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Sherley
Abstrak :
Senyawa antibiotika memegang peranan penting di dalam pengobatan berbagai macam penyakit infeksi baik yang disebabkan oleh mikroba maupun yang disebabkah oleh virus. Senyawa - antibiotika UK-3 telah diisolasi dari miselium Streptomyces-sp. 517-02 -dan diketahui mempunyai aktivitas dalam menghambat pertumbuhan bakteri dan sel kanker. Total sintesis senyawa UK-3 dan analognya juga telah dilakukan. Penelitian ini bertujuan untuk mensmtesis senyawa Analog UK-3 (SH-I, SH-3) yang diharapkan mempunyai aktivitas yang lebih besar dari senyawa aslinya. Metode sintesis yang digunakan adalah melalui tiga tahap reaksi. Tahap pertama adalah reaksi esterifika L-seiin dan heksanol dengan katalis asam p-TsOH dalam bonzen. Selanjutnya pada tahap kedua adalah pembentukan 2-hidroksinikotinil-heksil-serin-ester antara asam 2-hidroksinikotinat dan heksilserin-ester-p-TsOH dengan katalis/aktivator DMAP/DCC dalam piridin. Reaksi terakhir adalah esterifikasi senyawa 2-hidroksinikotinil-serin-heksil-ester dengan anhidrida asetat dalam piridin menghasilkan SH-l, dengan asam fenil propanoat dan oktanoat dengan DMAP/DCC dalamdiklorometan masing-masing menghasilkan SH-2 dan SH-3. Senyawa hasil sintesis diidentifikasi dengan menggunakan spektrofotometer Infra Merah (FT-IR), spektrometer Resonansi Magnetik-Inti (1H-NMR), spektrofotometer, Ultra Violet dan -spektrometer- Massa (MS). Pengujian aktivitas senyawa analog UK-3 dilakukan dengan uji antimikroba-terhadap beberapa mikroba dan uji toksisitas terhadap Brine Shrimp. Senyawa SH-3 aktif menghambat pertumbuhan terhadap bakteri Escherichia coil dan Candida albicans sampai konsentrasi 75 ppm, sedang SH-2 menunjukkan aktivitas paling tinggi terhadap uji Brine Shrimp dengan nilai LC50 pada konsentrasi 700,22 ppm.
The Synthesis And Biological Activity Test Of Antibiotic UK-3 Analogues (2-idroxynicotinyl-Hexyl-Serine-Ester-And Its Derivatives) Antibiotic compounds play important role in medical treatment of various infection diseases either caused by microbes or viruses. The Antibiotic UK-3 has been isolated from mycelim Streptomyces sp. 517-02 and found that its activity inhibits the growth of bacteria and cancer cells. Total synthesis of UK-3 and its analogues have been conducted as well. The goal of this research is to synthesize various analogues of UK-3 (SH-1, SH-2, SH-3) which is hoped to have higher activities than that of the original compound. The synthesis method consist of three reaction steps. The first step is esterification reaction of -L-serine and hexanol with catalyst p-TsOH in -benzene. The -second -step is the formation of -2-hydroxynicotinyl-hexyl-serine-ester between 2-hydroxynicotinyl acid and hexyl-serine-ester with catalyst/activator DMAPIDCC in pyridine. The last reaction is esterification of 2 hydroxynicotinyl-serine-ester-compound and acetic-anhydrid in pyridine - which form SH-1. If phenyl propionic acid or octanoic acid was used in the presence of DCCIDMAP in dichloromethane, the product formed was SH-2 and SH-3. The product of each step was identified and characterized by means Infra Red spectrophotometer (FTIR), 1H-NMR spectrometer, UV spectrophotometer and Mass spectrometer. The activity of SH-l, SH-2 and SH-3 as antimicrobes tested against several microorganism and their toxicity was tested against Brine Shrimp. SH-3 was found active against E. coil and C. albicans up to the concentrations of 75 ppm, while SH-2 indicated the highest activity on Brine Shrimp test with the value of LC50 in the concentrations of 700,22 ppm.
