Pepić, Dragana

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47636530-9161-48aa-b342-a70b2b06924b
  • Pepić, Dragana (6)
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Author's Bibliography

Release behaviour of carbamazepine-loaded poly(epsilon-caprolactone)/poly(ethylene oxide) microspheres

Pepić, Dragana; Nikolić, Marija; Grujić, Svetlana; Laušević, Mila; Đonlagić, Jasna

(Informa Healthcare, London, 2013)

TY  - JOUR
AU  - Pepić, Dragana
AU  - Nikolić, Marija
AU  - Grujić, Svetlana
AU  - Laušević, Mila
AU  - Đonlagić, Jasna
PY  - 2013
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/2475
AB  - Poly(epsilon-caprolactone) (PCL), a biodegradable and biocompatible aliphatic polyester has a great potential as a drug carrying material in controlled drug delivery/release systems. The most simple and economical way to tailor the release profile of active substances from biodegradable polymer matrix is by the addition of the second polymeric component in the polymer matrix, i.e. by blending. This study describes the preparation and characterization of a carbamazepine-loaded microspheres by the use of PCL blended with poly(ethylene oxide) as a drug carrying material. By the use of two-component hydrophilic/hydrophobic polymer blend as a microspheres' matrix material, release profile of the drug can be modified and dictated. The microspheres prepared by classical oil-in-water emulsion solvent evaporation technique were characterized with respect to particle size and morphology, polymer matrix composition, encapsulation efficiency, physical state of the drug and in vitro release behaviour. It was presented that the release profile can be modified by the presence and the amount of hydrophilic component in the starting formulation of microspheres.
PB  - Informa Healthcare, London
T2  - Journal of Microencapsulation
T1  - Release behaviour of carbamazepine-loaded poly(epsilon-caprolactone)/poly(ethylene oxide) microspheres
EP  - 160
IS  - 2
SP  - 151
VL  - 30
DO  - 10.3109/02652048.2012.704954
ER  - 
@article{
author = "Pepić, Dragana and Nikolić, Marija and Grujić, Svetlana and Laušević, Mila and Đonlagić, Jasna",
year = "2013",
abstract = "Poly(epsilon-caprolactone) (PCL), a biodegradable and biocompatible aliphatic polyester has a great potential as a drug carrying material in controlled drug delivery/release systems. The most simple and economical way to tailor the release profile of active substances from biodegradable polymer matrix is by the addition of the second polymeric component in the polymer matrix, i.e. by blending. This study describes the preparation and characterization of a carbamazepine-loaded microspheres by the use of PCL blended with poly(ethylene oxide) as a drug carrying material. By the use of two-component hydrophilic/hydrophobic polymer blend as a microspheres' matrix material, release profile of the drug can be modified and dictated. The microspheres prepared by classical oil-in-water emulsion solvent evaporation technique were characterized with respect to particle size and morphology, polymer matrix composition, encapsulation efficiency, physical state of the drug and in vitro release behaviour. It was presented that the release profile can be modified by the presence and the amount of hydrophilic component in the starting formulation of microspheres.",
publisher = "Informa Healthcare, London",
journal = "Journal of Microencapsulation",
title = "Release behaviour of carbamazepine-loaded poly(epsilon-caprolactone)/poly(ethylene oxide) microspheres",
pages = "160-151",
number = "2",
volume = "30",
doi = "10.3109/02652048.2012.704954"
}
Pepić, D., Nikolić, M., Grujić, S., Laušević, M.,& Đonlagić, J.. (2013). Release behaviour of carbamazepine-loaded poly(epsilon-caprolactone)/poly(ethylene oxide) microspheres. in Journal of Microencapsulation
Informa Healthcare, London., 30(2), 151-160.
https://doi.org/10.3109/02652048.2012.704954
Pepić D, Nikolić M, Grujić S, Laušević M, Đonlagić J. Release behaviour of carbamazepine-loaded poly(epsilon-caprolactone)/poly(ethylene oxide) microspheres. in Journal of Microencapsulation. 2013;30(2):151-160.
doi:10.3109/02652048.2012.704954 .
Pepić, Dragana, Nikolić, Marija, Grujić, Svetlana, Laušević, Mila, Đonlagić, Jasna, "Release behaviour of carbamazepine-loaded poly(epsilon-caprolactone)/poly(ethylene oxide) microspheres" in Journal of Microencapsulation, 30, no. 2 (2013):151-160,
https://doi.org/10.3109/02652048.2012.704954 . .
16
11
15

Optimization of preparation conditions of poly(ε-caprolactone) microspheres for controlled release of carbamazepine

Pepić, Dragana; Anđelković, Darinka R.; Nikolić, Marija; Grujić, Svetlana; Đonlagić, Jasna

(Association of Chemical Engineers of Serbia, 2010)

