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"ABSTRAKHidrogel poli(N-vinil pirrolidon) terikat silang telah disintesis dengan menggunakan agen pengikat silang etilen glikoldimetakrilat (EGDMA) dan NN?-metilenbisakrilamid (MBAm), inisiator benzoil peroksida dan pelarut etanol melalui teknik polimerisasi radikal bebas. Dilakukan variasi jenis dan konsentrasi agen pengikat silang serta waktu reaksi. Hidrogel yang terbentuk dikarakterisasi menggunakan FT-IR dan analisa gravimetri. Ditemukan bahwa hidrogel PNVP terikat silang dengan baik jika digunakan MBAm 5% sebagai agen pengikat silang daripada EGDMA dengan waktu reaksi 24 jam. Hidrogel PNVP-MBAm ini memiliki derajat ikat silang yang lebih tinggi daripada PNVP-EGDMA yaitu 28,8% dengan kemampuan menyerap air sekitar 250%. Derajat ikat silang berbanding terbalik dengan kemampuan hidrogel menyerap air atau mengembang (swelling). Semakin lama waktu reaksi, semakin banyak ikatan silang yang terbentuk. Semakin tinggi derajat ikat silang maka semakin rendah kemampuan hidrogel dalam menyerap air.

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ABSTRACTThis article describes about the synthesis of chemically crosslinked hydrogels poly(N-vinyl pirrolidone) (PNVP) by free radical polymerization in solution technique. Ethylene glycoldimethacrylate and NN?-methylenebisacrylamide were used as crosslinker, benzoyl peroxide was used as initiator and ethanol was used as a solvent. Hydrogels were prepared by varying the type and concentration of crosslinker, and also reaction time. Resulted hydrogels were characterized by FT-IR and gravimetry analysis. Crosslinked hydrogels PNVP by using crosslinker MBAm 5% with 24 hours reaction time had the highest degree of crosslinking about 28,8% and 250% for its swelling ratio. The degree of crosslinking inversely proportional with hydrogels ability to absorp water (swelling). The longer reaction time was, the higher degree of crosslink was. The higher degree of crosslink was, the lower swelling ability of the hydrogels was."

"Hidrogel termosensitif N-vinil kaprolaktam (NVCL) disintesis dengan metode polimerisasi radikal bebas ikat silang. Agen pengikat silang etilen glikol dimetakrilat (EGDMA) dan N,N?-metilen bis akrilamida (MBA) digunakan untuk menentukan pengaruh dari jenis dan konsentrasi pengikat silang pada nilai persen fraksi gel dan swelling saat setimbang. Spektrum Fourier Transform Infra Red Spectroscopy (FTIR) membuktikan pemutusan dari ikatan C=C untuk berpolimerisasi sebagai hidrogel. Hasil menunjukkan bahwa semakin tinggi konsentrasi pengikat silang, semakin tinggi fraksi gel namun rasio swelling semakin rendah. Ditemukan bahwa MBA merupakan agen pengikat silang yang lebih efektif dari EGDMA dengan nilai fraksi gel 35,72% pada MBA 5%. Kondisi optimal yang diperoleh yaitu waktu reaksi 24 jam dengan nilai persen gelation sebesar 14,29%.

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Thermosensitive N-vinyl caprolactam (NVCL) hydrogels were synthesized by a free radical crosslinking polymerization. Ethylene glycol dimethacrylate (EGDMA) and N,N?-methylene bisacrylamide (MBA) crosslinking agents were employed in order to determine the effects of crosslinker type and concentration in percentage of gel fraction and equilibrium swelling value (ESV). Fourier Transform Infra Red Spectroscopy (FTIR) spectrum confirmed the breaking bond of C=C to polymerize as hydrogel.

Results showed that higher concentration of crosslinking agent, higher fraction gel but swelling ratio decreased. It was found that MBA more effective than EGDMA in synthesis PNVCL hydrogel with 35,72% gel fraction at 5% MBA. Optimum condition was 24 hour reaction time with percentage of gelation 14,29%."

