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Philippe Ackerer - One of the best experts on this subject based on the ideXlab platform.
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the Dissolution anisotropy of pyroxenes experimental validation of a stochastic Dissolution model based on enstatite Dissolution
Journal of Physical Chemistry C, 2020Co-Authors: Arnaud Bouissonnie, Damien Daval, Francois Guyot, Philippe AckererAbstract:The understanding of the atomic-scale mechanisms controlling silicate Dissolution represents a necessary prerequisite for the success of upscaling exercises aimed at predicting the rates of water–s...
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the Dissolution anisotropy of pyroxenes experimental validation of a stochastic Dissolution model based on enstatite Dissolution
Journal of Physical Chemistry C, 2020Co-Authors: Arnaud Bouissonnie, Damien Daval, Francois Guyot, Philippe AckererAbstract:The understanding of the atomic-scale mechanisms controlling silicate Dissolution represents a necessary prerequisite for the success of upscaling exercises aimed at predicting the rates of water-silicate interactions over large space and time scales. In that respect, it has been recently shown that physically-based stochastic models of crystal Dissolution at the atomic scale represent a promising alternative to the conventional treatment of silicate Dissolution rates, which consists in using empirical rate laws adjusted to the results of powder Dissolution experiments. However, most stochastic simulations conducted so far have been based on simple cubic solid structure, and very few were directed to ascertaining the extent to which the simulation outputs quantitatively compare to experimental measurements. In the present study, we take advantage of the anisotropic crystallographic structure and reactivity of chain silicates (pyroxenes) to tackle this issue. Face-specific enstatite Dissolution experiments...
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the Dissolution anisotropy of pyroxenes experimental validation of a stochastic Dissolution model based on enstatite Dissolution
The Journal of Physical Chemistry, 2020Co-Authors: Arnaud Bouissonnie, Damien Daval, Francois Guyot, Philippe AckererAbstract:The understanding of the atomic-scale mechanisms controlling silicate Dissolution represents a necessary prerequisite for the success of upscaling exercises aimed at predicting the rates of water–silicate interactions over large space and time scales. In that respect, it has been recently shown that physically based stochastic models of crystal Dissolution at the atomic scale represent a promising alternative to the conventional treatment of silicate Dissolution rates, which consists in using empirical rate laws adjusted to the results of powder Dissolution experiments. However, most stochastic simulations conducted so far have been based on simple cubic solid structure, and very few were directed to ascertaining the extent to which the simulation outputs quantitatively compare to experimental measurements. In the present study, we take advantage of the anisotropic crystallographic structure and reactivity of chain silicates (pyroxenes) to tackle this issue. Face-specific enstatite Dissolution experiments conducted at pH 0 and 90 °C reveal that the face-specific Dissolution rates observe the following trend: r⁽⁰⁰¹⁾ ≫ r⁽²¹⁰⁾ > r⁽⁰¹⁰⁾ ≥ r⁽¹⁰⁰⁾. Electron microscopy characterizations additionally show that lenticular etch pits elongated following the c axis grow on (hk0) faces, and that nanometer-thick amorphous Mg-depleted layers cover the reacted enstatite surfaces. A stochastic model was developed, and we show that simulations conducted with bond-breaking probability ratios (and therefore, activation energy differences) that are consistent with the existing literature regarding the hydrolysis of Mg–O–Mg, Mg–O–Si, and Si–O–Si bonds can quantitatively account for the measured Dissolution rates. In addition, the lenticular shape, the orientation, and the symmetry of the pits generated numerically on (hk0) faces are also consistent with those observed experimentally, while predicting the formation of Mg-depleted surface layers. As a consequence, this study provides a first milestone to the application of stochastic simulations to investigate the Dissolution of pyroxenes.
Francois Guyot - One of the best experts on this subject based on the ideXlab platform.
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the Dissolution anisotropy of pyroxenes experimental validation of a stochastic Dissolution model based on enstatite Dissolution
Journal of Physical Chemistry C, 2020Co-Authors: Arnaud Bouissonnie, Damien Daval, Francois Guyot, Philippe AckererAbstract:The understanding of the atomic-scale mechanisms controlling silicate Dissolution represents a necessary prerequisite for the success of upscaling exercises aimed at predicting the rates of water–s...
