Search results

1

INVESTIGATION OF FENOFIBRATE DISSOLUTION RATE INCORPORATED ON SOLID DISPERSIONS INTO CHITOSAN

100%

Grimling B., Szcześniak M., Meler J., Pluta J.

Progress on Chemistry and Application of Chitin and its Derivatives

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2013

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vol. 18

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issue 18

149-156

EN

The aim of the study was to investigate the effect of chitosan on the dissolution of fenofibrate incorporated into this polymer carrier. The study investigated fenofibrate in physical mixtures at the drug to polymer ratio of 1:9, 3:7, and 5:5. The solubility investigation was performed by means of a dynamic method in a dissolution apparatus; mean amount of dissolved fenofibrate and the drug to polymer quantitative ratio in which the solid dispersion possessed the most beneficial properties improving the drug solubility were calculated. The study revealed a multi-fold increase (from 13 to 70 times) in fenofibrate solubility in the presence of chitosan, which increased with duration of the study and with increasing percentage of the polymer in formulations. The dissolution rates of fenofibrate in the presence of chitosan at the weight ratio 1:9 increased with the increment of the molecular weight of the chitosan. The obtained results may help develop new technologies for fenofibrate preparations with chitosan, with better solubility characteristics, and thus increased bioavailability of the drug.

2

CHARACTERISATION AND DISSOLUTION PROPERTIES OF KETOPROFEN IN BINARY SOLID DISPERSION WITH CHITOSAN

100%

Grimling B., Górniak A., Meler J., Szcześniak M.

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2014

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vol. 19

23-31

EN

BCS class II includes drugs with low solubility and high permeability. Ketoprofen is an example of this class of drugs. The aim of the study was to investigate the effect of chitosan with average molecular weights in various formulations on the dissolution of ketoprofen incorporated into this polymer carrier. The study investigated ketoprofen in solid dispersions using a method of the solvent evaporations at the drug to polymer ratios of 1:9. 3:7, and 5:5. The highest dissolution of fenofibrate, amounting to 98.8%, was observed after 60 minutes from solid dispersions with a drug-polymer weight ratio 1:9 in the presence of chitosan B and was 32-times higher in relation to the amount of added polymer in comparison to the solubility of pure drug. DSC and IR investigations showed that ketoprofen remained in its crystalline state in solid dispersion. There was no change in the chemical structure of the drug after the incorporation of the drug onto the polymer. Chitosan has been proposed as a useful excipient for enhancing the bioavailability of poorly water-soluble compounds.

3

Zero crossing and ratio spectra derivative spectrophotometry for the dissolution tests of amlodipine and perindopril in their fixed dose formulations

100%

Maczka P., Gumieniczek A., Galeza J., Pietras R.

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vol. 27

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issue 2

113-117

EN

Dissolution tests of amlodipine and perindopril from their fixed dose formulations were performed in 900 mL of phosphate buffer of pH 5.5 at 37°C using the paddle apparatus. Then, two simple and rapid derivative spectrophotometric methods were used for the quantitative measurements of amlodipine and perindopril. The first method was zero crossing first derivative spectrophotometry in which measuring of amplitudes at 253 nm for amlodipine and 229 nm for perindopril were used. The second method was ratio derivative spectrophotometry in which spectra of amlodipine over the linearity range were divided by one selected standard spectrum of perindopril and then amplitudes at 242 nm were measured. Similarly, spectra of perindopril were divided by one selected standard spectrum of amlodipine and then amplitudes at 298 nm were measured. Both of the methods were validated to meet official requirements and were demonstrated to be selective, precise and accurate. Since there is no official monograph for these drugs in binary formulations, the dissolution tests and quantification procedure presented here can be used as a quality control test for amlodipine and perindopril in respective dosage forms.

4

THE STUDY OF PHYSICOCHEMICAL PROPERTIES OF SOLID DISPERSIONS OF IBUPROFEN IN THE PRESENCE OF CHITOSAN

100%

Grimling B., Meler J., Szcześniak M., Pluta J., Górniak A.