"Sintesis hidrogel kitosan-poli(N-vinil-2-pirolidon) (PNVP) dengan metode full-Interpenetrating Polymer Network (full-IPN) dilakukan secara bertahap (sequential). Tahap pertama yaitu melakukan sintesis jaringan polimer kitosan terikat silang asetaldehida melalui homogenisasi. Tahap kedua yaitu melakukan sintesis jaringan PNVP terikat silang N, N?-metilenbisakrilamida (MBA) melalui reaksi polimerisasi radikal bebas dari monomer NVP dengan agen pengikat silang MBA dan inisiator amonium persulfat (APS). Hidrogel kitosan-PNVP full-IPN yang dihasilkan, memiliki kekuatan ikat silang lebih baik yang teramati dari nilai derajat ikat silang serta dapat mempertahankan kemampuan swelling dengan baik yang teramati dari nilai rasio swelling dibandingkan dengan hidrogel kitosan.Hasil optimum dari rasio swelling dan derajat ikat silang pada hidrogel kitosan-PNVP full-IPN sebesar 149,8% dan 85,4% dengan komposisi kitosan:monomer NVP yaitu 70:30 (b/b %), waktu reaksi polimerisasi 0,5 jam, konsentrasi MBA 1% (b/b), serta konsentrasi APS 1% (b/b). Karakterisasi dilakukan dengan Spektrofotometer Fourier Transform Infrared (FTIR), Differential Scanning Calorimetry (DSC), dan Scanning Electron Microscope (SEM).

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Synthesis of hydrogel chitosan-poly(N-vinyl-2-pyrrolidone) (PNVP) by full-Interpenetrating Polymer Network was performed in stages (sequential method). The first stage was the synthesis of chitosan polymer network by crosslinked with acetaldehyde under homogenization process. The second stage was the synthesis which was PNVP of crosslinked with N,N?-methylenebisacrylamide (MBA) through free radical polymerization reaction of NVP monomer, was used as the crosslink agent MBA and ammonium persulfate (APS) as the initiator. The synthesized hydrogel chitosan-PNVP full-IPN has a good strength due to the observed crosslinking structure observed the value of crosslinking degree and the good swelling capability by the value of swelling ratio compared with hydrogel chitosan.

The optimum result of swelling ratio and the degree of crosslinking from hydrogel chitosan-PNVP full-IPN were 149,8% and 85,4% which were obtained with the composition chitosan:NVP monomer of 70:30 (w/w %), the polymerization reaction time of 0,5 hours, the concentration MBA 1% (w/w), and the concentration APS 1% (w/w). Products characterizations were done by Fourier Transform Infrared Spectrophotometer (FTIR), Differential Scanning Calorimetry (DSC), dan Scanning Electron Microscope (SEM)."

"Amoksisilin trihidrat memiliki waktu tinggal yang singkat di dalam lambung sehingga kurang efektif untuk pengobatan infeksi Helicobacter pylori. Sistem penghantar obat mengapung dikembangkan agar obat dapat bertahan di lambung dalam waktu yang lama. Pada penelitian ini, disintesis hidrogel kitosan-poli N-vinil-pirrolidon full-IPN sebagai matriks penghantar obat amoksisilin trihidrat dengan sistem mengapung yang mengandung agen pembentuk pori K2CO3 dan KHCO3. Adapun konsentrasi agen pembentuk pori yang di tambahkan yaitu 0 , 1 , 5 , 10 , dan 15. Pengaruh konsentrasi dan jenis agen pembentuk pori terhadap rasio swelling, derajat ikat silang, porositas, floating time dan floating lag time diteliti dan karakterisasi sifat hidrogel lebih lanjut dilakukan dengan spektroskopi Fourier Transform Infra Red FTIR dan mikroskop stereo optik. Penambahan KHCO3 15 merupakan konsentrasi optimum untuk hidrogel kitosan-PNVP berdasarkan floating time dan floating lag time. Selanjutnya dilakukan enkapsulasi amoksisilin trihidrat secara in situ dan post loading ke dalam hidrogel. Uji efisiensi enkapsulasi dan disolusi matriks hidrogel K-PNVP terloading amoksisilin trihidrat dilakukan secara in vitro pada pH lambung. Hidrogel kitosan-PNVP in situ loading menghasilkan efisiensi enkapsulasi sebesar 80 dan disolusi sebesar 94 . Sementara pada hidrogel kitosan-PNVP post loading menghasilkan efisiensi enkapsulasi sebesar 53 dan disolusi sebesar 76.