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the Dissolution anisotropy of pyroxenes experimental validation of a stochastic Dissolution model based on enstatite Dissolution
Journal of Physical Chemistry C, 2020Co-Authors: Arnaud Bouissonnie, Damien Daval, Francois Guyot, Philippe AckererAbstract:The understanding of the atomic-scale mechanisms controlling silicate Dissolution represents a necessary prerequisite for the success of upscaling exercises aimed at predicting the rates of water-silicate interactions over large space and time scales. In that respect, it has been recently shown that physically-based stochastic models of crystal Dissolution at the atomic scale represent a promising alternative to the conventional treatment of silicate Dissolution rates, which consists in using empirical rate laws adjusted to the results of powder Dissolution experiments. However, most stochastic simulations conducted so far have been based on simple cubic solid structure, and very few were directed to ascertaining the extent to which the simulation outputs quantitatively compare to experimental measurements. In the present study, we take advantage of the anisotropic crystallographic structure and reactivity of chain silicates (pyroxenes) to tackle this issue. Face-specific enstatite Dissolution experiments...
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the Dissolution anisotropy of pyroxenes experimental validation of a stochastic Dissolution model based on enstatite Dissolution
The Journal of Physical Chemistry, 2020Co-Authors: Arnaud Bouissonnie, Damien Daval, Francois Guyot, Philippe AckererAbstract:The understanding of the atomic-scale mechanisms controlling silicate Dissolution represents a necessary prerequisite for the success of upscaling exercises aimed at predicting the rates of water–silicate interactions over large space and time scales. In that respect, it has been recently shown that physically based stochastic models of crystal Dissolution at the atomic scale represent a promising alternative to the conventional treatment of silicate Dissolution rates, which consists in using empirical rate laws adjusted to the results of powder Dissolution experiments. However, most stochastic simulations conducted so far have been based on simple cubic solid structure, and very few were directed to ascertaining the extent to which the simulation outputs quantitatively compare to experimental measurements. In the present study, we take advantage of the anisotropic crystallographic structure and reactivity of chain silicates (pyroxenes) to tackle this issue. Face-specific enstatite Dissolution experiments conducted at pH 0 and 90 °C reveal that the face-specific Dissolution rates observe the following trend: r⁽⁰⁰¹⁾ ≫ r⁽²¹⁰⁾ > r⁽⁰¹⁰⁾ ≥ r⁽¹⁰⁰⁾. Electron microscopy characterizations additionally show that lenticular etch pits elongated following the c axis grow on (hk0) faces, and that nanometer-thick amorphous Mg-depleted layers cover the reacted enstatite surfaces. A stochastic model was developed, and we show that simulations conducted with bond-breaking probability ratios (and therefore, activation energy differences) that are consistent with the existing literature regarding the hydrolysis of Mg–O–Mg, Mg–O–Si, and Si–O–Si bonds can quantitatively account for the measured Dissolution rates. In addition, the lenticular shape, the orientation, and the symmetry of the pits generated numerically on (hk0) faces are also consistent with those observed experimentally, while predicting the formation of Mg-depleted surface layers. As a consequence, this study provides a first milestone to the application of stochastic simulations to investigate the Dissolution of pyroxenes.
Suparman Suparman - One of the best experts on this subject based on the ideXlab platform.