Progress on Chemistry and Application of Chitin and its Derivatives

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2015

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vol. 20

64-72

EN

The aim of the present study was to increase the solubility of ibuprofen. Among the methods to increase the solubility selected solid dispersions of the drug with the polymer. Chitosan was used as the polymer. Solid dispersion obtained. Ibuprofen was incorporated into the chitosan type 652 with molar masse chitosan Mη = 429 kDa. Solid dispersions were prepared by using different ratios of ibuprofen and chitosan (1:9. 3:7 and 5:5). Formulations were tested dissolution rate of the ibuprofen. The highest dissolution of ibuprofen, amounting to 12.59%, was observed after 60 minutes from solid dispersion prepared by the evaporation method and 12.18% from physical mixtures with drug-polymer weight ratio 1:9 in the presence chitosan. The solubility of the drug improved more than 60-fold. XRPD analysis indicates the presence of the ibuprofen in amorphous form in the solid dispersion obtained by the modified solvent evaporation.

5

INVESTIGATION OF FENOFIBRATE SOLUBILITY IN THE PRESENCE OF CHITOSAN

100%

Grimling B., Meler J., Pluta J.

Progress on Chemistry and Application of Chitin and its Derivatives

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2012

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vol. 17

79 - 86

EN

Fenofibrate is an active substance which is well absorbed from the gastrointestinal tract, but it is characterized by limited solubility. Due to a wide spectrum of its pharmacological activity, it would be beneficial to improve its solubility, and thus increase the drug absorption capability. The aim of the study was to investigate the effect of chitosan on the solubility of fenofibrate incorporated into this polymer carrier. The study investigated fenofibrate in solid dispersions at the drug to polymer ratio of 3:7,5:5,7:3. The solubility investigation was performed by means of a dynamic method in a dissolution apparatus; mean amount of dissolved fenofibrate and the drug to polymer quantitative ratio in which the solid dispersion possessed the most beneficial properties improving the drug solubility were calculated. The study revealed a multi-fold increase (from 33 to 50 times) in fenofibrat solubility in the presence of chitosan, which increased with duration of the study and with increasing percentage of the polymer in formulations. The obtained results may help develop new technologies for fenofibrate preparations with chitosan, with better solubility characteristics, and thus increased bioavailability of the drug.

6

A multicarotenoid beadlet for human nutrition - proof of concept of in vitro timed release

100%

Gellenbeck K., Salter-Venzon D., Lala R., Chavan J.

Acta Biochimica Polonica

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2012

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vol. 59

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issue 1

35-38

EN

Since the 1980's when the predominate focus of study and use of carotenoids in human nutritional formulations was solely on beta-carotene, there has been a steady increase in research aimed to understand the role of a wide variety of carotenoids in human health. This work has increasingly demonstrated the benefits of a number of carotenoids, and there has been a corresponding increase in the number of carotenoids provided in nutritional supplements (multicarotenoids). Numerous published observations in both human and animal studies suggest significant interaction and competition between various carotenoids during absorption and metabolism, resulting in the inhibition of uptake of one over the other. This competition has the end result of reducing the beneficial effects of the inhibited carotenoid. To limit such competition and maximize carotenoid uptakes, a layered beadlet was designed to release a defined ratio of carotenoids sequentially. Preliminary dissolution testing is presented showing the release profile in simulated digestive conditions of a combination of beta-carotene, alpha carotene, lutein, zeaxanthin, lycopene and astaxanthin derived from natural sources. Comparison is made to an immediate release beadlet formulation using the same combination of carotenoids. These results will be used to guide proof of concept clinical testing for effectiveness in humans.

7

TECHNOLOGY OF PREPARATION AND EVALUATION OF KETOPROFEN-CHITOSAN SOLID DISPERSION

100%

Grimling B., Szcześniak M., Meler J., Pluta J.

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2014

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vol. 19

15-22

EN

The aim of the study was to investigate the effect of chitosan on the dissolution of ketoprofen incorporated into this polymer carrier. The study investigated ketoprofen in physical mixtures at the drug to polymer ratios of 1:9, 3:7, and 5:5. The solubility investigation was performed by means of a dynamic method in a dissolution apparatus; the mean amount of dissolved ketoprofen and the drug to polymer quantitative ratio in which the solid dispersion possessed the most beneficial properties improving the drug solubility were calculated. The study revealed a multifold increase (33 times) in ketoprofen solubility in the presence of chitosan, which increased with duration of the study and with increasing percentage of the polymer in formulations. The dissolution rates of ketoprofen in the presence of chitosan at the weight ratio 1:9 increased with the decrease of the molecular weight of the chitosan. The results obtained may help to develop new technologies for ketoprofen preparations with chitosan, with better solubility characteristics, and thus increased bioavailability of the drug.