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Amoxicillin trihydrate has a short residence time in stomach so it is less effective for the treatment of Helicobacter pylori infections. Floating drug delivery system is developed so that the drug can survive in stomach for a long time. In this study, full IPN hydrogel chitosan poly n vinyl pyrrolidone is synthesized as matrix for drug delivery system containing pore forming agents K2CO3 and KHCO3. Concentration of the pore forming agent added is 0 , 1 , 5 , 10 , and 15 . The effect of concentration and type of pore forming agent against swelling ratio, the degree of crosslink, porosity, floating time and floating lag time will be studied and characterization of hydrogel properties performed by Fourier Transform Infra Red FTIR and a stereo optic microscope.

The addition of KHCO3 15 is the optimum concentration for hydrogel K PNVP according to floating time and floating lag time. Furthermore, Amoxicillin trihydrate is loaded to hydrogel K PNVP by using in situ loading and post loading methods. Encapsulation efficiency and release of matrix hydrogel K PNVP loaded by amoxicillin trihydrate examined by in vitro studies at stomach rsquo s pH. Encapsulation efficiency of hydrogel K PNVP in situ loading is 80 and the release is 94. While, encapsulation efficiency of hydrogel K PNVP post loading is 53 and the release is 76. "

"Kopolimerisasi merupakan salah satu cara untuk mendapatkan polimer dengan sifat swelling lebih baik. Sintesis hidrogel kopoli(N-vinilpirrolidon/N-vinilkaprolaktam) menggunakan variasi jenis dan konsentrasi agen pengikat silang serta waktu reaksi. Hidrogel hasil polimerisasi dikarakterisasi dengan FTIR, DSC, SEM serta diuji melalui analisa gravimetri. Didapatkan hasil sintesis hidrogel dengan agen pengikat silang MBA mempunyai derajat ikat silang yang lebih baik dibandingkan dengan EGDMA dalam waktu 24 jam reaksi. Derajat silang hidrogel dengan MBA 5% yang didapat sebesar 84.81% memiliki persen swelling yang rendah. Persen swelling maksimal sebesar 87.04% didapatkan pada hidrogel dengan agen pengikat silang EGDMA 3% dan waktu reaksi 8 jam. Derajat ikat silang berbanding terbalik dengan hasil kemampuan mengembang atau menyerap air (swelling). Hidrogel yang tersintesis dengan waktu reaksi semakin lama, konsentrasi agen pengikat silang semakin tinggi, maka derajat ikat silang hidrogel semakin tinggi mengakibatkan semakin menurunnya kemampuan hidrogel menyerap air. Hasil karakterisasi hidrogel dengan DSC menunjukkan hanya terdapat satu nilai Tg 180 oC dan terjadi pergeseran nilai Tg dari nilai Tg secara teoritis 151 oC karena pengaruh agen pengikat silang. Hidrogel kopoli(N-vinilpirrolidon/N-vinilkaprolaktam) terikat silang telah berhasil disintesis.

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Copolymerization is one of the ways to get better swelling properties of the polymer. Synthesis of hidrogel copoly(N-N-vinilpirrolidon/vinilkaprolaktam) using a variety of types of binding agent and concentration of Crosslinker and time of reaction. Hidrogel characterized by FTIR, DSC, SEM as well as tested through analysis of gravimetric analysis. Synthesis of the results obtained with the crosslinking agents hidrogel MBA has degree of crosslinking is better compared to EGDMA within 24 hours of the reaction. Degree of Crosslinking hidrogel with MBA 5% earned 84.81% has a low percent swelling. Percent of maximum swelling 87.04% obtained on crosslinking agents with hidrogel EGDMA 3% and the time of reaction of 8 hours. Degree of Crosslinking is inversely proportional to the results the ability expands or absorb water (swelling). Hydrogel was synthesized with longer time of reaction and high concentration of crosslinker, it makes degree of crosslinking have increase and the swelling ability of hydrogel was decrease. Characterization of hidrogel with DSC indicates there is only one value of Tg is 180 oC and Tg values shift from Tg value theoretically 151 oC due to the influence of the crosslinking agents. Hydrogel crosslinked copoly(N-N vinilpirrolidon/vinilkaprolaktam) has been successfully synthesized."

