@article{MTMT:3119939,
	title = {Influence of barium sulfate X-ray imaging contrast material on properties of floating drug delivery tablets.},
	url = {https://m2.mtmt.hu/api/publication/3119939},
	author = {Diós, Péter and Szigeti, Krisztián and Budán, Ferenc Csaba and Pocsik, M and Veres, Dániel and Máthé, Domokos and Pál, Szilárd and Dévay, Attila and Nagy, Sándor},
	doi = {10.1016/j.ejps.2016.09.034},
	journal-iso = {EUR J PHARM SCI},
	journal = {EUROPEAN JOURNAL OF PHARMACEUTICAL SCIENCES},
	volume = {95},
	unique-id = {3119939},
	issn = {0928-0987},
	abstract = {The objective of the study was to reveal the influence of necessarily added barium sulfate (BaSO4) X-ray contrast material on floating drug delivery tablets. Based on literature survey, a chosen floating tablet composition was determined containing HPMC and carbopol 943P as matrix polymers. One-factor factorial design with five levels was created for evaluation of BaSO4 (X1) effects on experimental parameters of tablets including: floating lag time, total floating time, swelling-, erosion-, dissolution-, release kinetics parameters and X-ray detected volume changes of tablets. Applied concentrations of BaSO4 were between 0 and 20.0% resulting in remarkable alteration of experimental parameters related especially to flotation. Drastic deterioration of floating lag time and total floating time could be observed above 15.0% BaSO4. Furthermore, BaSO4 showed to increase the integrity of tablet matrix by reducing eroding properties. A novel evaluation of dissolutions from floating drug delivery systems was introduced, which could assess the quantity of drug dissolved from dosage form in floating state. In the cases of tablets containing 20.0% BaSO4, only the 40% of total API amount could be dissolved in floating state. In vitro fine resolution X-ray CT imagings were performed to study the volume change and the voxel distributions as a function of HU attenuations by histogram analysis of the images. X-ray detected relative volume change results did not show significant difference between samples. After 24h, all tablets containing BaSO4 could be segmented, which highlighted the fact that enough BaSO4 remained in the tablets for their identification.},
	year = {2016},
	eissn = {1879-0720},
	pages = {46-53},
	orcid-numbers = {Veres, Dániel/0000-0002-9687-3556}
}

@mastersthesis{MTMT:3071247,
	title = {Preformulation studies and optimization of floating drug delivery systems based on pharmaceutical technological and biopharmaceutical parameters. Design of modified drug delivery systems},
	url = {https://m2.mtmt.hu/api/publication/3071247},
	author = {Diós, Péter},
	publisher = {PTE},
	unique-id = {3071247},
	year = {2016}
}

@article{MTMT:3033954,
	title = {X-Ray CT Imaging of Stomach Passage of Contrast-Enhanced Floating Tablets in a New Rat Model},
	url = {https://m2.mtmt.hu/api/publication/3033954},
	author = {Máthé, Domokos and Budan, F and Pál, Szilárd and Kiss, I and Diós, Péter and Szigeti, Krisztián},
	journal-iso = {EUR J NUCL MED MOL I},
	journal = {EUROPEAN JOURNAL OF NUCLEAR MEDICINE AND MOLECULAR IMAGING},
	volume = {42},
	unique-id = {3033954},
	issn = {1619-7070},
	year = {2015},
	eissn = {1619-7089},
	pages = {S412-S413}
}