8

EVALUATION OF PHYSICOCHEMICAL PROPERTIES OF SOLID DISPERSIONS OF BCS CLASS II SUBSTANCES WITH CHITOSAN

88%

Grimling B., Górniak A., Meler J., Pluta J.

Progress on Chemistry and Application of Chitin and its Derivatives

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2012

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vol. 17

87 - 94

EN

The BCS class II includes drugs with low solubility and high permeability. The substances require modification to increase their solubility in the upper part of the digestive system. Fenofibrate is an example of this class drugs. The aim of the study was to investigate the effect of chitosan on the solubility of fenofibrate incorporated into this polymer carrier. The study investigated fenofibrate in solid dispersions using a method of the solvent evaporation by means of freeze-drying at the drug to polymer ratio of 3:7,5:5,7:3. The study revealed a multi-fold increase (from 33 to 57 times) in fenofibrat solubility in the presence of chitosan, which increased with duration of the study and with increasing percentage of the polymer in formulations. DSC examination revealed a possible physical interaction between the drug and the polymer. The degree of lowering of temperature and increased heat effects is correlated with increased solubility of the drug in all the formulations. DSC studies confirmed that fenofibrate is present in solid dispersions in a crystalline form.

9

APPLICATION OF ION PAIR RP–HPLC METHOD IN PHARMACEUTICAL QUALITY CONTROL DISSOLUTION TESTING FOR SIMULTANEOUS ESTIMATION OF COMBINED TABLET DOSAGE FORMS WITH ACETYLSALICYLIC ACID AND GLYCINE

88%

Kowalska M. K., Wozniak M., Kijek M., Krawczyk M., Janas S.

Acta Poloniae Pharmaceutica - Drug Research

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2018

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vol. 75

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issue 3

EN

The aim of the paper was to present the possibility of applying the novel method (RP-HPLC ion pair method) for the simultaneous dissolution determination of combined tablet dosage form containing acetylsalicylic acid and glycine in pharmaceutical industry. The samples were gradient eluted using a Pursuit XS Ultra C18 column (150x3.0 mm, with a particle size of 2.8µm) with variable composition of mobile phase A (1-heptanesulfonic acid sodium salt aqueous solution (2.8 g/L), pH 2.2 ± 0.05 adjusted with orthophosphoric acid) and phase B (methanol). The detection was carried out at 210 nm with a consist flow rate of 0.4 mL min−1. The method was validated by determining precision (repeatability and intermediate precision), accuracy, specificity, linearity, range, system suitability, robustness and stability in accordance with ICH guidelines. The method was accurate, precise and linear within the range of 0.03 – 0.18 mg mL−1 for acetylsalicylic acid and 0.016 – 0.096 mg mL−1 for glycine. The method is simple, convenient and suitable for analyzing acetylsalicylic acid and glycine in pharmaceutical formulations. The method could also be used for routine assay determination after small modification of sample preparation.

10

Reprocessability of molybdenum and magnesia based inert matrix fuels

75%

Ebert E. L., Bukaemskiy A., Sadowski F., Lange S., Wilden A., Modolo G.

Nukleonika

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2015

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vol. 60

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issue 4

871-878

EN

This work focuses on the reprocessability of metallic 92Mo and ceramic MgO, which is under investigation for (Pu,MA)-oxide (MA = minor actinide) fuel within a metallic 92Mo matrix (CERMET) and a ceramic MgO matrix (CERCER). Magnesium oxide and molybdenum reference samples have been fabricated by powder metallurgy. The dissolution of the matrices was studied as a function of HNO3 concentration (1-7 mol/L) and temperature (25-90°C). The rate of dissolution of magnesium oxide and metallic molybdenum increased with temperature. While the MgO rate was independent of the acid concentration (1-7 mol/L), the rate of dissolution of Mo increased with acid concentration. However, the dissolution of Mo at high temperatures and nitric acid concentrations was accompanied by precipitation of MoO3. The extraction of uranium, americium, and europium in the presence of macro amounts of Mo and Mg was studied by three different extraction agents: tri-n-butylphosphate (TBP), N,Nʹ-dimethyl-N,Nʹ-dioctylhexylethoxymalonamide (DMDOHEMA), and N,N,N’,N’- -tetraoctyldiglycolamide (TODGA). With TBP no extraction of Mo and Mg occurred. Both matrix materials are partly extracted by DMDOHEMA. Magnesium is not extracted by TODGA (D < 0.1), but a weak extraction of Mo is observed at low Mo concentration.