"Hidrogel kitosan-cangkok-poli(N-vinil pirrolidon) telah disintesis melalui teknik polimerisasi radikal bebas. Dalam penelitian ini, monomer N-vinil pirrolidon (NVP) dicangkokkan pada kitosan menggunakan inisiator ammonium persulfat (APS) dan agen pengikat silang N,N’-metilen bisakrilamida (MBA) dalam sistem larutan. Untuk membuktikan bahwa monomer itu telah tercangkok, dilakukan karakterisasi dengan Fourier Transform Infrared Spectroscopy (FTIR), Differential Scanning Calorimetry (DSC), dan Scanning Electron Microscope (SEM) untuk mengetahui bentuk morfologi hidrogel. Pengaruh komposisi monomer NVP, agen pengikat silang, dan waktu polimerisasi terhadap kemampuan swelling telah diamati. Swelling optimum diperoleh sebesar 54,6% pada waktu polimerisasi 3 jam dengan komposisi monomer NVP 0,8 mL dan konsentrasi pengikat silang 2%.

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Hydrogels of chitosan-graft-poly(N-vinylpyrrolidone) had been synthesized via free radical polymerization technique. In this research, monomer N-vinylpyrrolidone (NVP) was grafted onto chitosan by using APS as initiator and N,N '-methylene bisacrylamide (MBA) as crosslinking agent in the solution system. In order to prove that the monomers were grafted, FTIR spectroscopy, DSC analysis were used, and Scanning Electron Microscope (SEM) to determine the morphology of hydrogels. The influence monomer compositions, concentration of crosslinking agent, and polymerization time on the ability of swelling was observed. The optimum swelling was obtained at 54,6% in the polymerization time of 3 hours with 0.8 mL NVP monomer composition and concentration of crosslinking of 2%."

"Metode semi-Interpenetrating Polymer Network (semi-IPN) dapat digunakan untuk mensintesis hidrogel. Pada metode ini, jaringan kitosan terikat silang formaldehida akan berinteraksi dengan poli(N-vinil pirolidon) linear. Secara umum, rasio sweling dan derajat ikat silang hidrogel semi-IPN dipengaruhi oleh komposisi kitosan-PVP, konsentrasi formaldehida, dan waktu reaksi. Rasio swelling dan derajat ikat silang dari hidrogel kitosan-poli(N-vinil pirolidon) semi-IPN didapatkan sebesar 553,70% dan 58,82% pada rasio kitosan-poli(N-vinil pirolidon) 70:30 (%b/b), konsentrasi formaldehida 2% (%b/b), dan waktu reaksi 3 jam. Hidrogel kitosan-poli(N-vinil pirolidon) semi-IPN menunjukkan penurunan rasio swelling dan peningkatan derajat ikat silang dibandingkan hidrogel kitosan nonkovalen.

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Semi-Interpenetrating Polymer Network (semi-IPN) method was used to synthesize hydrogel. In this method, chitosan was crosslinked with formaldehyde and blended with Poly(N-vinyl pyrrolidone) to form crosslinked chitosan network that interracts with linear polymer of Poly(N-vinyl pyrrolidone). Generally, swelling ratio and degree of crosslinking of semi-IPN hydrogel were influenced by Poly(N-vinyl pyrrolidone) amount, concentration of formaldehyde, and reaction time. Swelling ratio and degree of crosslinking of semi-IPN hydrogel was obtained at 553,70% and 58,82% in the ratio of chitosan- Poly(N-vinyl pyrrolidone) 70:30 (%w/w), formaldehyde concentration of 2%, and 3 hours of reaction time. Semi-IPN hydrogel of chitosan-Poly(N-vinyl pyrrolidone) has lower swelling ratio and higher degree of crosslinking compared to hydrogel of chitosan."