TY  - JOUR
AU  - Pepić, Dragana
AU  - Anđelković, Darinka R.
AU  - Nikolić, Marija
AU  - Grujić, Svetlana
AU  - Đonlagić, Jasna
PY  - 2010
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/1656
AB  - Poly (ε-caprolactone), PCL, is an aliphatic polyester suitable for controlled drug release due to its biodegradability, biocompatibility, non-toxicity and high permeability to many therapeutic drugs. This study investigates the effect of the preparation parameters on the size and the morphology of the PCL microspheres and on the release profile of carbamazepine from these microspheres. The PCL microspheres were prepared using oil-in-water (o/w) emulsion solvent evaporation method with the poly(vinyl alcohol), PVA, as the emulsion stabilizer. The influence of the stirring rate applied during the emulsion formation, the homogenization time and the emulsifier concentration on diameter and size distribution of the microspheres was analyzed by scanning electron microscope (SEM). The initial emulsion was formed applying high stirring rates of 10000, 18000 and 23000 rpm, for homogenization times: 5, 10 and 15 min. The diameter was strongly influenced by the stirring rate, and the average particle size decreased from 9.2 to 2.8 ìm with the increase of the stirring rate. Increasing the amount of PVA in the water phase from 0.2 to 1 mass% improved stabilization of the oil droplets and led to a slight decrease of the average particle diameter. Drug-loaded microspheres were prepared by the same technique using different amounts of carbamazepine (10 and 15 mass%), under given conditions (1.0 mass% PVA, stirring rate of 18000 rpm for a period of 5 min of emulsion formation). Additionally, microspheres were prepared by applying low stirring rate of 1000 rpm with 10 and 15 mass% of the drug. The SEM analysis showed that microspheres created with 18000 rpm stirring rate, had average diameters of 3-4 ìm, and the microspheres prepared with 1000 rpm stirring rate were larger than 100 ìm. It was also observed that, in the case of the large microspheres, carbamazepine was deposited on their surfaces, while the small microspheres had smooth surfaces without observable drug crystals. The encapsulation efficiency and the release behaviour of the carbamazepine were examined using high performance liquid chromatography-ultraviolet spectroscopy (HPLC-UV). The drug encapsulation efficiencies were in the range from 69 to 81%, and were increasing with the increase of the amount of carbamazepine in both series. In vitro release experiments were carried out in the phosphate buffer solution (pH 7) at 37°C. The release rate was influenced by the microspheres size and morphology. The larger microspheres released more carbamazepine (85-95%) compared to the small ones (50-65%) for the same period. This behavior was attributed to the different drug distribution in the PCL matrix. Different mathematical models were used to describe drug release kinetics. It was concluded that the mechanism of the carbamazepine release from the microspheres was diffusion-controlled, independent on the type of microspheres. The kinetic parameters showed that the release of carbamazepine was slower from the smaller microspheres, probably as a result of more even distribution of the drug in the polymer matrix.
AB  - Cilj ovog rada je ispitivanje uticaja uslova dobijanja mikrosfera biodegradabilnog poli(ε-kaprolaktona) tehnikom otparavanja rastvarača iz emulzije, na veličinu i raspodelu veličina mikrosfera. Polazne emulzije rastvora polimera u vodi formirane su pri velikim brzinama mešanja tokom formiranja emulzije u opsegu od 10000 do 23000 o min-1, radi dobijanja mikrosfera malih prečnika. Varirana je brzina mešanja prilikom formiranja emulzije, dužina trajanja emulgovanja velikim brzinama mešanja i udeo stabilizatora emulzije, poli(vinil alkohola). Veličina i raspodela veličina polimernih mikrosfera određivana je skenirajućom elektronskom mikroskopijom. U polimerne mikrosfere inkapsuliran je lek karbamazepin iz grupe antiepileptika i određivana je efikasnost inkapsulacije, kao i profil otpuštanja leka u puferskom rastvoru metodom tečne hromatografije sa UV spektroskopijom. Takođe je izučavana kinetika otpuštanja karbamazepina korišćenjem različitih modela s ciljem ispitivanja mehanizma otpuštanja leka iz mikrosfera dobijenih pri različitim uslovima.
PB  - Association of Chemical Engineers of Serbia
T2  - Hemijska industrija
T1  - Optimization of preparation conditions of poly(ε-caprolactone) microspheres for controlled release of carbamazepine
T1  - Optimizacija uslova dobijanja mikrosfera na bazi biodegradabilnog poli(ε-kaprolaktona) za kontrolisano otpuštanje karbamazepina
EP  - 502
IS  - 6
SP  - 491
VL  - 64
DO  - 10.2298/HEMIND101117073P
ER  - 
@article{
author = "Pepić, Dragana and Anđelković, Darinka R. and Nikolić, Marija and Grujić, Svetlana and Đonlagić, Jasna",
year = "2010",