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PENGARUH PENAMBAHAN SODIUM LAURIL SULFAT (SLS) SEBAGAI SURFAKTAN TERHADAP SIFAT FISIK DAN UJI DISOLUSI TABLET KETOPROFEN
'Lembaga Publikasi Ilmiah dan Penerbitan Universitas Muhammadiyah Purwokerto', 2012Co-Authors: Pratama, Adithya Wahyu, Siswanto Agus, Suparman SuparmanAbstract:ABSTRAK Ketoprofen (asam 2-(3-benzoilfenil) propanoat) adalah turunan asam propionat dengan khasiat analgesic, antipiretik, dan antiinflamasi yang cukup baik namun mempunyai kelarutan yang praktis tidak larut dalam air. Penelitian ini bertujuan untuk meningkatkan kecepatan disolusi dan pengaruhnya terhadap sifat fisik tablet Ketoprofen menggunakan Sodium lauril sulfat sebagai surfaktan. Sodium lauril sulfat merupakan surfaktan yang dapat digunakan untuk meningkatkan pembasahan dan laju disolusi. Penelitian ini dilakukan dengan membuat empat formula tablet Ketoprofen dengan konsentrasi Sodium lauril sulfat yang berbeda (0%, 0,5%, 1%, dan 1,5%) sebagai bahan pembasah. Sebagai kontrol digunakan Ketoprofen tanpa penambahan Sodium lauril sulfat. Tablet dibuat dengan metode granulasi basah. Tablet yang dihasilkan diuji sifat fisik (keseragaman bobot, kekerasan, kerapuhan, dan waktu hancur tablet) dan uji disolusi. Uji disolusi dilakukan dengan metode dayung dengan medium disolusi dapar fosfat pH 7,2 dengan kecepatan putar 100 rpm pada suhu 37±0,5ºC selama 60 menit dan parameter uji disolusi yang dipakai adalah Dissolution Efficiency atau DE30 (%). Data yang diperoleh kemudian dianalisis secara statistik menggunakan Analisa Varian (ANOVA) satu jalan dan uji BNT (Beda Nyata Terkecil) pada data yang memiliki perbedaan bermakna dengan tingkat kepercayaan 95%. Hasil penelitian ini menunjukan bahwa penambahan sodium lauril sulfat tidak berpengaruh terhadap uji kekerasan tablet, uji kerapuhan dan uji keseragaman bobot tablet tapi berpengaruh terhadap uji waktu hancur yaitu semakin banyak sodium lauril sulfat yang ditambahkan semakin cepat pula waktu hancurnya, dan laju disolusi tablet semakin besar pula. Persentase ketoprofen terlarut pada menit ke-30 formula I, II, III, dan IV berturut-turut adalah 14,64% ; 29,66% ; 32,06% ; 35,81%. Kata kunci: sodium lauril sulfat, tablet, ketoprofen, disolusi. ABSTRACT Ketoprofen (acid 2-(3-benzoilfenil) propanoat) was derivated of propionat acid which has analgesic, antipyretic, and anti-inflammatory with poor solubillity in water. This research allowed to increase the Dissolution rate of ketoprofen tablets and effect on the physical characteristic by adding sodium lauril sulfat as surfactant. Sodium lauryl sulfat is a surfactant that can be used to improve wetting and Dissolution rate. This study was done with make four formula of ketoprofen tablets by different concentration of sodium lauryl sulfat (0%, 0,5%, 1%, and 1,5%) as a wetting agent. Ketoprofen without sodium lauryl sulfat was used as control. The tablets were made by wet granulation method. Tablet produced were tested for the physical characterisation (uniformity of weight, and hardness, friability, and disintegration time tablet) and Dissolution test. The Dissolution test were done by using pedal method with Dissolution buffer of phosphate buffer pH 7,2 with spinning rate of 100 rpm in the temperature 37±0,5ºC for 60 minutes. The parameter used in this research is Dissolution Efficiency or DE30 (%). Data gained then analyzed statistically by using one way Analysis of Variance (ANOVA) and LSD (Least Significant Difference). The result showed the data have signifficant differences at the confidence of 95% The result of this study indicate that the addition of sodium lauryl sulfate had not effects on hardness, fragility and weight uniformity of tablets, but it has effect on the disintegration time. By adding more sodium lauryl sulfat, the disintegration time and the Dissolution rate were greater. The percentage of ketoprofen dissolved after 30th minute, for formula I, II, III and IV respectively were 14,64% ; 29,66% ; 32,06% ; 35,81%. Key words: sodium lauryl sulfate, tablet, ketoprofen, dissolutio
Arnaud Bouissonnie - One of the best experts on this subject based on the ideXlab platform.
