A new spectrophotometric method based on the oxidation reaction between iodide and iodate in the presence of carboxylic acid form of losartan potassium (LP) has been developed for the estimation of LP in pharmaceutical products. HPLC/MS method, kinetic studies and central composite design method was used for formation reactions, equilibration and determination of stability duration and experimental conditions, respectively. Developed spectrophotometric method was validated. The equilibration period was calculated as 10 minutes. 0.05 M KI and 0.003 M KIO3 and amount was calculated as 1.953 mL (0.0195 M) and 1.961 mL (0.00117 M), respectively; and temperature was measured as 32.3 °C. It was revealed that the method was linear between 4-30 μg/mL with correlation coefficient of 0.9996. LOD and LOQ parameters were calculated as 0.61 and 1.85 μg/mL,respectively. Pharmaceutical preparations were analyzed by the developed kinetic spectrophotometric method. The obtained results ranged between 94.9 % and 100.9 %.
Keywords: losartan potassium, central composite design, spectrophotometric method
Hypertension, an important and independent risk factor for cardiovascular disease, is best managed by maintaining blood pressure above 140/90 mmHg[1].Including angiotensin II receptors, many of the receptor antagonists are the block receptors which control the blood pressure[2].The new member of antihypertensive agents called as angiotensin II receptor antagonist are not exhibit any significant side effects[3].Losartan potassium (LP) is the first an angiotensin II receptor antagonist and chemically is used as an antihypertensive agentthat specifically blocks the angiotensin II type 1 receptor[4].Simple and rapid analytical methods must be developed ...
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...d reported in the literature[26]. LP was also one of the sartan group drugs including mentioned functional group. But the oxidation reaction between IO3 and LP has not been investigated yet. Thus, the aim of this work was to develop, optimize and validate a specific, accurate, precise and sensitive a new spectrophotometric method based on the oxidation reaction between iodide and iodate in the presence of carboxylic acid form of LP yielding a yellow-colored product (λmax=286 nm) to determine LP in pharmaceutical tablets. The optimization of the reaction conditions was performed by applying a response surface methodology based on the central composite design which can save the time and effort by the estimation of the optimum conditions. In addition, the kinetic study of reaction was executed for avoid theinterference of colored and/or turbidity background of samples.
The IR spectrum RM-02-CC2 was obtained. The spectrum consisted of a carbonyl peak, an aromatic carbon-carbon double bond peak, and a sp2 hybridized carbon and hydrogen bond peak at 1713, 1598, and 734. These functional groups are all present in 9-flourenone. The carbonyl group specifically was important because fluorenone was the only that contained a carbonyl group. The Identity was further confirmed by the melting point, 79-80˚C. This value is similar to the known value 84˚C2. The melting point observed during the experiment is greater than the known because the sample is slightly impure. This impurity is caused by presence of fluorene on the tip of the columns. As stated before, the tip of the column needs to be manage to ensure pure products. The presence of fluorene would increase the temperature as seen in the melting point results because the melting point of this compound is greater than fluorenone. Overall, both compounds were separated with column chromatography and presented reasonable yields for both products. Column chromatography is a useful technique to separate mixtures with both large and small quantities. Unlike TLC, column chromatography and be used for large amounts of
Every 5 minutes, a small amount of mixture was dissolved in acetone (0.5 mL) and was spotted onto a thin layer chromatography (TLC) plate, which contained an eluent mixture of ethyl acetate (2 mL) and hexanes (8 mL). The bezaldehyde disappearance was monitored under an ultraviolet (UV) light. Water (10 mL) was added after the reaction was complete, and vacuum filtrated with a Buchner funnel. Cold ethanol (5 mL) was added drop-by-drop to the dried solid and stirred at room temperature for about 10 minutes. Then, the solution was removed from the stirrer and place in an ice bath until recrystallization. The recrystallized product was dried under vacuum filtration and the 0.057 g (0.22 mmol, 43%) product was analyzed via FTIR and 1H NMR
The purpose of the Unknown White Compound Lab was to identify the unknown compound by performing several experiments. Conducting a solubility test, flame test, pH paper test, ion test, pH probe test, conductivity probe test, and synthesizing the compound will accurately identified the unknown compound. In order to narrow down the possible compounds, the solubility test was used to determine that the compound was soluble in water. Next, the flame test was used to compare the unknown compound to other known compounds such as potassium chloride, sodium chloride, and calcium carbonate. The flame test concluded that the cation in the unknown compound was potassium. Following, pH paper was used to determine the compound to be neutral and slightly
This experiment involves performing various techniques, including heating under reflux, separation, drying, distillation, gas chromatography (GC), infrared spectroscopy (IR spectroscopy), and nuclear magnetic resonance (1H NMR). Heating under reflux is important to overcome any activation barrier of energy that may be present in order to complete the reaction.
A major physiological process that the human body implements to control blood pressure is through the renin-angiotensin-aldosterone regulatory pathway. The kidneys, which are a major location for water retention regulation (and through changes in blood volume regulate blood pressure), notice decreases in blood pressure and release renin, an enzyme that alters the conformation of proteins, which converts angiotensinogen into angiotensin I. Next, angiotensin I is altered into the conformation of angiotensin II by the action of angiotensin converting enzyme. Angiotensin II then causes many physiological effects that in turn increase blood pressure. These include causing cardiac hypertrophy, vasoconstriction throughout the body, stimulation of the adrenal cortex to release aldosterone and stimulation of the pituitary to release anti-diuretic hormone, each of which cause the retention of sodium and water in the kidneys. In an attempt to help regulate the blood pressure of those with hypertension, drugs have been designed that focus on the angiotensin converting enzyme. By decreasing the action of this enzyme from converting angiotensin I into angiotensin II, the physiological response to increase blood pressure that angiotensin II ensues can be greatly decreased. Through a decrease in salt and fluid retention and systemic vasodilation, blood pressure can be effectively decreased.