abstract = "Poly (ε-caprolactone), PCL, is an aliphatic polyester suitable for controlled drug release due to its biodegradability, biocompatibility, non-toxicity and high permeability to many therapeutic drugs. This study investigates the effect of the preparation parameters on the size and the morphology of the PCL microspheres and on the release profile of carbamazepine from these microspheres. The PCL microspheres were prepared using oil-in-water (o/w) emulsion solvent evaporation method with the poly(vinyl alcohol), PVA, as the emulsion stabilizer. The influence of the stirring rate applied during the emulsion formation, the homogenization time and the emulsifier concentration on diameter and size distribution of the microspheres was analyzed by scanning electron microscope (SEM). The initial emulsion was formed applying high stirring rates of 10000, 18000 and 23000 rpm, for homogenization times: 5, 10 and 15 min. The diameter was strongly influenced by the stirring rate, and the average particle size decreased from 9.2 to 2.8 ìm with the increase of the stirring rate. Increasing the amount of PVA in the water phase from 0.2 to 1 mass% improved stabilization of the oil droplets and led to a slight decrease of the average particle diameter. Drug-loaded microspheres were prepared by the same technique using different amounts of carbamazepine (10 and 15 mass%), under given conditions (1.0 mass% PVA, stirring rate of 18000 rpm for a period of 5 min of emulsion formation). Additionally, microspheres were prepared by applying low stirring rate of 1000 rpm with 10 and 15 mass% of the drug. The SEM analysis showed that microspheres created with 18000 rpm stirring rate, had average diameters of 3-4 ìm, and the microspheres prepared with 1000 rpm stirring rate were larger than 100 ìm. It was also observed that, in the case of the large microspheres, carbamazepine was deposited on their surfaces, while the small microspheres had smooth surfaces without observable drug crystals. The encapsulation efficiency and the release behaviour of the carbamazepine were examined using high performance liquid chromatography-ultraviolet spectroscopy (HPLC-UV). The drug encapsulation efficiencies were in the range from 69 to 81%, and were increasing with the increase of the amount of carbamazepine in both series. In vitro release experiments were carried out in the phosphate buffer solution (pH 7) at 37°C. The release rate was influenced by the microspheres size and morphology. The larger microspheres released more carbamazepine (85-95%) compared to the small ones (50-65%) for the same period. This behavior was attributed to the different drug distribution in the PCL matrix. Different mathematical models were used to describe drug release kinetics. It was concluded that the mechanism of the carbamazepine release from the microspheres was diffusion-controlled, independent on the type of microspheres. The kinetic parameters showed that the release of carbamazepine was slower from the smaller microspheres, probably as a result of more even distribution of the drug in the polymer matrix., Cilj ovog rada je ispitivanje uticaja uslova dobijanja mikrosfera biodegradabilnog poli(ε-kaprolaktona) tehnikom otparavanja rastvarača iz emulzije, na veličinu i raspodelu veličina mikrosfera. Polazne emulzije rastvora polimera u vodi formirane su pri velikim brzinama mešanja tokom formiranja emulzije u opsegu od 10000 do 23000 o min-1, radi dobijanja mikrosfera malih prečnika. Varirana je brzina mešanja prilikom formiranja emulzije, dužina trajanja emulgovanja velikim brzinama mešanja i udeo stabilizatora emulzije, poli(vinil alkohola). Veličina i raspodela veličina polimernih mikrosfera određivana je skenirajućom elektronskom mikroskopijom. U polimerne mikrosfere inkapsuliran je lek karbamazepin iz grupe antiepileptika i određivana je efikasnost inkapsulacije, kao i profil otpuštanja leka u puferskom rastvoru metodom tečne hromatografije sa UV spektroskopijom. Takođe je izučavana kinetika otpuštanja karbamazepina korišćenjem različitih modela s ciljem ispitivanja mehanizma otpuštanja leka iz mikrosfera dobijenih pri različitim uslovima.",
publisher = "Association of Chemical Engineers of Serbia",
journal = "Hemijska industrija",
title = "Optimization of preparation conditions of poly(ε-caprolactone) microspheres for controlled release of carbamazepine, Optimizacija uslova dobijanja mikrosfera na bazi biodegradabilnog poli(ε-kaprolaktona) za kontrolisano otpuštanje karbamazepina",
pages = "502-491",
number = "6",
volume = "64",
doi = "10.2298/HEMIND101117073P"
}
Pepić, D., Anđelković, D. R., Nikolić, M., Grujić, S.,& Đonlagić, J.. (2010). Optimization of preparation conditions of poly(ε-caprolactone) microspheres for controlled release of carbamazepine. in Hemijska industrija
Association of Chemical Engineers of Serbia., 64(6), 491-502.
https://doi.org/10.2298/HEMIND101117073P
Pepić D, Anđelković DR, Nikolić M, Grujić S, Đonlagić J. Optimization of preparation conditions of poly(ε-caprolactone) microspheres for controlled release of carbamazepine. in Hemijska industrija. 2010;64(6):491-502.
doi:10.2298/HEMIND101117073P .
Pepić, Dragana, Anđelković, Darinka R., Nikolić, Marija, Grujić, Svetlana, Đonlagić, Jasna, "Optimization of preparation conditions of poly(ε-caprolactone) microspheres for controlled release of carbamazepine" in Hemijska industrija, 64, no. 6 (2010):491-502,
https://doi.org/10.2298/HEMIND101117073P . .
1
1
1