@misc{MTMT:3025450,
	title = {X-Ray CT Imaging of Stomach Passage of Contrast-Enhanced Floating Tablets in a New Rat Model},
	url = {https://m2.mtmt.hu/api/publication/3025450},
	author = {Máthé, Domokos and Budán, Ferenc and Pál, Szilárd and Kiss, István and Diós, Péter and Szigeti, Krisztián},
	unique-id = {3025450},
	abstract = {Introduction. Cost-effective in vivo animal models are 
		warranted to be developed to test modified drug delivery 
		systems with the purpose to optimize those medical agent 
		carriers. In this study, a novel rat model was evaluated to 
		gain information about attributions of floating drug delivery 
		systems (FDDS) practically in form of small sized tablets. X-
		ray computed tomography (CT) was performed.Materials and 
		Methods. Sodium alginate as a biodegradable swelling polymer 
		to create coherent frame of the tablets, sodium bicarbonate 
		as carbon dioxide (CO2) creating agent and barium sulfate 
		(BaSO4) contrast material to enhance X-ray CT. Partly 
		anaesthetized rats were made to swallow tablets. In vivo 
		imaging was performed at the following sampling times: 15 
		min, 1 h, 2 h, 3 h, 4 h, 6 h, 24 h and 48 h. Additionally, a 
		maximum intensity projection (MIP) was rendered at 30 min 
		after administration to provide fine resolution of spatial 
		and temporal details about FDDSs in situ behavior using an 
		adequate selected lookup table (LUT).Results. tablets with 
		10% BaSO4 content enabled quantitative in vivo imaging. These 
		pharmaceutical agent carriers formed CO2 bubbles 15 minutes 
		after the administration and remained floating in the stomach 
		for at least 24 hours. 48 hours after administration tablets 
		were observed to be disintegrated mostly in the small 
		intestine. Thus, the tablet?s putative obstruction in stomach 
		can be excluded. So the model can be considered as cheap, 
		representative and capable to interpret results 
		better.Conclusions.We can suppose that this newly developed 
		rat model will be useful to provide comprehensive data about 
		certain factors (e.g. food effect, posture, etc.) influencing 
		gastrointestinal behavior of FDDS in future experiments by 
		tracking their properties.},
	year = {2015}
}

@misc{MTMT:3025443,
	title = {Parameters of floating drug delivery systems - tracked in animal model utilizing in vivo X-ray CT imaging},
	url = {https://m2.mtmt.hu/api/publication/3025443},
	author = {Diós, Péter and Budán, Ferenc and Szigeti, Krisztián and Horváth, Ildikó and Nagy, Sándor and Pernecker, Tivadar and Dévay, Attila and Gerencsér, Gellért and Gyöngyi, Zoltán and Kiss, István and Pál, Szilárd and Máthé, Domokos},
	unique-id = {3025443},
	abstract = {Attribution of floating drug delivery systems (FDDSs) can be 
		studied utilizing in vivo animal models recently including X-
		ray imaging. High resolution X-ray computed tomography (CT) 
		(1) approach could be cost-effective in respect to the 
		information possessed in comparison to costs. Comprehensive 
		data can be provided about specific factors (e.g. quantity of 
		distinct excipients, food effect, anaesthetics, posture) 
		influencing gastrointestinal behavior of specific tested drug 
		delivery systems (2).
		In this study, a novel in vivo Wistar rat model was evaluated 
		to gain information about spatial and temporal patterns of 
		structure, position and behavior of floating drug delivery 
		systems, practically in form of small sized tablets. 
		Different concentrations (5, 10 and 20%) of barium sulfate 
		contrast material enhanced X-ray imaging. For in vivo X-ray 
		CT evaluation, suitable concentration of barium sulfate was 
		determined. Flotation of tablets could be achieved for 24 
		hours in stomach and after 48 hours tablets were present in 
		the intestinal system. During the examination, structural 
		changes of floating tablets could be tracked such as 
		disintegration or swelling.},
	year = {2015}
}

@misc{MTMT:3025435,
	title = {Achievement of very high floating force and rapid dissolution of sodium alginate based floating drug delivery systems: in vitro, in vivo study},
	url = {https://m2.mtmt.hu/api/publication/3025435},
	author = {Diós, Péter and Budán, Ferenc and Nagy, Sándor and Horváth, Ildikó and Szigeti, Krisztián and Máthé, Domokos and Pál, Szilárd and Dévay, Attila},
	unique-id = {3025435},
	abstract = {Floating force values as examination parameters have one of 
		the most significant influence on the buoyancy of floating 
		drug delivery systems (FDDSs) beyond floating lag time and 
		total floating time (1-3). Gastric retention and consequently 
		location of drug release may be significantly affected by how 
		FDDSs float, however in most of the cases floating force 
		values are not measured.
		The aim of this study is to examine sodium alginate (X1), 
		low-substituted hydroxypropyl cellulose (L-HPC B1, X2), and 
		sodium bicarbonate (X3) concentrations in floating tablets to 
		achieve very high value of floating force. Face-centered 
		central composite design was used with three numerical 
		factors in three levels. X1 and X2 were used in unusual 
		concentration intervals: sodium alginate in 2.5-5% and L-HPC 
		B1 40-50%.
		Studied examination parameters were: floating lag time 
		(tlag), maximal floating force (Fmax), and time for maximal 
		floating force (tFmax), dissolution. Formulation with the 
		highest floating force was studied in vivo using X-ray CT for 
		24 hours. Result showed very high values of maximal floating 
		force at several formulation. Optimal tablets for our further 
		fine-optimization aims were studied in rats, where 24 hours 
		of gastric retention was observed.},
	year = {2015}
}