Depok: Universitas Indonesia, 1998
T-Pdf
UI - Tesis Membership  Universitas Indonesia Library
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Nenden Solihatul Zannah
Abstrak :
Tagetes erecta merupakan tanaman yang memiliki bunga berwarna kuning hingga Oranye yang mengandung senyawa α-terthienyl (2,2′:5′,2′′-Terthiophene) yang bersifat nematosidal dan toksik terhadap eritrosit dan kulit manusia. Penelitian ini bertujuan untuk menganalisis kandungan senyawa α-terthienyl (2,2′:5′,2′′-Terthiophene) dalam bunga Tagetes erecta Indonesia yang berasal dari beberapa daerah di Jawa Barat, yaitu Cipanas, Lembang, dan Rancaekek. Bunga yang digunakan adalah bunga berwarna kuning dan Oranye. Bunga diekstraksi dengan menggunakan waterbath shaker pada suhu 65 oC selama 1 jam menggunakan pelarut n-heksan, kemudian n-heksan diuapkan dan ekstrak kental yang dihasilkan dilarutkan dengan etanol dengan bantuan sonikasi. Ekstrak etanol kemudian dianalisis secara secara KLT, HPLC, dan LC-MS/MS. Berdasarkan hasil KLT, semua bunga mengandung senyawa α-terthienyl (2,2′:5′,2′′-Terthiophene) yang ditandai dengan adanya bercak yang sejajar dengan baku α-terthienyl (2,2′:5′,2′′-Terthiophene) dengan warna yang sama, yaitu warna biru keunguan yang diamati di bawah sinar 366 nm. Kandungan α-terthienyl (2,2′:5′,2′′-Terthiophene) yang diuji dengan HPLC dan LC-MS/MS memberikan hasil yang sama, dimana pada setiap daerah, bunga berwarna Oranye memiliki kandungan α-terthienyl (2,2′:5′,2′′-Terthiophene) yang lebih tinggi dari bunga berwarna kuning. ......Tagetes erecta is a plant that has yellow to orange flowers containing α-terthienyl (2,2′:5′,2′′-Terthiophene) compounds which are nematocidal and toxic to erythrocytes and human skin. This study aims to analyze the content of α-terthienyl (2,2′:5′,2′′-Terthiophene) compounds in Indonesian Tagetes erecta flowers originating from several regions in West Java, namely Cipanas, Lembang, and Rancaekek. The flowers used are yellow and orange flowers. The flowers were extracted using a waterbath shaker at 65 oC for 1 hour using n-hexane solvent, then the n-hexane was evaporated and the resulting viscous extract was dissolved with ethanol by sonication. The ethanol extract was then analyzed using TLC, HPLC, and LC-MS/MS. Based on the TLC results, all flowers contain the compound α-terthienyl (2,2′:5′,2′′-Terthiophene) which is characterized by the presence of spots parallel to the standard α-terthienyl (2,2′:5′,2′′-Terthiophene) with the same color, namely the purplish-blue color observed under 366 nm of light. The content of α-terthienyl (2,2′:5′,2′′-Terthiophene) analysed by HPLC and LC-MS/MS gave the same results, where in each region, orange-colored flowers contained α-terthienyl (2,2′:5′,2′′-Terthiophene) which is higher than yellow flowers.