11

The utilisation of fly ash in CO2 mineral carbonation

75%

Jaschik M., Jaschik J., Warmuziński K.

Chemical and Process Engineering

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2016

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vol. 37

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issue 1

12

Influence of zinc and magnesium substitution on ion release from Bioglass 45S5 at physiological and acidic pH

75%

Blochberger M., Hupa L., Brauer D. S.

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issue 1

EN

Ion release of Mg- and Zn-substituted Bioglass 45S5 (46.1 SiO2-2.6 P2O5-26.9 CaO-24.3Na2O; mol%; with 0, 25, 50, 75 or 100% of calcium replaced bymagnesium/zinc) was investigated at pH 7.4 (Tris buffer) and pH 4 (acetic acid/sodium acetate buffer) in static and dynamic dissolution experiments. Despite Mg2+ and Zn2+ having the same charge and comparable ionic radii, they influenced the dissolution behaviour in very different ways. In Tris, Mgsubstituted glasses showed similar ion release as 45S5, while Zn-substituted glasses showed negligible ion release. At low pH, however, release behaviour was similar, with all glasses releasing large percentages of ions within a few minutes. Precipitation of crystalline phases also varied, as Mg- and Zn-substitution inhibited apatite formation, and Zn-substitution resulted in formation of zinc phosphate phases at low pH. These results are relevant for glasses used in aluminium-free glass ionomer bone cements, as they show that Zn/Mg-substituted glasses release ions similarly fast as glasses containing no Zn/Mg, suggesting that these ions are no prerequisite for ionomer glasses. Zn-substituted glasses may potentially be used as controlled-release materials, which release antibacterial zinc ions when needed only, i.e. at low pH conditions (e.g. bacterial infection), but not at normal physiological pH conditions.

13

Benthic foraminifera from Pine Island and Ferrero bays, Amundsen Sea

75%

Majewski W.

Polish Polar Research

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2013

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issue 2

14

Hydrodynamika i naprężenia mechaniczne działające na postać leku w farmakopealnym i niekompendialnym badaniu uwalniania

63%

Wiater M., Hoc D., Paszkowska J., Garbacz G.

Farmacja Polska

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2020

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vol. 76

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issue 4

210-221

EN

The first and an essential step of medication’s path inside the human body is a dissolution of an active pharmaceutical ingridient. A dissolution of oral dosage forms occurs as a result of physicochemical and mechanical stresses which are found in gastrointestinal tract. This results in dissolution of the API, which becomes ready for the next step - absorption. In recent years, diversity and variability of digestive tract parameters has been understood better due to the advances in the research methods that allowed quantification of forces, mechanical stresses and pH gradients acting therein. Dissolution tests are conducted in order to determine the impact of biorelevant factors on the dosage form. These tests are a basic tool for the preclinical prediction of formulations behaviour in gastrointestinal tract, as well as for the quality control and to ensure formulations invariability after technological alterations in production. Pharmacopeia describes the standard procedure of dissolution tests. However, in the light of the research of actual conditions occurring in gastrointestinal tract the compendial methods appear to not fully reflect the hydrodynamic and mechanical stresses. This results in the lack of discriminatory power of pharmacopoeial dissolution tests, whereas differences between formulations occur in vivo. To face the need, simulators for the whole or partial gastrointestinal tract are constructed. These are advanced devices that enable the determination of the impact of the pH gradient, mechanical stresses and forces, enzymes secretion and many others, on the dosage form. The operation of a number of those simulators successfully predicts the behaviour of medication in vivo, which is an indispensable support during the formulation development. In the article there are described the mechanical and hydrodynamic gastrointestinal stresses, hydrodynamics of the most popular pharmacopoeial apparatus and non compendial gastrointestinal simulators, with regard to their ability to mimic biorelevant hydrodynamics.