Preparation of biodegradable porous poly(butylene succinate) microspheres

Pepić, Dragana; Spasojević, Milica; Nikolić, Marija; Đonlagić, Jasna

(Association of Chemical Engineers of Serbia, 2008)

TY  - JOUR
AU  - Pepić, Dragana
AU  - Spasojević, Milica
AU  - Nikolić, Marija
AU  - Đonlagić, Jasna
PY  - 2008
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/1329
AB  - The aim of this study was to determine the optimal conditions for the fabrication of porous microspheres based on poly(butylene succinate), PBS. The biodegradable non-porous PBS microspheres were prepared by the oil-in-water (o/w) emulsion solvent evaporation method using poly(vinyl alcohol), PVA, as the surfactant. Fabrication conditions, such as stirring rate, organic/aqueous ratio, PBS concentration and surfactant (PVA) concentration, which have an important influence on both the particle size and the morphology of the microspheres, were varied. Scanning electron microscopy, SEM, observations confirmed the size, size distribution and surface morphology of the microspheres. The optimal conditions for the preparation of the non-porous microspheres were found to be: concentration the PBS solution, 10 mass%; PVA concentration, 1 mass%; the organic/ aqueous ratio CHCl3/H2O = 1/20 and stirring rate 800 rpm. Porous PBS microspheres were fabricated under the optimal conditions using various amounts of hexane and poly(ethylene oxide), PEO, as porogens. The influence of the amount of porogen on the pore size and the particle size was investigated using SEM and the apparent density. The microspheres exhibited various porosities and the pore sizes. The average particle size of the microspheres with PEO as the porogen was from 100 to 122μm and that of the microspheres with hexane as the porogen was from 87 to 97μm. The apparent density of the porous microspheres with PEO as the porogen, from 0.16 to 0.23 g/cm3, was much smaller than the non-porous microspheres, 0.40 g/cm3. In the in vitro degradation experiments, the porous microspheres were incubated in phosphate buffer solution (pH 7) at 37°C. After incubating for one month, the microspheres showed significant extent of the hydrolytic degradation of the porous PBS microspheres.
AB  - Cilj ovog rada je bio pronalaženje optimalnih uslova za dobijanje poroznih mikrosfera na bazi biodegradabilnog poli(butilensukcinata), PBS. Neporozne PBS mikrosfere su dobijene emulzionim postupkom uz otparavanje rastvarača u prisustvu poli(vinil alkohola), PVA, kao stabilizatora emulzije. Tokom izrade mikrosfera menjani su uslovi kao što su: brzina mešanja, odnos organska/vodena faza, PBS koncentracija i koncentracija emulgatora (PVA), koji imaju značajan uticaj na veličinu čestica i morfologiju mikrosfera. Skenirajućim elektronskim mikroskopom (SEM) utvrđena je veličina mikrosfera, raspodela veličina čestica kao i morfologija površine mikrosfera. Ustanovljeni su optimalni uslovi za dobijanje neporoznih mikrosfera: koncentracija PBS rastvora od 10 mas%, PVA koncentracija od 1 mas%, odnos organska/vodena faza = 1/20 i brzina mešanja 800 min-1. Porozne PBS mikročestice su pravljene pri optimalnim uslovima u prisustvu različitog sadržaja heksana i poli(etilenoksida), PEO, kao porogena. Kao rezultat dobijeno je da mikrosfere pokazuju različitu poroznost kao i različitu veličinu pora unutar čestica. Srednja veličina čestica mikrosfera kod kojih je korišćen PEO kao porogen bila je od 100 do 122 μm, a kod mikrosfera sa heksanom kao porogenom srednja veličina čestica se kretala od 87 do 97 μm. Prividna gustina poroznih čestica kod mikrosfera sa PEO kao porogenom bila je u opsegu od 0,16 do 0,23 g/cm3, dosta manje od prividne gustine neporoznih mikorsfera, 0,40 g/cm3. In vitro degradacioni testovi poroznih mikrosfera su izvođeni u puferskom rastvoru (pH 7) na 37°C. Posle inkubacije mikrosfera od jednog meseca u puferu ustanovljeno je da dolazi do delimične degradacije polimernih mikrosfera.
PB  - Association of Chemical Engineers of Serbia
T2  - Hemijska industrija
T1  - Preparation of biodegradable porous poly(butylene succinate) microspheres
T1  - Dobijanje poroznih biodegradabilnih mikrosfera poli(butilen sukcinata)
EP  - 338
IS  - 6
SP  - 329
VL  - 62
DO  - 10.2298/HEMIND0806329P
ER  - 
@article{
author = "Pepić, Dragana and Spasojević, Milica and Nikolić, Marija and Đonlagić, Jasna",
year = "2008",