Depok: Fakultas Matematika dan Ilmu Pengetahuan Alam Universitas Indonesia, 2021
T-Pdf
UI - Tesis Membership  Universitas Indonesia Library
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Gultom, Okto Riristina
Abstrak :
Berkurangnya sumber daya bahan bakar fosil ditambah dengan peningkatan konsumsi energi, menyebabkan produksi bahan bakar menjadi tidak seimbang tingkat konsumsinya. Untuk itu perlu dilakukan pengembangan sumber bahan bakar alternatif yang berasal dari tanaman. Minyak kelapa sawit dan jelantah banyak digunakan sebagai bahan utama biodiesel karena kelimpahan material serta harga yang terjangkau. Pada penelitian ini dilakukan sintesis biodiesel pada minyak kelapa sawit dan jelantah dengan metode elektrolisis menggunakan sel elektrokimia dua kompartemen yang dilengkapi dengan elektroda Boron Doped Diamond sebagai katoda. Membran Nafion ditempatkan diantara kompartemen sel sebagai pemisah. Elektrolisis dilakukan pada campuran minyak kelapa sawit, metanol dan tetrahidrofuran. Selain itu sebanyak 2% air (b/b) ditambahkan ke dalam campuran. Ion hidroksil (OH-) dari hasil elektrolisis air dalam katoda diharapkan dapat mengkatalisis pembentukan ion metoksi (CH3O-) yang berperan dalam pembentukan biodiesel jenis fatty acid metil ester (FAME). Sebagai elektrolit digunakan Na2SO4 atau tetra butyl ammonium perklorat (TBAP). Hasil elektrolisis dianalisis dengan metoda kromatografi gas. Setelah proses elektrolisisselama 2,5 jam, hasil yang diperoleh sebagai %FAME sebesar 7,7% untuk minyak kelapa sawit dan 6,5% untuk minyak jelantah. ......Fossil fuels resources shortages as well as the increase of energy consumption resulting in an unbalance fuel production against the consumption level. In this case, the fuel production is way lower than the fuel consumption. Therefore, it is necessary to develop an alternative fuel sources derived from plants. For instance, palm oil and waste cooking oil, which are widely used as the main source for biodiesel due to its availability and affordable price. In this research, the synthesis of biodiesel using palm oil and waste cooking oil by electrolysis method equipped with two compartements electrochemical cell and a boron doped diamond electrode as the cathode was performed. Nafion® membrane was placed between the cell compartements as the separator. The electrolysis was performed in palm oil mixture, methanol, tetrahydrofuran, and 2% water (%w/w). The hydroxyl ions (OH-)product from the electrolysis of water in the cathode is expected to catalyze the formation of methoxy ion (CH3O-) which plays the role in the formation of Fatty Acid Methyl Esther (FAME). Na2SO4 or tetrabutylammonium percholrate (TBAP) were used as the electrolyte. The biodesel product was analyzed by gas chromatrography method. After 2,5 hour electrolysis process, the results showed the FAME conversion of palm oil was 7,7 % and was 6,5 % for the used cooking oil.
Depok: Fakultas Matematika dan Ilmu Pengetahuan Alam Universitas Indonesia, 2015
T42677
UI - Tesis Membership  Universitas Indonesia Library
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Rahayu Amanda Putri
Abstrak :
Kelapa sawit merupakan salah satu komoditas unggulan di Indonesia. Selama ini, minyak kelapa sawit banyak digunakan untuk minyak goreng dan sebagian kecil untuk oleokimia. Konsumsi produk ester semakin penting bagi manusia. Salah satunya adalah metil ester yang banyak digunakan sebagai bahan baku dari alkanolamida. Pada penelitian ini, dilakukan suatu reaksi transesterifikasi dan interesterifikasi minyak kelapa sawit secara enzimatis menggunakan lipase Candida rugosa EC 3.1.1.3 terimobilisasi pada partikel nano Fe3O4-Polidopamin. Partikel nano Fe3O4 disintesis dengan menggunakan metode kopresipitasi dan dilapisi dengan dopamin yang kemudian dikarakterisasi menggunakan FTIR, EDS, dan FESEM. Lipase Candida rugosa terimobilisasi pada partikel nano Fe3O4-Polidopamin kemudian ditentukan persen loading dan aktivitasnya. Hasil produk transesterifikasi dan interesterifikasi minyak kelapa sawit dianalisis menggunakan GC-MS dan GC-FID. Hasil karakterisasi FTIR dan EDS menunjukan partikel nano Fe3O4 dan Fe3O4-Polidopamin berhasil disintesis. Hasil FESEM menunjukan Fe3O4 dan Fe3O4-polidopamin memiliki ukuran masing-masing sekitar 25,33-28,30 nm, 38,89-44,5 nm. Persen loading enzim terimobilisasi partikel nano Fe3O4-Polidopamin sebesar 69,8%. Aktivitas spesifik untuk reaksi lipase Candida rugosa bebas sebesar 7,85 U/mg, sedangkan untuk lipase terimobilisasi pada partikel nano Fe3O4-polidopamin sebesar 4,98 U/mg. Pada karakterisasi menggunakan GC-FID, reaksi transesterifikasi dengan lipase bebas % total komposisi etil ester yaitu sebesar 82,42%, untuk propil ester 48,31%, sedangkan untuk lipase terimobilisasi % total komposisi etil ester 65,02%, propil ester 32,89%. Pada reaksi interesterifikasi dengan lipase bebas % total komposisi etil ester yaitu sebesar 39,94%, untuk propil ester 32,35%, sedangkan untuk lipase terimobilisasi % komposisi etil ester 24,41%, propil ester 21,4%. Karakterisasi GC-MS hasil transesterifikasi dan interesterifikasi dengan lipase bebas dan lipase terimobilisasi didapatkan fragmen metil palmitat, metil oleat, etil palmitat dan propil palmitat.