PL

Dla doustnych postaci leku uwolnienie substancji czynnej zachodzi na skutek działania czynników fizykochemicznych i oddziaływań mechanicznych występujących w przewodzie pokarmowym człowieka. Różnorodność i zmienność parametrów organizmu ludzkiego została w ostatnich latach lepiej poznana dzięki zaawansowanym metodom badawczym, które pozwoliły na ilościowe opisanie sił i naprężeń mechanicznych występujących w przewodzie pokarmowym. Do poznania wpływu biorównoważnych czynników na postać leku prowadzi się badania uwalniania, które są podstawowym narzędziem do przedklinicznej prognozy zachowania się formulacji w przewodzie pokarmowym, ale też kontroli jakości produktu i weryfikacji wpływu zmian technologii produkcji na postać leku. Niestety w świetle odkryć dotyczących rzeczywistych warunków, występujących w przewodzie pokarmowym, metody kompendialne zdają się nie odzwierciedlać w pełni biorównoważnych czynników hydrodynamicznych i naprężeń mechanicznych. Jest to przyczyną, dla której wyniki tradycyjnych badań uwalniania często nie wykazują różnic pomiędzy formulacjami, które z kolei znacząco inaczej wypadają w badaniach in vivo. Aby umożliwić wykrycie różnic między formulacjami in vitro, konstruuje się symulatory całego przewodu pokarmowego, bądź wybranych jego aspektów. Są to zaawansowane urządzenia, pozwalające na badanie wpływu na postać leku takich czynników jak gradient pH, naprężenia i siły mechaniczne, dozowanie enzymów trawiennych i wiele innych. Działanie niektórych z tych aparatów pozwala na trafną predykcję zachowania leku w warunkach in vivo, co jest niezastąpioną pomocą podczas prac formulacyjnych. W niniejszym artykule przedstawiono mechaniczne i hydrodynamiczne warunki panujące w przewodzie pokarmowym, omówiono parametry hydrodynamiczne najpopularniejszych aparatów do uwalniania i przedstawiono modele przewodu pokarmowego, wybrane pod kątem realizacji biorównoważnych naprężeń mechanicznych i sił ścinających oraz zgniatających.

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INVESTIGATION OF FENOFIBRATE DISSOLUTION RATE INCORPORATED ON SOLID DISPERSIONS INTO CHITOSAN

CHARACTERISATION AND DISSOLUTION PROPERTIES OF KETOPROFEN IN BINARY SOLID DISPERSION WITH CHITOSAN

Zero crossing and ratio spectra derivative spectrophotometry for the dissolution tests of amlodipine and perindopril in their fixed dose formulations

THE STUDY OF PHYSICOCHEMICAL PROPERTIES OF SOLID DISPERSIONS OF IBUPROFEN IN THE PRESENCE OF CHITOSAN

INVESTIGATION OF FENOFIBRATE SOLUBILITY IN THE PRESENCE OF CHITOSAN

A multicarotenoid beadlet for human nutrition - proof of concept of in vitro timed release

TECHNOLOGY OF PREPARATION AND EVALUATION OF KETOPROFEN-CHITOSAN SOLID DISPERSION

EVALUATION OF PHYSICOCHEMICAL PROPERTIES OF SOLID DISPERSIONS OF BCS CLASS II SUBSTANCES WITH CHITOSAN

APPLICATION OF ION PAIR RP–HPLC METHOD IN PHARMACEUTICAL QUALITY CONTROL DISSOLUTION TESTING FOR SIMULTANEOUS ESTIMATION OF COMBINED TABLET DOSAGE FORMS WITH ACETYLSALICYLIC ACID AND GLYCINE

Reprocessability of molybdenum and magnesia based inert matrix fuels

The utilisation of fly ash in CO2 mineral carbonation

Influence of zinc and magnesium substitution on ion release from Bioglass 45S5 at physiological and acidic pH

Benthic foraminifera from Pine Island and Ferrero bays, Amundsen Sea

Hydrodynamika i naprężenia mechaniczne działające na postać leku w farmakopealnym i niekompendialnym badaniu uwalniania