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the Dissolution anisotropy of pyroxenes experimental validation of a stochastic Dissolution model based on enstatite Dissolution
Journal of Physical Chemistry C, 2020Co-Authors: Arnaud Bouissonnie, Damien Daval, Francois Guyot, Philippe AckererAbstract:The understanding of the atomic-scale mechanisms controlling silicate Dissolution represents a necessary prerequisite for the success of upscaling exercises aimed at predicting the rates of water–s...
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the Dissolution anisotropy of pyroxenes experimental validation of a stochastic Dissolution model based on enstatite Dissolution
Journal of Physical Chemistry C, 2020Co-Authors: Arnaud Bouissonnie, Damien Daval, Francois Guyot, Philippe AckererAbstract:The understanding of the atomic-scale mechanisms controlling silicate Dissolution represents a necessary prerequisite for the success of upscaling exercises aimed at predicting the rates of water-silicate interactions over large space and time scales. In that respect, it has been recently shown that physically-based stochastic models of crystal Dissolution at the atomic scale represent a promising alternative to the conventional treatment of silicate Dissolution rates, which consists in using empirical rate laws adjusted to the results of powder Dissolution experiments. However, most stochastic simulations conducted so far have been based on simple cubic solid structure, and very few were directed to ascertaining the extent to which the simulation outputs quantitatively compare to experimental measurements. In the present study, we take advantage of the anisotropic crystallographic structure and reactivity of chain silicates (pyroxenes) to tackle this issue. Face-specific enstatite Dissolution experiments...
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the Dissolution anisotropy of pyroxenes experimental validation of a stochastic Dissolution model based on enstatite Dissolution
The Journal of Physical Chemistry, 2020Co-Authors: Arnaud Bouissonnie, Damien Daval, Francois Guyot, Philippe AckererAbstract:The understanding of the atomic-scale mechanisms controlling silicate Dissolution represents a necessary prerequisite for the success of upscaling exercises aimed at predicting the rates of water–silicate interactions over large space and time scales. In that respect, it has been recently shown that physically based stochastic models of crystal Dissolution at the atomic scale represent a promising alternative to the conventional treatment of silicate Dissolution rates, which consists in using empirical rate laws adjusted to the results of powder Dissolution experiments. However, most stochastic simulations conducted so far have been based on simple cubic solid structure, and very few were directed to ascertaining the extent to which the simulation outputs quantitatively compare to experimental measurements. In the present study, we take advantage of the anisotropic crystallographic structure and reactivity of chain silicates (pyroxenes) to tackle this issue. Face-specific enstatite Dissolution experiments conducted at pH 0 and 90 °C reveal that the face-specific Dissolution rates observe the following trend: r⁽⁰⁰¹⁾ ≫ r⁽²¹⁰⁾ > r⁽⁰¹⁰⁾ ≥ r⁽¹⁰⁰⁾. Electron microscopy characterizations additionally show that lenticular etch pits elongated following the c axis grow on (hk0) faces, and that nanometer-thick amorphous Mg-depleted layers cover the reacted enstatite surfaces. A stochastic model was developed, and we show that simulations conducted with bond-breaking probability ratios (and therefore, activation energy differences) that are consistent with the existing literature regarding the hydrolysis of Mg–O–Mg, Mg–O–Si, and Si–O–Si bonds can quantitatively account for the measured Dissolution rates. In addition, the lenticular shape, the orientation, and the symmetry of the pits generated numerically on (hk0) faces are also consistent with those observed experimentally, while predicting the formation of Mg-depleted surface layers. As a consequence, this study provides a first milestone to the application of stochastic simulations to investigate the Dissolution of pyroxenes.
Siswanto Agus - One of the best experts on this subject based on the ideXlab platform.