abstract = "The aim of this study was to determine the optimal conditions for the fabrication of porous microspheres based on poly(butylene succinate), PBS. The biodegradable non-porous PBS microspheres were prepared by the oil-in-water (o/w) emulsion solvent evaporation method using poly(vinyl alcohol), PVA, as the surfactant. Fabrication conditions, such as stirring rate, organic/aqueous ratio, PBS concentration and surfactant (PVA) concentration, which have an important influence on both the particle size and the morphology of the microspheres, were varied. Scanning electron microscopy, SEM, observations confirmed the size, size distribution and surface morphology of the microspheres. The optimal conditions for the preparation of the non-porous microspheres were found to be: concentration the PBS solution, 10 mass%; PVA concentration, 1 mass%; the organic/ aqueous ratio CHCl3/H2O = 1/20 and stirring rate 800 rpm. Porous PBS microspheres were fabricated under the optimal conditions using various amounts of hexane and poly(ethylene oxide), PEO, as porogens. The influence of the amount of porogen on the pore size and the particle size was investigated using SEM and the apparent density. The microspheres exhibited various porosities and the pore sizes. The average particle size of the microspheres with PEO as the porogen was from 100 to 122μm and that of the microspheres with hexane as the porogen was from 87 to 97μm. The apparent density of the porous microspheres with PEO as the porogen, from 0.16 to 0.23 g/cm3, was much smaller than the non-porous microspheres, 0.40 g/cm3. In the in vitro degradation experiments, the porous microspheres were incubated in phosphate buffer solution (pH 7) at 37°C. After incubating for one month, the microspheres showed significant extent of the hydrolytic degradation of the porous PBS microspheres., Cilj ovog rada je bio pronalaženje optimalnih uslova za dobijanje poroznih mikrosfera na bazi biodegradabilnog poli(butilensukcinata), PBS. Neporozne PBS mikrosfere su dobijene emulzionim postupkom uz otparavanje rastvarača u prisustvu poli(vinil alkohola), PVA, kao stabilizatora emulzije. Tokom izrade mikrosfera menjani su uslovi kao što su: brzina mešanja, odnos organska/vodena faza, PBS koncentracija i koncentracija emulgatora (PVA), koji imaju značajan uticaj na veličinu čestica i morfologiju mikrosfera. Skenirajućim elektronskim mikroskopom (SEM) utvrđena je veličina mikrosfera, raspodela veličina čestica kao i morfologija površine mikrosfera. Ustanovljeni su optimalni uslovi za dobijanje neporoznih mikrosfera: koncentracija PBS rastvora od 10 mas%, PVA koncentracija od 1 mas%, odnos organska/vodena faza = 1/20 i brzina mešanja 800 min-1. Porozne PBS mikročestice su pravljene pri optimalnim uslovima u prisustvu različitog sadržaja heksana i poli(etilenoksida), PEO, kao porogena. Kao rezultat dobijeno je da mikrosfere pokazuju različitu poroznost kao i različitu veličinu pora unutar čestica. Srednja veličina čestica mikrosfera kod kojih je korišćen PEO kao porogen bila je od 100 do 122 μm, a kod mikrosfera sa heksanom kao porogenom srednja veličina čestica se kretala od 87 do 97 μm. Prividna gustina poroznih čestica kod mikrosfera sa PEO kao porogenom bila je u opsegu od 0,16 do 0,23 g/cm3, dosta manje od prividne gustine neporoznih mikorsfera, 0,40 g/cm3. In vitro degradacioni testovi poroznih mikrosfera su izvođeni u puferskom rastvoru (pH 7) na 37°C. Posle inkubacije mikrosfera od jednog meseca u puferu ustanovljeno je da dolazi do delimične degradacije polimernih mikrosfera.",
publisher = "Association of Chemical Engineers of Serbia",
journal = "Hemijska industrija",
title = "Preparation of biodegradable porous poly(butylene succinate) microspheres, Dobijanje poroznih biodegradabilnih mikrosfera poli(butilen sukcinata)",
pages = "338-329",
number = "6",
volume = "62",
doi = "10.2298/HEMIND0806329P"
}
Pepić, D., Spasojević, M., Nikolić, M.,& Đonlagić, J.. (2008). Preparation of biodegradable porous poly(butylene succinate) microspheres. in Hemijska industrija
Association of Chemical Engineers of Serbia., 62(6), 329-338.
https://doi.org/10.2298/HEMIND0806329P
Pepić D, Spasojević M, Nikolić M, Đonlagić J. Preparation of biodegradable porous poly(butylene succinate) microspheres. in Hemijska industrija. 2008;62(6):329-338.
doi:10.2298/HEMIND0806329P .
Pepić, Dragana, Spasojević, Milica, Nikolić, Marija, Đonlagić, Jasna, "Preparation of biodegradable porous poly(butylene succinate) microspheres" in Hemijska industrija, 62, no. 6 (2008):329-338,
https://doi.org/10.2298/HEMIND0806329P . .
3
2
2
2

