1.2 M sulfuric acid and diluted to 9 mL with water. The solution was set aside for 20 min in a boiling water bath, cooled, and diluted to 10 mL with water. The absorbance was measured at 510 nm versus a reagent blank. Beer s law was obeyed from 20 to 140 pg/mL of primaquine phosphate. The coefficient of variation was 1.56% (n = 8). Recovery was 99.2%. 

Catalysts. Cupric oxide was prepared by thermal decomposition of reagent grade copper nitrate (Wako Pure Chem.Inc.Ltd.) at 400°C in air for 4 hrs. Magnesium oxide was commercially available reagent grade powder (Kanto Chemical Co.Ltd.). The oxides powders were pressed into tablets and crushed and 24-42 mesh granules were used as catalysts. 

Diloxanide furoate was determined by Sane al. using a simple spectrophotometric method [28]. The drug was extracted from tablets with ethanol, or was filtered from a suspension and dissolved in ethanol. The resulting solution was mixed with 6% aqueous sodium hydroxide and Folin-Ciocalteu reagent, or with a 1% solution of sodium nitroprusside in aqueous 10% sodium hydroxide. The complexes formed had absorbance maxima at 650 run, or at 675 nm, respectively. 

Sastry et al. used iodine and isonicotinic acid hydrazide for the spectrophotometric determination of diloxanide furoate in tablets and in syrups [30]. Powdered tablets or syrup were dissolved in methanol and hydrolyzed under reflux with dilute hydrochloric acid. The mixture was cooled, and excess HCI removed under vacuum. The hydrolysate was dissolved in and diluted with water. Iodine solution and the isoniazid solution were added at two minute intervals to a potassium h) drogen phthalate/HCl buffer solution (pH 3), and diluted with water. The solution was set aside for 10 minutes, whereupon the absorbance was measured at 630 nm against a reagent blank. 

There are several options for the reagents used in color development including solution, powder, and tablets. Among these,... 

The development of achiral lanthanide shift reagents preceded that of chiral LSRs. It was demonstrated86 in 1969 that paramagnetic Eu(thd)3 and Eu(fod)3 (Tablet), as well as the... 

When attempting to convert a manual method into an automated method, there are certain elements, such as tablet size and solvent selection, which will have an impact on the ease of the conversion from manual to automated. For instance, some of the elements of an assay method that would make it easier to automate would be that the dosage form fits into a test tube the extraction uses neutral media or acid not more concentrated than 0.1 M makes use of nonvolatile, low-toxicity solvents does not use surfactants and uses premixed, room-temperature solvents. Some of the elements of a dissolution method that would make it easier to automate would be that the dosage form fits in the sample carousel, does not use media more concentrated than 0.1 M acid, does not use isopropanol or surfactant in large quantities, uses magnetic sinkers or no sinkers at all, and uses no or minimal reagent addition volumes for pH control. 

What mass of 3.0 wt% H202 solution is required to provide a 50% excess of reagent for Reaction 1-5 with 12 dietary iron tablets ... 

Most active principles and pharmaceutical forms are processed in the presence of organic solvents or reagents. The current regulations on products generally restrict to a few p.p.m. the amount of residual solvent. This very low concentration level could favour the CO2 utilization when non-polar compounds have to be eliminated. On the other hand, the elimination of residual solvents from tablets, films or other pharmaceutical preparations in which organic solvent are involved has been addressed [15]. Another application is related to the removal of residues from medical materials such as monomers, additives or polymerization residues from polymers or elastomers. Purification of active principles includes elimination of other undesired molecules pesticides from some vegetal extracts, and antibacterials suspected of toxic co-extracts from natural sources. 

Amerlite signal reagent (Johnson and Johnson Clinical Diagnostics) is supplied as separate bottles of buffer and substrate tablets. One A and one B substrate tablet (cat. no. LAN.4401) are dissolved in each bottle of substrate buffer (cat no. LAN. 4402) prior to use. This reagent is stable for a day at room temperature providing it is kept in the dark glass bottle... 

Tablets HPLC Derivatize with homochiral reagent Silica n-Hexane-CHjC l -IPA (100 100 4) 240 nm Resolved epimers along with dexamethasone...

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