Palm is one of the leading commodity in Indonesia. Palm oil is widely used for cooking oil and small portion for oleochemical. Consumption of ester product is increasingly important for humans. One of them is methyl esters are widely used as raw materials of alkanolamide. In this research, have done enzymatic reaction of transesterification and interesterification using Lipase Candida rugosa EC 3.1.1.3 immobilized on Fe3O4-Polydopamine nanoparticles as a catalyst. Fe3O4 nanoparticle was synthesized by the copresipitation methods and coated by dopamine. Nanoparticles were then characterized by FTIR, EDS and FESEM. Immobilized lipase then used for the transesterification and interesterification reaction and its result characterized using GC-FID and GC-MS. FESEM result showed Fe3O4 and Fe3O4-polydopamine has size about 25,33-28,30 nm and 38,89-44,5 nm. Percent loading lipase Candida rugosa immobilized Fe3O4-polydopamine is 69,8%. Free Candida rugosa lipase used in this reaction has spesific activity of 7,85 U/mg. Otherwise, immobilized Candida rugosa lipase on Fe3O4-polydopamine has spesific activity of 4,98 U/mg. Characterization using GC-FID, transesterification with free lipase % total composition of ethyl ester is 82,42% and propyl ester 48,31%. While for lipase immobilized % total composition of ethyl ester is 65,02%, propyl ester is 32,89%. Interesterification with lipase free % total ethyl ester is 39,94%, for propyl ester is 32,35%, while for lipase immobilized % composition ethyl ester 24,41%, propyl ester 21,4%. Characterization using GC-MS transesterification and interesterification with lipase free and lipase immobilized obtained fragments of methyl palmitate, methyl oleic, ethyl palmitate and propyl palmitate.