The percentage of crude acetaminophen was 77.78%. The infrared spectrum of synthesised acetaminophen was similar to the USP grade acetaminophen. The functional groups and type of bonds in acetaminophen were identified. The NH bond stretching at wavenumber 3325.81 cm-1 and 3325.44 cm-1 in USP grade acetaminophen and synthesised acetaminophen. The bending of NH bond formed a band around 1610 cm-1. The presence of carbonyl group in both synthesised and USP grade acetaminophen gave a peak at wavenumber 1663.50 cm-1 and 1664.71 cm-1. Acetaminophen is para-disubstitution, it formed a peak around wavenumber 837cm-1. There were two small broad peaks found in both spectrum around wavenumber 3160 cm-1 to 3210 cm-1, this indicated the presence of OH group in the solutions. The melting point of synthesised and USP grade acetaminophen were 160 ℃-170 ℃ and 160 ℃-173 ℃. Both of these acetaminophen do not comply with the USP monograph melting point which is 168 ℃ to 172 ℃. This indicated there are some impurity presence in both of the synthesised and USP grade acetaminophen. The maximum wavelength of synthesised acetaminophen was 244.0 nm which was close to the wavelength of USP grade acetaminophen. The retention factor of synthesised and USP grade acetaminophen were 0.93 and 0.94. This showed that the purity of synthesised acetaminophen was similar to the USP grade acetaminophen. The absorbance value of synthesised and USP grade
In order to ensure the most accurate data, a purification was performed by the process of recrystallization. To perform the recrystallization the powder was dissolved in a minimal amount of hot ethanol/H2O solvent that allowed the unknown powder to crystallize properly when cooled. This process allowed for the removal of soluble impurities when suction filtered. A sample of the unknown acid was weighed at 8.24 g, and it was found that 164ml of a 40% ethanol, 60% H20 solvent dissolved the 8.24 g of unknown acid when heated. The beaker containing the dissolved acid was then placed in a beaker containing ice, allowing the unknown acid to recrystallized. After vacuum filtration, the recovered unknown was dried and weighed at 6.92 g. The percent recovery was determined by the following calculation: (8.24--6.92)8.24 x 100% = 16% loss = 84% recovery of unknown.
The purpose of this lab is to determine the density of a solid and an unknown liquid in order to determine the unknowns from a list of substances provided in the lab instruction. A method to identify the substance is to figure out the density (d=m/v) where d is the density equals to the mass divided by the volume of the substance. When measuring the mass, reset the balance to zero to obtain only the mass of the object in grams (g) and not anything else. When measuring the volume, read at the meniscus for an accurate measurement.
Spectrophotometry is a widely used method to calculate how much light is absorbed by a chemical substance. This is done by measuring the intensity of light as it passes through a sample solution. The principle of this method is that a compound absorbs or transmits light over a certain wavelength from which the measurement can be used to calculate the concentration of a known chemical substance.
After the IR was obtained, analyzed and compared to reference spectrums, and the boiling point was compared to the boiling points in the chart, it was concluded that the unknown product from the reaction was 2-methyl-2-heptanol. The boiling point of 2-methyl-2-heptanol is 162°C, which is between the range of the boiling point obtained
...t cannot be ignored. Uncontrollable hypertension can be very dangerous as it may lead to many other diseases such as heart failure, stroke and diabetes. Therefore, people should have medical check-up regularly on hypertension. As written above, the pathophysiology of hypertension is due to renin-angiotensin-aldosterone-system. Others like cardiac output and peripheral resistance and endothelial dysfunction can be also related to the pathophysiology of hypertension. Drug like losartan is used to treat hypertension. It acts on the renin-angiotensin-aldosterone-system by competing with angiotensin II to bind to AT1 receptors and thus stopping the production of aldosterone that would increase the blood pressure. Lastly, this drug should be taken accordingly with the advices from doctors and pharmacists as some people may have undergo side effects and allergic reactions.
Benedict, Biuret, Iodine and brown paper bag tests were conducted in order to identify various macromolecules which might be present in the two unknown substances given. Qualitative data was gathered on the bases of clarity, viscosity, odor, state of matter and most importantly color change. The data gathered was then complied in table two of this lab.
Craig, D. Q. (2002). Pharmaceutical Applications of Micro-Thermal Analysis. Journal of Pharmaceutical Science, 91(5), 1201-1213.
Gusdinar T. COMPLEXOMETRIC TITRATION An application method of Inorganic Pharmaceutical Analysis [homepage on the internet] . No date. [cited 2014 Mar 20]. Available from: http://download.fa.itb.ac.id/filenya/Handout%20Kuliah/Inorganic%20Pharmaceutical%20Analysis%202008/English%20Version/05.%20COMPLEXOMETRIC%20TITRATION.pdf.
The inorganic analysis is the most applicable qualitative analysis for it applies to non-carbon chemistry which includes metals, metalloids, hydrogen ions etc… Thus it is used the majority of the time. The techniques are not limited to instrumental methods such as organic qualitative analysis. It uses both, instrumental and/or manual methods. In certain cases it is necessary to only identify certain elements, ions or compounds of the sample, for which special...