"Hidrogel merupakan polimer superabsorben yang dapat menyerap dan menahan sejumlah besar medium cair. Hidrogel kitosan-graft-poli(N-vinil pirrolidon) atau kitosan-graft-PNVP disintesis melalui proses polimerisasi radikal bebas. Polimer ini diikatsilangkan pada rantai cabang, rantai PNVP, dengan agen pengikat silang yang berbeda, yaitu N,N’-Metilen Bisakrilamida (MBA) dan Etilen Glikol Dimetakrilat (EGDMA). Kemampuan swelling hidrogel kitosan-graft-PNVP terikat silang dilakukan dengan merendamnya dalam media cair. Pengaruh jenis dan konsentrasi agen pengikat silang serta waktu reaksi terhadap daya absorbsi air telah diamati. Hidrogel yang terikat silang dengan EGDMA memperlihatkan rasio swelling lebih besar dibandingkan dengan hidrogel yang terikat silang dengan MBA. Kemampuan menyerap hidrogel yang terikat silang dengan EGDMA dapat mencapai 50% dari berat sebelum menyerap air. Produk ini dikarakterisasi menggunakan Fourier Transform Infrared Spectroscopy (FTIR), Differential Scanning Calorimetry (DSC) dan Scanning Electron Microscope (SEM).

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Hydrogels are superabsorbent polymer that it can be able to absorb and retain large amounts of aqueous fluids. Hydrogel chitosan-graft-poly(N-vinyl pirrolidone) or chitosan-graft-PNVP has been synthesized by free radical polymerization. It is synthesized by crosslinking in the branch chains, PNVP chains, with different crosslinking agents, i.e. N,N’-Methylene Bisacrylamide (MBA) dan Ethylene Glycol Dimethacrylate (EGDMA). The swelling behavior of the crosslingked chitosan-graft-PNVP was measured by immerse it in the water. The effect of different and concentration of crosslinked agents and also reaction time on water absorbency have been investigated. Crosslinked hydrogel by using crosslinker EGDMA had showed that swelling ratio is higher than crosslinked hydrogel by using crosslinker MBA. The swelling behavior of crosslinked hydrogel by using crosslinker EGDMA can absorb water until 50% from its weight before absorbed. Resulted hydrogels were characterized by Fourier Transform Infrared Spectroscopy (FTIR), Differential Scanning Calorimetry (DSC) and Scanning Electron Microscope (SEM)."

"Pengobatan umum infeksi Helicobacter pylori dengan amoksisilin trihidrat tidak cukup efektif karena sediaan konvensional yang digunakan memiliki waktu retensi yang cukup singkat di dalam lambung. Pada penelitian ini, amoksisilin trihidrat akan dienkapsulasi ke dalam hidrogel full-IPN kitosan-poli N-vinilkaprolaktam sebagai matriks sistem penghantar obat mengapung yang dapat mengatasi masalah tersebut. Agen pembentuk pori yang digunakan adalah K2CO3 dan KHCO3 dengan konsentrasi 1 , 5 , 10 , 15 dan 20 . Pengaruh konsentrasi dan jenis agen pembentuk pori terhadap rasio swelling, derajat ikat silang, porositas, floating time dan floating lag time akan diteliti dan karakterisasi sifat hidrogel lebih lanjut dilakukan dengan spektroskopi Fourier Transform Infra Red FTIR dan mikroskop stereo optik. Hidrogel K-PNVCL dengan penambahan agen pembentuk pori KHCO3 15 yang menghasilkan sifat optimal kemudian diloading dengan amoksisilin trihidrat secara in situ dan post loading. Efisiensi enkapsulasi dan disolusi matriks hidrogel K-PNVCL terloading amoksisilin trihidrat dilakukan secara in vitro pada pH lambung. Hidrogel K-PNVCL optimum yang diloading dengan metode in situ loading menghasilkan efisiensi enkapsulasi sebesar 86,3 dan disolusi sebesar 95,3. Sementara pada hidrogel K-PNVCL optimum yang diloading menggunakan metode post loading menghasilkan efisiensi enkapsulasi sebesar 72,7 dan disolusi sebesar 99,8.