Depok: Universitas Indonesia, 2014
T43360
UI - Tesis Membership  Universitas Indonesia Library
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Deni Mustika
Abstrak :
ABSTRAK Sistem sol polikarbosilan, toluen dan N,N-dimetilformamida (DMF) dilaporkan dapat menghasilkan serat SiC dengan metode electrospinning yang dilanjutkan dengan proses curing dan pirolisis, namun serat yang dihasilkan memiliki kisaran diameter yang cukup besar dan pada sebagian besar komposisi sol, serat electrospun yang dihasilkan tidak homogen, terdapat partikel atau bead, dan bahkan tidak terbentuk serat. Penelitian ini, difokuskan pada keterkaitan karakteristik sistem sol polikarbosilan (Nabond), toluen dan N,Ndimetilformamida (DMF) terhadap kemampuan pintal listrik (elektrospinnabilitas) dan karakteristik serat yang dihasilkan. Dari penelitian diperoleh bahwa Polikarbosilan (PCS) Nabond dengan berat molekul rerata 1500 ? 2500 g/mol dan indeks distribusi berat molekul 2,0 larut sempurna dalam toluen dan DMF serta dapat dilakukan pemintalan listrik dengan konsentrasi PCS 1,2 - 1,3 g/mL dan persentase DMF 20 - 30 %. Serat kualitas baik diperoleh pada sol 1,3 g/mL PCS dalam 30 % DMF / toluen dengan viskositas 109,25 mPa.S, tegangan listrik 10 kV dan jarak kolektor 12 cm, menghasilkan serat dengan densitas 2,8154 g/cm3, diameter rerata 4,138 μm, luas muka 4,614e+01 m2/g dan memiliki mikropori dengan radius 1-3 nm. Karakterisasi difraksi sinar-X menunjukkan sudah terbentuk β SiC, SEM EDS menunjukkan kadar karbon serat setelah curing dan pirolisis menurun dibanding serat hasil electrospinning dan kadar oksigen meningkat karena teroksidasi. Morfologi serat dengan SEM memperlihatkan serat yang terbentuk berbentuk bulat dengan sedikit cekungan dan tanpa patahan. Analisis DTA memperlihatkan terjadi proses endotermik dan proses eksotermik yang mengkonfirmasi lepasnya bahan organik dan perubahan fasa. TG sampai suhu 500 oC memperlihatkan terjadi peningkatan masa yang signifikan menunjukan terjadinya proses oksidasi. Analisis FTIR pada serat curing menunjukan penurunan serapan Si-H dan Si-CH3 dan serapan Si-O-Si dan Si-O-C meningkat.
ABSTRACT The system of polycarbosilane (PCS), toluene and N,N-dimethylformamide (DMF) can be used to synthesize SiC fiber by electrospinning. Among known problems of the process are wide heterogeneity of the fiber, generation of bead particles, and fiber malformation. An experiment and a characterization of the system to obtain an optimum electrospinning process to synthesize SiC fiber had been conducted. Experiment results showed that Polycarbosilane (PCS) Nabond with a mean molecular weight of 1500 ? 2500 g/mol and molecular weight distribution index 2,0 was completely soluble in toluene and DMF. Electrospinning could be performed at a PCS concentration of 1.2 to 1.3 g/mL in 20 ? 30 % DMF. Best fiber was obtained at 1.3 g/ mL PCS in 30% DMF with viscosity of 109,25 mPa.S, a voltage of 10 kV and a collector distance of 12 cm. The resulting fiber had a density of 2.8154 g/cm3, a mean diameter of 4.138 μm, a surface area 4,614e+01 m2/g and micropores with a radius of 1 to 3 nm. XRD characterization showed that β SiC had formed, SEM EDS showed that the carbon content of the fiber was reduced after curing and pyrolisis, while its oxygen content increased because of oxidation. SEM showed that fiber was spherical, having few hollow and without fracture. DTA showed the existence the endothermic and exothermic processes which confirmed the release of organic material and the phase transformation. TG at up to 500 ° C showed a significant mass increase as a result of oxidation. FTIR showed a decrease in the absorption of Si-H and Si-CH3 while absorption of Si-O-Si and Si-O-C increased.
Depok: Fakultas Matematika dan Ilmu Pengetahuan Alam Universitas Indonesia, 2014
T43356
UI - Tesis Membership  Universitas Indonesia Library
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Wirya Sarwana
Abstrak :
[ABSTRAK
Peningkatan kesadaran akan ancaman polusi lingkungan mendorong pengembangan pengolahan limbah yang lebih efisien dan berkesinambungan. Material semikonduktor TiO2 merupakan material yang diharapkan memegang peranan penting dalam penyelesaian permasalahan polusi lingkungan melalui pemanfaatan energi matahari berbasis perangkat fotovoltaik termodifikasi. Sistem hibrid Dye Sensitized Solar Cell (DSSC)-katalisis merupakan salah satu pendekatan penyelesaian permasalahan limbah dikarenakan dapat mengoksidasi berbagai senyawa limbah serta pengaktifan dalam jangkauan panjang gelombang sinar tampak menyebabkan sistem ini menjadi lebih efisien.