@misc{MTMT:3025432,
	title = {Influence of sodium alginate and low-substituted hydroxylpropyl cellulose quantity in floating behavior and drug release in floating drug delivery systems},
	url = {https://m2.mtmt.hu/api/publication/3025432},
	author = {Diós, Péter and Nagy, Sándor and Pernecker, Tivadar and Pál, Szilárd and Dévay, Attila},
	unique-id = {3025432},
	abstract = {The aim of this research is to evaluate the influence of low-
		substituted hydroxypropyl cellulose (L-HPC) and sodium 
		alginate concentrations on floating behavior and drug release 
		of floating drug delivery systems. Face-centered central 
		composite design was used with two numerical factors (sodium 
		alginate %, X1; L-HPC B1 %, X2) and three levels. Sodium 
		alginate amount between 0.5% and 35.15%, L-HPC amount between 
		0.5 and 25% were used (1).
		Studied parameters (dependent variables) were the following: 
		floating lag time (tlag), maximal floating forces (Fmax) and 
		dissolution of paracetamol.
		On floating lag time data, only sodium alginate was 
		significant factor, while both factors and their interactions 
		were significant in the case of maximal floating force. 
		Significance of factors on dissolution data was depended on 
		the sampling time.
		Results of floating lag time, floating force and paracetamol 
		release studies revealed various behavior of floating tablets 
		depending on L-HPC and sodium alginate quantity. Low level of 
		sodium alginate (0.5%) resulted in shorter floating lag times 
		and rapid dissolution in comparison with the other 
		formulations. Results highlight the possible wide range 
		applicability of sodium alginate as swelling polymer and L-
		HPC as disintegrant.},
	year = {2015}
}

@CONFERENCE{MTMT:2929738,
	title = {Hidrofil mátrixképző polimerek alkalmazhatósága efferveszcens úszó készítményekben},
	url = {https://m2.mtmt.hu/api/publication/2929738},
	author = {Diós, Péter and Nagy, Sándor and Bognár, Vivien and Pál, Szilárd and Dévay, Attila},
	booktitle = {I. Cholnoky László Szakkollégiumi Szimpózium},
	unique-id = {2929738},
	abstract = {Módosított hatóanyag-leadású készítmények alapos 
		megtervezésével különböző biofarmáciai igényeknek 
		megfelelő hatóanyag-felszabadulású rendszerek készíthetők. 
		Ezen készítmények előállítása során a 
		hatóanyag-leadás módosítását speciális segédanyagok és/vagy 
		különleges technológiai eljárások 
		segítségével érhetjük el. A gasztroretentív rendszerek 
		alkalmazásának célja a készítmények gyomorban 
		való tartózkodási idejének meghosszabbítása.
		A gasztroretentív rendszerek leggyakrabban alkalmazott 
		technológiai megvalósítása az úszó hatóanyag-
		leadó rendszerek (FDDSs). Ezen úszó rendszerek gyomor 
		retenciós idejének megnövelését azok lecsökkent 
		átlagsűrűsége révén érhető el. A szakirodalom az úszó 
		készítményeken belül élesen elkülöníti az 
		efferveszcens és nem-efferveszcens úszó rendszereket. 
		Az előadás célja, hogy bemutassa a gyógyszertechnológiai 
		gyakorlatban, az iparban és magisztrálisan 
		egyaránt leggyakrabban használt hét hidrofil mátrixképző 
		polimer efferveszcens úszótablettákban való 
		alkalmazhatóságát. Az elkészített tabletták összetételei csak 
		az alkalmazott polimerekben különböznek. 
		Alkalmazott hidrofil mátrixképzők: hidroxipropil-
		metilcellulóz (HPMC), metilcellulóz (MC), hidroxietil-
		cellulóz (HEC), karmellóz-nátrium (CMC-Na), kismértékben 
		szubsztituált hidroxipropilcellulóz (L-HPC), 
		nátrium-alginát, karbomer (Carbopol 934P).
		A kísérlet során elvégzett vizsgálatok: az úszás eléréséhez 
		szükséges idő (tlag) meghatározása és a 
		hatóanyag 24 órás kioldódás vizsgálata.
		A vizsgálati minták eredményei között jelentős különbségek 
		mutatkoztak. Egyes minták teljes 
		hatóanyagtartalma 24 órás vizsgálat során sem tudott 
		felszabadulni, míg több esetben már akár egy órát 
		követően teljes hatóanyag kioldódás és gyors duzzadás volt 
		tapasztalható.},
	year = {2015},
	pages = {x}
}