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Common treatment of Helicobacter pylori infections with amoxicillin trihydrate are not sufficiently effective because the conventional dosage used has a fairly short retention time in stomach. In this study, amoxicillin trihydrate will be encapsulated into hydrogel full IPN chitosan poly N vinylcaprolactam as a matrix in floating drug delivery system that can solve these problems. Pore forming agent that used is K2CO3 and KHCO3 with concentration 1 , 5 10 , 15 and 20. The effect of concentration and type of pore forming agent against swelling ratio, the degree of crosslink, porosity, floating time and floating lag time will be studied and characterization of hydrogel properties performed by Fourier Transform Infra Red FTIR and a stereo optic microscope.

Hydrogel K PNVCL with the addition of pore forming agent KHCO3 15 that provide the optimum properties then be loaded by amoxicillin trihydrate with in situ loading and post loading method. Encapsulation efficiency and dissolution of matrix hydrogel K PNVCL loaded by amoxicillin trihydrate examined by in vitro studies at stomach rsquo s pH. Optimum hydrogel K PNVCL that loaded with in situ loading method produces encapsulation efficiency of 86,3 and dissolution of 95,3 . While the optimum hydrogel loaded using post loading method produces encapsulation efficiency of 72,7 and 99,8 of dissolution."

"Pada penelitian ini dilakukan sintesis polimer suspensi poli[stirena-ko-(butil akrilat)] melalui polimerisasi radikal bebas untuk mempelajari pengaruh komposisi monomer stirena dan butil akrilat terhadap temperatur transisi gelas (Tg) kopolimer, serta mempelajari pengaruh konsentrasi inisiator benzoil peroksida terhadap solid content, viskositas dan ukuran partikel kopolimer. Dari hasil penelitian diperoleh bahwa, komposisi monomer mempengaruhi nilai Tg kopolimer, dengan semakin banyak komposisi monomer stirena yang digunakan, semakin tinggi nilai Tg kopolimer yang dihasilkan. Komposisi monomer optimum diperoleh pada saat perbandingan komposisi antara stirena dengan butil akrilat 55:45, dengan Tg yang dihasilkan sebesar 38,18ºC. Konsentrasi inisiator mempengaruhi nilai solid content dan viskositas, akan tetapi tidak mempengaruhi ukuran partikel kopolimer. Konsentrasi inisiator optimum diperoleh pada saat konsentrasi inisiator 1% dari berat monomer total, dengan nilai solid content yang dihasilkan sebesar 39,34% dan viskositas kopolimer sebesar 781,25 centiPoise. Karakterisasi menggunakan FTIR, GPC dan DSC menunjukkan bahwa polimer suspensi poli[stirena-ko-(butil akrilat)] telah berhasil disintesis.

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In this research, suspension polymers of poly[styrene-co-(butyl acrylate)] synthesis was done by using free radical polymerization method to study not only the effects of various monomer composition of styrene and butyl acrylate on the glass transition temperature (Tg), but also to study the effects of various initiator concentration of benzoyl peroxide on the solid content, viscosity and particle size of copolymer. The result showed that monomer composition affected the Tg of copolymers. The more amount of styrene used, the higher value of Tg copolymers produced. Optimum monomer composition was obtained when the composition ratio between styrene and butyl acrylate 55:45, with the value of Tg of 38,18ºC. Initiator concentration affected the value of solid content and viscosity, but didn?t affect the particle size of copolymer. Optimum initiator concentration was obtained when the initiator concentration 1% from the total weight of monomers, with the value of solid content of 39,34% and the viscosity of 781,25 centiPoise. The FTIR, GPC and DSC result showed that suspension polymers of poly[styrene-co-(butyl acrylate)] has been successfully synthesized."