Pada penelitian ini, fabrikasi sistem hibrid DSSC-katalisis menggunakan TiO2 nanotube yang disintesis melalui teknik Rapid Breakdown Anodization pada beda potensial 15 V dalam elektrolit 0,15 M HClO4. Pengujian performa sistem hibrid DSSC-katalisis menggunakan simulasi limbah rhodamine B dalam air. Beberapa variasi yang dilakukan adalah zat warna yang digunakan, perbandingan luas daerah warna dan daerah katalisis, serta perbandingan komposisi campuran fase anatase-rutil dalam TiO2. Variasi ini dilakukan untuk mengetahui kondisi optimum device DSSC-katalisis dalam mendegradasi rhodamine B.

TiO2 hasil sintesis dikalsinasi pada suhu 400°C selama 3 jam dan 2 jam serta 500°C selama 3 jam, lalu dikarakterisasi menggunakan XRD, UV Vis DRS, FTIR, FESEM, dan EDX. Hasil karakterisasi UV-Vis DRS menunjukkan band gap TiO2 hasil sintesis berkisar antara 3-3,5 eV. Sementara hasil uji FTIR yang menunjukkan ada puncak spesifik disekitar daerah 400-700 cm-1. Pada FESEM EDX, terlihat hasil yang cukup baik dalam bentuk bundle nanotube yang membuktikan bahwa teknik RBA dapat digunakan dalam proses sintesis TiO2 nanotube.

TiO2 hasil sintesis digunakan untuk merangkai sistem hibrid DSSC-katalisis menggunakan rhodamine B dan ekstrak buah naga sebagai zat warnanya. Zona katalisis pada hibrid DSSC diuji aktivitas katalisisnya, dimana persen degradasi oleh sistem bersensitizer rhodamine B sebesar 65,22% dan ekstrak buah naga sebesar 34,78% dengan lama penyinaran masing-masing 60 menit. Hal ini menunjukkan bahwa dalam sistem ini, rhodamine B memberikan hasil yang lebih baik. Pengujian selanjutnya menggunakan sensitizer rhodamine B dengan variasi perbandingan luas zona warna dan zona katalisis sebesar 1:2, 1:1, dan 1:0,5 dan diperoleh persen degradasi berturut-turut 40,19%; 25,01% ; dan 9,59%. Dengan demikian perbandingan optimum pada variasi ini adalah luas zona warna dan katalis yang paling baik adalah 1:2. Pengujian ketiga menggunakan TiO2 dengan komposisi campuran fase kristal anatase rutil sebesar 100% anatase 0% rutil.
ABSTRACT
An increasing concern on environmental pollution lead to development for more efficient and sustainable waste treatment. Titanium dioxide is expected to play an important role to solve the environmental pollution problem by using solar energy based on modified photovoltaic devices. Hybrid Dye Sensitized Solar Cell (DSSC) -catalysis system may become an efficient approach to solve the problem not only causes of the oxidizing power to degrade almost organic non biodegradable compounds in the waste but also the activation energy of this system still in visible light range. In this study, fabrication of hybrid DSSC - catalysis system used TiO2 nanotubes which was synthesized by Rapid Breakdown Anodization method, the potential difference was 15 V in 0.15 M HClO4. Degradating ability testing for hybrid DSSC ?catalysis system using simulated waste rhodamine B dispersed in water. Several variations has been done as kind of the dye used for the system, the wide comparison of dyes zone and catalytic zone, and composition of mixed crystalline phase ratio of anatase and rutile in TiO2 used. The purpose of the variation was to determine the optimum conditions for DSSC - catalysis device in degrading rhodamine B. TiO2 synthesized was calcined up to 400 ° C for 3 hours and 2 hours and 500°C for 3 hours. It was characterized using XRD, UV- Vis DRS, FTIR, FESEM, and EDX. UV- Vis DRS showed the band gap of samples between 3-3.5 eV. The result of FTIR measurements showed there was peak around the region 400-700 cm-1. FESEM EDX results showed very good shape of TiO2 nanotube bundle which proves that the RBA technique can be used in the synthesis process. Testing for determine the better sensitizer between rhodamine B and dragon fruit extract has been done. Based on the results of UV Vis measurements, percent degradation of rhodamine B system up to 65.22% and dragon fruit extract only 34.78%. Each of them exposure by visible light for 60 minutes. It indicates that in this system, rhodamine B sensitizer gives the better