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PENGARUH MEDIUM DISSOLUSI DAN PENGGUNAAN SINKER TERHADAP PROFIL DISOLUSI TABLET FLOATING ASPIRIN
'Lembaga Publikasi Ilmiah dan Penerbitan Universitas Muhammadiyah Purwokerto', 2014Co-Authors: Siswanto Agus, Fudholi Achmad, Nugroho, Akhmad Kharis, Martono SudibyoAbstract:ABSTRAK Disolusi merupakan faktor penting dalam pelepasan dan pengembangan sediaan obat. Selain sifat fisika kimia obat, formulasi, dan fabrikasi sediaan; kondisi uji disolusi juga mempengaruhi profil disolusi termasuk jenis medium dan model alat uji. Tujuan penelitian ini adalah untuk mengetahui pengaruh medium disolusi dan penggunaan sinker terhadap profil disolusi tablet floating aspirin. Tablet dibuat dengan metode cetak langsung dengan bahan tambahan Methocel K4M CR, NaHCO3, Ethocel, Aerosil, dan dikalsium fosfat anhidrat. Tablet diuji disolusi menggunakan alat disolusi USP apparatus 2 dengan pengaduk dayung. Medium disolusi yang digunakan yaitu simulated gastric fluid (SGF) tanpa pepsin pH 1,2 dan HCl 0,1 N. Uji disolusi dengan SGF tanpa pepsin pH 1,2 dilakukan dengan dan tanpa sinker. Suhu percobaan 37 ± 0,5 °C dan kecepatan pengadukan 60 rpm. Cairan sampel diambil pada menit ke-15, 30, 45, 60, 90, 120, 180, 240, 300, 360, 420, dan 480. Serapan sampel diukur dengan spektrofotometer UV pada λ 280 nm. Hasil uji disolusi menunjukkan bahwa perbedaan medium yaitu HCl 0,1 N dan SGF tidak mempengaruhi DE480, kinetika, dan mekanisme disolusi tablet floating aspirin. Penggunaan sinker pada medium SGF mempengaruhi DE480, kinetika, dan mekanisme disolusi. Kurva disolusi tablet floating aspirin pada medium HCl 0,1 N, SGF dengan dan tanpa sinker mengikuti kinetika orde I dan mekanisme disolusi menurut model Korsmeyer-Peppas, Weibull, Hopfenberg, dan Hixson-Crowell. Model Higuchi juga sesuai untuk profil disolusi tablet floating aspirin dalam medium SGF dengan sinker. Kata kunci: tablet floating aspirin, medium disolusi, sinker, profil disolusi ABSTRACK Dissolution is an important factor in the release and development of drug dosage form. In addition to physical and chemical properties of the drug, formulation, manufacturing process; the conditions of Dissolution test also affect the profile of Dissolution including the type of medium and test equipment models. The purpose of this study was to determine the influence of the Dissolution medium and the use of sinker on Dissolution profile of aspirin floating tablet. The tablets were made by direct compression method with Methocel K4M CR, NaHCO3, Ethocel, Aerosil, and dicalcium phosphate anhydrous as excipients. The in vitro Dissolution study was determined using USP apparatus 2 (paddle method), 900 mL Dissolution medium at 37 ± 0.2 °C and 60 rpm. The Dissolution test using HCl 0.1 N and simulated gastric fluid (SGF) pH 1.2 as medium with and without a sinker. Aliquouts of 5 mL was taken out at intervals of 15, 30, 45, 60, 120, 180, 240, 300, 360, 420, and 480 minutes. The samples were analyzed by UV-Vis spectrophotometer at 280 nm. The result indicated that the difference of medium (HCl 0.1 N and SGF pH 1.2) does not affect DE480, kinetics, and mechanism of Dissolution. The use of sinker in SGF affects DE480, kinetics, and mechanism of Dissolution. The profile of Dissolution of aspirin floating tablets in 0.1 N HCl and SGF pH 1.2 (with and without sinker) follow first-order kinetics and mechanism of Dissolution according to Korsmeyer-Peppas, Weibull, Hopfenberg, and Hixson-Crowell models. Higuchi model was also suitable for Dissolution profile of aspirin floating tablet in the SGF pH 1.2 with sinker. Keywords: floating tablet of aspirin, medium of Dissolution, sinker, profile of dissolutio
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PENGARUH PENAMBAHAN SODIUM LAURIL SULFAT (SLS) SEBAGAI SURFAKTAN TERHADAP SIFAT FISIK DAN UJI DISOLUSI TABLET KETOPROFEN