Synthesis and characterization of biodegradable aliphatic copolyesters with poly(ethylene oxide) soft segments

Pepić, Dragana; Žagar, Ema; Žigon, Majda; Kržan, Andrej; Kunaver, Matjaz; Đonlagić, Jasna

(Elsevier Ltd, 2008)

TY  - JOUR
AU  - Pepić, Dragana
AU  - Žagar, Ema
AU  - Žigon, Majda
AU  - Kržan, Andrej
AU  - Kunaver, Matjaz
AU  - Đonlagić, Jasna
PY  - 2008
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/5576
AB  - A series of multiblock poly(ether-ester)s based on poly(butylene succinate) (PBS) as the hard segments and hydrophilic poly(ethylene oxide) (PEO) as the soft segments was synthesized with the aim of developing degradable polymers which could combine the mechanical properties of high performance elastomers with those of flexible plastics. The aliphatic poly(ether-ester)s were synthesized by the catalyzed two-step transesterification reaction of dimethyl succinate, 1,4-butanediol and α,ω-hydroxyl terminated poly(ethylene oxide) (PEO, over(M, -)n = 1000 g/mol) in bulk. The content of soft PEO segments in the polymer chains was varied from about 10 to 50 mass%. The effect of the introduction of the soft PEO segments on the structure, thermal and physical properties, as well as on the biodegradation properties was investigated. The composition and structure of these aliphatic segmented copolyesters were determined by 1H NMR spectroscopy. The molecular weights of the polyesters were verified by gel permeation chromatography (GPC), as well as by viscometry of dilute solutions and polymer melts. The thermal properties were investigated using differential scanning calorimetry (DSC). The degree of crystallinity was determined by means of DSC and wide-angle X-ray scattering. A depression of melting temperature and a reduction of crystallinity of the hard segments with increasing content of PEO segments were observed. Biodegradation of the synthesized copolyesters, estimated in enzymatic degradation tests in phosphate buffer solution with Candida rugosa lipase at 37 °C was compared with hydrolytic degradation in the buffer solution. The weight losses of the samples were in the range from 2 to 10 mass%. GPC analysis confirmed that there were significant changes in molecular weight of copolyesters with higher content of PEO segments, up to 40% of initial values. This leads to conclusion that degradation mechanism of the poly(ether-ester)s based on PEO segments occurs through bulk degradation in addition to surface erosion.
PB  - Elsevier Ltd
T2  - European Polymer Journal
T1  - Synthesis and characterization of biodegradable aliphatic copolyesters with poly(ethylene oxide) soft segments
EP  - 917
IS  - 3
SP  - 904
VL  - 44
DO  - 10.1016/j.eurpolymj.2007.11.035
ER  - 
@article{
author = "Pepić, Dragana and Žagar, Ema and Žigon, Majda and Kržan, Andrej and Kunaver, Matjaz and Đonlagić, Jasna",
year = "2008",
abstract = "A series of multiblock poly(ether-ester)s based on poly(butylene succinate) (PBS) as the hard segments and hydrophilic poly(ethylene oxide) (PEO) as the soft segments was synthesized with the aim of developing degradable polymers which could combine the mechanical properties of high performance elastomers with those of flexible plastics. The aliphatic poly(ether-ester)s were synthesized by the catalyzed two-step transesterification reaction of dimethyl succinate, 1,4-butanediol and α,ω-hydroxyl terminated poly(ethylene oxide) (PEO, over(M, -)n = 1000 g/mol) in bulk. The content of soft PEO segments in the polymer chains was varied from about 10 to 50 mass%. The effect of the introduction of the soft PEO segments on the structure, thermal and physical properties, as well as on the biodegradation properties was investigated. The composition and structure of these aliphatic segmented copolyesters were determined by 1H NMR spectroscopy. The molecular weights of the polyesters were verified by gel permeation chromatography (GPC), as well as by viscometry of dilute solutions and polymer melts. The thermal properties were investigated using differential scanning calorimetry (DSC). The degree of crystallinity was determined by means of DSC and wide-angle X-ray scattering. A depression of melting temperature and a reduction of crystallinity of the hard segments with increasing content of PEO segments were observed. Biodegradation of the synthesized copolyesters, estimated in enzymatic degradation tests in phosphate buffer solution with Candida rugosa lipase at 37 °C was compared with hydrolytic degradation in the buffer solution. The weight losses of the samples were in the range from 2 to 10 mass%. GPC analysis confirmed that there were significant changes in molecular weight of copolyesters with higher content of PEO segments, up to 40% of initial values. This leads to conclusion that degradation mechanism of the poly(ether-ester)s based on PEO segments occurs through bulk degradation in addition to surface erosion.",
publisher = "Elsevier Ltd",
journal = "European Polymer Journal",
title = "Synthesis and characterization of biodegradable aliphatic copolyesters with poly(ethylene oxide) soft segments",
pages = "917-904",
number = "3",
volume = "44",
doi = "10.1016/j.eurpolymj.2007.11.035"
}
Pepić, D., Žagar, E., Žigon, M., Kržan, A., Kunaver, M.,& Đonlagić, J.. (2008). Synthesis and characterization of biodegradable aliphatic copolyesters with poly(ethylene oxide) soft segments. in European Polymer Journal
Elsevier Ltd., 44(3), 904-917.
https://doi.org/10.1016/j.eurpolymj.2007.11.035
Pepić D, Žagar E, Žigon M, Kržan A, Kunaver M, Đonlagić J. Synthesis and characterization of biodegradable aliphatic copolyesters with poly(ethylene oxide) soft segments. in European Polymer Journal. 2008;44(3):904-917.
doi:10.1016/j.eurpolymj.2007.11.035 .
Pepić, Dragana, Žagar, Ema, Žigon, Majda, Kržan, Andrej, Kunaver, Matjaz, Đonlagić, Jasna, "Synthesis and characterization of biodegradable aliphatic copolyesters with poly(ethylene oxide) soft segments" in European Polymer Journal, 44, no. 3 (2008):904-917,
https://doi.org/10.1016/j.eurpolymj.2007.11.035 . .
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52

Synthesis and characterization of biodegradable aliphatic copolyesters with poly(tetramethylene oxide) soft segments

Pepić, Dragana; Nikolić, Marija; Đonlagić, Jasna

(Wiley, Hoboken, 2007)