@article{MTMT:2924040,
	title = {Preformulation studies and optimization of sodium alginate based floating drug delivery system for eradication of Helicobacter pylori},
	url = {https://m2.mtmt.hu/api/publication/2924040},
	author = {Diós, Péter and Nagy, Sándor and Pál, Szilárd and Pernecker, Tivadar and Kocsis, Béla and Budán, Ferenc Csaba and Horváth, Ildikó and Szigeti, Krisztián and Bölcskei, Kata and Máthé, Domokos and Dévay, Attila},
	doi = {10.1016/j.ejpb.2015.07.020},
	journal-iso = {EUR J PHARM BIOPHARM},
	journal = {EUROPEAN JOURNAL OF PHARMACEUTICS AND BIOPHARMACEUTICS},
	volume = {96},
	unique-id = {2924040},
	issn = {0939-6411},
	abstract = {The aim of this study was to design a local, floating, mucoadhesive drug delivery system containing metronidazole for Helicobacter pylori eradication. Face-centered central composite design (with three factors, in three levels) was used for evaluation and optimization of in vitro floating and dissolution studies. Sodium alginate (X1), low substituted hydroxypropyl cellulose (L-HPC B1, X2) and sodium bicarbonate (X3) concentrations were the independent variables in the development of effervescent floating tablets. All tablets showed acceptable physicochemical properties. Statistical analysis revealed that tablets with 5.00 % sodium alginate, 38.63 % L-HPC B1 and 8.45 % sodium bicarbonate content showed promising in vitro floating and dissolution properties for further examinations. Optimized floating tablets expressed remarkable floating force. Their in vitro dissolution studies were compared with two commercially available non-floating metronidazole products and then microbiologically detected dissolution, ex vivo detachment force, rheological mucoadhesion studies and compatibility studies were carried out. Remarkable similarity (f1, f2) between in vitro spectrophotometrically and microbiologically detected dissolutions was found. Studies revealed significant ex vivo mucoadhesion of optimized tablets, which was considerably increased by L-HPC. In vivo X-ray CT studies of optimized tablets showed 8 h gastroretention in rats represented by an animation prepared by special CT technique.},
	year = {2015},
	eissn = {1873-3441},
	pages = {196-206}
}

@article{MTMT:2807473,
	title = {Influence of different types of low substituted hydroxypropyl cellulose on tableting, disintegration, and floating behaviour of floating drug delivery systems},
	url = {https://m2.mtmt.hu/api/publication/2807473},
	author = {Diós, Péter and Pernecker, Tivadar and Nagy, Sándor and Pál, Szilárd and Dévay, Attila},
	doi = {10.1016/j.jsps.2014.09.001},
	journal-iso = {SAUDI PHARM J},
	journal = {SAUDI PHARMACEUTICAL JOURNAL},
	volume = {23},
	unique-id = {2807473},
	issn = {1319-0164},
	abstract = {Abstract The object of the present study is to evaluate the effect of application of low-substituted hydroxypropyl cellulose (L-HPC) 11 and B1 as excipients promoting floating in gastroretentive tablets. Directly compressed tablets were formed based on experimental design. Face-centred central composite design was applied with two factors and 3 levels, where amount of sodium alginate (X1) and L-HPC (X2) were the numerical factors. Applied types of L-HPCs and their 1:1 mixture were included in a categorical factor (X3). Studied parameters were floating lag time, floating time, floating force, swelling behaviour of tablets and dissolution of paracetamol, which was used as a model active substance. Due to their physical character, L-HPCs had different water uptake and flowability. Lower flowability was observed and lower water uptake after 60 minutes at L-HPC 11 compared to L-HPC B1. Shorter floating times were detected at L-HPC 11 and L-HPC mixtures with 0.5% content of sodium alginate, whereas alginate was the only significant factor. Evaluating results of drug release and swelling studies on floating tablets revealed correlation, which can serve to help to understand the mechanism of action of L-HPCs in the field development of gastroretentive dosage forms.},
	keywords = {DISINTEGRATION; Sodium alginate; Floating force; Gastroretentive; Floating tablets; Low substituted hydroxypropyl cellulose},
	year = {2015},
	eissn = {2213-7475},
	pages = {658-666}
}