'Lembaga Publikasi Ilmiah dan Penerbitan Universitas Muhammadiyah Purwokerto', 2012Co-Authors: Pratama, Adithya Wahyu, Siswanto Agus, Suparman SuparmanAbstract:ABSTRAK Ketoprofen (asam 2-(3-benzoilfenil) propanoat) adalah turunan asam propionat dengan khasiat analgesic, antipiretik, dan antiinflamasi yang cukup baik namun mempunyai kelarutan yang praktis tidak larut dalam air. Penelitian ini bertujuan untuk meningkatkan kecepatan disolusi dan pengaruhnya terhadap sifat fisik tablet Ketoprofen menggunakan Sodium lauril sulfat sebagai surfaktan. Sodium lauril sulfat merupakan surfaktan yang dapat digunakan untuk meningkatkan pembasahan dan laju disolusi. Penelitian ini dilakukan dengan membuat empat formula tablet Ketoprofen dengan konsentrasi Sodium lauril sulfat yang berbeda (0%, 0,5%, 1%, dan 1,5%) sebagai bahan pembasah. Sebagai kontrol digunakan Ketoprofen tanpa penambahan Sodium lauril sulfat. Tablet dibuat dengan metode granulasi basah. Tablet yang dihasilkan diuji sifat fisik (keseragaman bobot, kekerasan, kerapuhan, dan waktu hancur tablet) dan uji disolusi. Uji disolusi dilakukan dengan metode dayung dengan medium disolusi dapar fosfat pH 7,2 dengan kecepatan putar 100 rpm pada suhu 37±0,5ºC selama 60 menit dan parameter uji disolusi yang dipakai adalah Dissolution Efficiency atau DE30 (%). Data yang diperoleh kemudian dianalisis secara statistik menggunakan Analisa Varian (ANOVA) satu jalan dan uji BNT (Beda Nyata Terkecil) pada data yang memiliki perbedaan bermakna dengan tingkat kepercayaan 95%. Hasil penelitian ini menunjukan bahwa penambahan sodium lauril sulfat tidak berpengaruh terhadap uji kekerasan tablet, uji kerapuhan dan uji keseragaman bobot tablet tapi berpengaruh terhadap uji waktu hancur yaitu semakin banyak sodium lauril sulfat yang ditambahkan semakin cepat pula waktu hancurnya, dan laju disolusi tablet semakin besar pula. Persentase ketoprofen terlarut pada menit ke-30 formula I, II, III, dan IV berturut-turut adalah 14,64% ; 29,66% ; 32,06% ; 35,81%. Kata kunci: sodium lauril sulfat, tablet, ketoprofen, disolusi. ABSTRACT Ketoprofen (acid 2-(3-benzoilfenil) propanoat) was derivated of propionat acid which has analgesic, antipyretic, and anti-inflammatory with poor solubillity in water. This research allowed to increase the Dissolution rate of ketoprofen tablets and effect on the physical characteristic by adding sodium lauril sulfat as surfactant. Sodium lauryl sulfat is a surfactant that can be used to improve wetting and Dissolution rate. This study was done with make four formula of ketoprofen tablets by different concentration of sodium lauryl sulfat (0%, 0,5%, 1%, and 1,5%) as a wetting agent. Ketoprofen without sodium lauryl sulfat was used as control. The tablets were made by wet granulation method. Tablet produced were tested for the physical characterisation (uniformity of weight, and hardness, friability, and disintegration time tablet) and Dissolution test. The Dissolution test were done by using pedal method with Dissolution buffer of phosphate buffer pH 7,2 with spinning rate of 100 rpm in the temperature 37±0,5ºC for 60 minutes. The parameter used in this research is Dissolution Efficiency or DE30 (%). Data gained then analyzed statistically by using one way Analysis of Variance (ANOVA) and LSD (Least Significant Difference). The result showed the data have signifficant differences at the confidence of 95% The result of this study indicate that the addition of sodium lauryl sulfate had not effects on hardness, fragility and weight uniformity of tablets, but it has effect on the disintegration time. By adding more sodium lauryl sulfat, the disintegration time and the Dissolution rate were greater. The percentage of ketoprofen dissolved after 30th minute, for formula I, II, III and IV respectively were 14,64% ; 29,66% ; 32,06% ; 35,81%. Key words: sodium lauryl sulfate, tablet, ketoprofen, dissolutio