TY  - JOUR
AU  - Pepić, Dragana
AU  - Nikolić, Marija
AU  - Đonlagić, Jasna
PY  - 2007
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/1174
AB  - A series of aliphatic poly(ether-ester)s based on flexible poly(tetramethylene oxide) (PTMO) and hard poly (butylene succinate) (PBS) segments were synthesized by the catalyzed two-step transesterification reaction of dimethyl succinate, 1,4-butanediol, and alpha,omega-hydroxy-terminated PTMO (M-n = 1000 g/mol) in the bulk. The content of soft PTMO segments in the polymer chains was varied from 10 to 50 mass %. The effect of the introduction of the soft segments on the structure, thermal, and physical properties, as well as on the biodegradation properties was investigated. The composition and structure of the aliphatic segmented copolyesters were determined by H-1 NMR spectroscopy. The molecular weights of the polyesters were verified by viscometry of dilute solutions and polymer melts. The thermal properties were investigated using DSC. The degree of crystallinity was determined by means of DSC and WAXS. Biodegradation of the synthesized copolyesters, estimated in enzymatic degradation tests on polymer films in phosphate buffer solution with Candida rugosa lipase at 37 degrees C, was compared with hydrolytic degradation in the buffer solution. Viscosity measurements confirmed that there was no change in molecular weight of the copolyesters leading to the conclusion that the degradation mechanism of poly(ester-ether)s based on PTMO segments occurs through the surface erosion.
PB  - Wiley, Hoboken
T2  - Journal of Applied Polymer Science
T1  - Synthesis and characterization of biodegradable aliphatic copolyesters with poly(tetramethylene oxide) soft segments
EP  - 1786
IS  - 3
SP  - 1777
VL  - 106
DO  - 10.1002/app.26860
ER  - 
@article{
author = "Pepić, Dragana and Nikolić, Marija and Đonlagić, Jasna",
year = "2007",
abstract = "A series of aliphatic poly(ether-ester)s based on flexible poly(tetramethylene oxide) (PTMO) and hard poly (butylene succinate) (PBS) segments were synthesized by the catalyzed two-step transesterification reaction of dimethyl succinate, 1,4-butanediol, and alpha,omega-hydroxy-terminated PTMO (M-n = 1000 g/mol) in the bulk. The content of soft PTMO segments in the polymer chains was varied from 10 to 50 mass %. The effect of the introduction of the soft segments on the structure, thermal, and physical properties, as well as on the biodegradation properties was investigated. The composition and structure of the aliphatic segmented copolyesters were determined by H-1 NMR spectroscopy. The molecular weights of the polyesters were verified by viscometry of dilute solutions and polymer melts. The thermal properties were investigated using DSC. The degree of crystallinity was determined by means of DSC and WAXS. Biodegradation of the synthesized copolyesters, estimated in enzymatic degradation tests on polymer films in phosphate buffer solution with Candida rugosa lipase at 37 degrees C, was compared with hydrolytic degradation in the buffer solution. Viscosity measurements confirmed that there was no change in molecular weight of the copolyesters leading to the conclusion that the degradation mechanism of poly(ester-ether)s based on PTMO segments occurs through the surface erosion.",
publisher = "Wiley, Hoboken",
journal = "Journal of Applied Polymer Science",
title = "Synthesis and characterization of biodegradable aliphatic copolyesters with poly(tetramethylene oxide) soft segments",
pages = "1786-1777",
number = "3",
volume = "106",
doi = "10.1002/app.26860"
}
Pepić, D., Nikolić, M.,& Đonlagić, J.. (2007). Synthesis and characterization of biodegradable aliphatic copolyesters with poly(tetramethylene oxide) soft segments. in Journal of Applied Polymer Science
Wiley, Hoboken., 106(3), 1777-1786.
https://doi.org/10.1002/app.26860
Pepić D, Nikolić M, Đonlagić J. Synthesis and characterization of biodegradable aliphatic copolyesters with poly(tetramethylene oxide) soft segments. in Journal of Applied Polymer Science. 2007;106(3):1777-1786.
doi:10.1002/app.26860 .
Pepić, Dragana, Nikolić, Marija, Đonlagić, Jasna, "Synthesis and characterization of biodegradable aliphatic copolyesters with poly(tetramethylene oxide) soft segments" in Journal of Applied Polymer Science, 106, no. 3 (2007):1777-1786,
https://doi.org/10.1002/app.26860 . .
19
16
25

The influence of antioxidant and post-synthetic treatment on the properties of biodegradable poly(butylene succinate)s modified with poly(propylene oxide)

Pepić, Dragana; Radoičić, Marija; Nikolić, Marija; Đonlagić, Jasna

(Serbian Chemical Society, Belgrade, 2007)

TY  - JOUR
AU  - Pepić, Dragana
AU  - Radoičić, Marija
AU  - Nikolić, Marija
AU  - Đonlagić, Jasna
PY  - 2007
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/1104
AB  - Novel poly(ester-ether)s based on poly(butylene succinate) (PBS) as the hard segments and 30 mass % of poly(propylene oxide) (PPO) as the soft segments were synthesized with varying amount of the antioxidant (N,N'-diphenyl-p-phenylenediamine, DPPD). The influences of the addition of DPPD and the impact of post-synthetic treatment by precipitation on the molecular structure, thermal and physical properties, as well as on the storage stability of the biodegradable aliphatic copolyesters, were investigated. The structure and composition of the copolymers were determined by means of 1H-NMR spectroscopy. The molecular weight and polydispersity of the poly(ester-ether)s were evaluated from solution viscosity and GPC measurements. The thermal properties and stability were evaluated, respecttively, by means of DSC and non-isothermal thermogravimetry in an inert nitrogen atmosphere. The biodegradability potential of the polymers was studied in hydrolytic and enzymatic degradation tests with Candida cylindracea lipase by monitoring the weight loss of polymer films after incubation. The weight losses of the samples increased with time and were in the range from 1 to 5 mass % after 4 weeks. GPC analysis confirmed that there were changes in the molecular weight of the copolyesters during both hydrolytic and enzymatic degradation tests, leading to the conclusion that the degradation mechanism of poly(butylene succinate)s modified with PPO occurred through surface erosion and bulk degradation.
AB  - U okviru ovog rada sintetisani su novi poli(estar-etri) na bazi poli(butilen sukcinata) (PBS) kao tvrdih segmenata i 30 masenih % poli(propilenoksida) (PPO) ugrađenih u meke segmente, bez i u prisustvu antioksidansa N,N′-difenil-p-fenilendiamina (DPPD). Izučavao se uticaj antioksiodansa DPPD kao i načina izdvajanja polimera, odnosno pretaložavanja na strukturu i veličinu molekula, termička i fizička svojstva kao i na stabilnost biodegradabilnih alifatskih kopoliestara. Struktura i sastav kopoliestara su provereni 1H-NMR spektroskopijom. Veličina molekula i raspodela veličina molekula sintetisanih poli(estar-etara) su određeni viskozimetrijom razblaženih rastvora i GPC analizom. Termička svojstva i termička stabilnost poli(estar-etara) su analizirana DSC i neizotermskom termogravimetrijom u inertnoj atmosferi azota. Biodegradabilni potencijal polimera je izučavan u ogledima hidrolotičke i enzimske degradacije u prisustvu lipaze Candida cylindracea prateći promene u masi polimernih filmova tokom inkubacije. Gubici su rasli sa vremenom i posle 4 nedelje su bili u opsegu od 1 do 5 masenih %. GPC analiza je potvrdila da postoje promene u molarnoj masi uzoraka i u ogledima hidrolitičke i enzimske degradacije na osnovu čega se može zaključiti da se mehanizam degradacije poli(estar-etara) na bazi PPO odvija kroz eroziju površine i degradaciju u masi.
PB  - Serbian Chemical Society, Belgrade
T2  - Journal of the Serbian Chemical Society
T1  - The influence of antioxidant and post-synthetic treatment on the properties of biodegradable poly(butylene succinate)s modified with poly(propylene oxide)
T1  - Uticaj antioksiodansa i načina izdvajanja polimera na svojstva biodegradabilnih poli(butilen sukcinata) modifikovanih poli(propilenoksidom)
EP  - 1531
IS  - 12
SP  - 1515
VL  - 72
UR  - https://hdl.handle.net/21.15107/rcub_technorep_1104
ER  - 
@article{
author = "Pepić, Dragana and Radoičić, Marija and Nikolić, Marija and Đonlagić, Jasna",
year = "2007",
abstract = "Novel poly(ester-ether)s based on poly(butylene succinate) (PBS) as the hard segments and 30 mass % of poly(propylene oxide) (PPO) as the soft segments were synthesized with varying amount of the antioxidant (N,N'-diphenyl-p-phenylenediamine, DPPD). The influences of the addition of DPPD and the impact of post-synthetic treatment by precipitation on the molecular structure, thermal and physical properties, as well as on the storage stability of the biodegradable aliphatic copolyesters, were investigated. The structure and composition of the copolymers were determined by means of 1H-NMR spectroscopy. The molecular weight and polydispersity of the poly(ester-ether)s were evaluated from solution viscosity and GPC measurements. The thermal properties and stability were evaluated, respecttively, by means of DSC and non-isothermal thermogravimetry in an inert nitrogen atmosphere. The biodegradability potential of the polymers was studied in hydrolytic and enzymatic degradation tests with Candida cylindracea lipase by monitoring the weight loss of polymer films after incubation. The weight losses of the samples increased with time and were in the range from 1 to 5 mass % after 4 weeks. GPC analysis confirmed that there were changes in the molecular weight of the copolyesters during both hydrolytic and enzymatic degradation tests, leading to the conclusion that the degradation mechanism of poly(butylene succinate)s modified with PPO occurred through surface erosion and bulk degradation., U okviru ovog rada sintetisani su novi poli(estar-etri) na bazi poli(butilen sukcinata) (PBS) kao tvrdih segmenata i 30 masenih % poli(propilenoksida) (PPO) ugrađenih u meke segmente, bez i u prisustvu antioksidansa N,N′-difenil-p-fenilendiamina (DPPD). Izučavao se uticaj antioksiodansa DPPD kao i načina izdvajanja polimera, odnosno pretaložavanja na strukturu i veličinu molekula, termička i fizička svojstva kao i na stabilnost biodegradabilnih alifatskih kopoliestara. Struktura i sastav kopoliestara su provereni 1H-NMR spektroskopijom. Veličina molekula i raspodela veličina molekula sintetisanih poli(estar-etara) su određeni viskozimetrijom razblaženih rastvora i GPC analizom. Termička svojstva i termička stabilnost poli(estar-etara) su analizirana DSC i neizotermskom termogravimetrijom u inertnoj atmosferi azota. Biodegradabilni potencijal polimera je izučavan u ogledima hidrolotičke i enzimske degradacije u prisustvu lipaze Candida cylindracea prateći promene u masi polimernih filmova tokom inkubacije. Gubici su rasli sa vremenom i posle 4 nedelje su bili u opsegu od 1 do 5 masenih %. GPC analiza je potvrdila da postoje promene u molarnoj masi uzoraka i u ogledima hidrolitičke i enzimske degradacije na osnovu čega se može zaključiti da se mehanizam degradacije poli(estar-etara) na bazi PPO odvija kroz eroziju površine i degradaciju u masi.",
publisher = "Serbian Chemical Society, Belgrade",
journal = "Journal of the Serbian Chemical Society",
title = "The influence of antioxidant and post-synthetic treatment on the properties of biodegradable poly(butylene succinate)s modified with poly(propylene oxide), Uticaj antioksiodansa i načina izdvajanja polimera na svojstva biodegradabilnih poli(butilen sukcinata) modifikovanih poli(propilenoksidom)",
pages = "1531-1515",
number = "12",
volume = "72",
url = "https://hdl.handle.net/21.15107/rcub_technorep_1104"
}
Pepić, D., Radoičić, M., Nikolić, M.,& Đonlagić, J.. (2007). The influence of antioxidant and post-synthetic treatment on the properties of biodegradable poly(butylene succinate)s modified with poly(propylene oxide). in Journal of the Serbian Chemical Society
Serbian Chemical Society, Belgrade., 72(12), 1515-1531.
https://hdl.handle.net/21.15107/rcub_technorep_1104
Pepić D, Radoičić M, Nikolić M, Đonlagić J. The influence of antioxidant and post-synthetic treatment on the properties of biodegradable poly(butylene succinate)s modified with poly(propylene oxide). in Journal of the Serbian Chemical Society. 2007;72(12):1515-1531.
https://hdl.handle.net/21.15107/rcub_technorep_1104 .
Pepić, Dragana, Radoičić, Marija, Nikolić, Marija, Đonlagić, Jasna, "The influence of antioxidant and post-synthetic treatment on the properties of biodegradable poly(butylene succinate)s modified with poly(propylene oxide)" in Journal of the Serbian Chemical Society, 72, no. 12 (2007):1515-1531,
https://hdl.handle.net/21.15107/rcub_technorep_1104 .
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