results. Further testing using sensitizer rhodamine B with a wide comparison of dye zone and catalytic zones by 1: 2, 1: 1 and 1: 0.5 and obtained percent of degradation respectively 40.19%; 25.01%; and 9.59%. Thus the optimum ratio in this variation is 1: 2. The third testing using the composition of the mixture TiO2 anatase-rutile crystalline phase 100% anatase 0% rutile, 92.88% anatase 7.12% rutile and 17.08% anatase 82.92% rutile with a percent of degradation for each sample were 66.80%, 81.01%, and 70.37%. The test results showed that the best phase in the system is the mixture of anatase 92.88% rutile 7.12%. Based on the three variations known that the system would work better if using rhodamine B as a;An increasing concern on environmental pollution lead to development for more efficient and sustainable waste treatment. Titanium dioxide is expected to play an important role to solve the environmental pollution problem by using solar energy based on modified photovoltaic devices. Hybrid Dye Sensitized Solar Cell (DSSC) -catalysis system may become an efficient approach to solve the problem not only causes of the oxidizing power to degrade almost organic non biodegradable compounds in the waste but also the activation energy of this system still in visible light range. In this study, fabrication of hybrid DSSC - catalysis system used TiO2 nanotubes which was synthesized by Rapid Breakdown Anodization method, the potential difference was 15 V in 0.15 M HClO4. Degradating ability testing for hybrid DSSC ?catalysis system using simulated waste rhodamine B dispersed in water. Several variations has been done as kind of the dye used for the system, the wide comparison of dyes zone and catalytic zone, and composition of mixed crystalline phase ratio of anatase and rutile in TiO2 used. The purpose of the variation was to determine the optimum conditions for DSSC - catalysis device in degrading rhodamine B. TiO2 synthesized was calcined up to 400 ° C for 3 hours and 2 hours and 500°C for 3 hours. It was characterized using XRD, UV- Vis DRS, FTIR, FESEM, and EDX. UV- Vis DRS showed the band gap of samples between 3-3.5 eV. The result of FTIR measurements showed there was peak around the region 400-700 cm-1. FESEM EDX results showed very good shape of TiO2 nanotube bundle which proves that the RBA technique can be used in the synthesis process. Testing for determine the better sensitizer between rhodamine B and dragon fruit extract has been done. Based on the results of UV Vis measurements, percent degradation of rhodamine B system up to 65.22% and dragon fruit extract only 34.78%. Each of them exposure by visible light for 60 minutes. It indicates that in this system, rhodamine B sensitizer gives the better results. Further testing using sensitizer rhodamine B with a wide comparison of dye zone and catalytic zones by 1: 2, 1: 1 and 1: 0.5 and obtained percent of degradation respectively 40.19%; 25.01%; and 9.59%. Thus the optimum ratio in this variation is 1: 2. The third testing using the composition of the mixture TiO2 anatase-rutile crystalline phase 100% anatase 0% rutile, 92.88% anatase 7.12% rutile and 17.08% anatase 82.92% rutile with a percent of degradation for each sample were 66.80%, 81.01%, and 70.37%. The test results showed that the best phase in the system is the mixture of anatase 92.88% rutile 7.12%. Based on the three variations known that the system would work better if using rhodamine B as a;An increasing concern on environmental pollution lead to development for more efficient and sustainable waste treatment. Titanium dioxide is expected to play an important role to solve the environmental pollution problem by using solar energy based on modified photovoltaic devices. Hybrid Dye Sensitized Solar Cell (DSSC) -catalysis system may become an efficient approach to solve the problem not only causes of the oxidizing power to degrade almost organic non biodegradable compounds in the waste but also the activation energy of this system still in visible light range. In this study, fabrication of hybrid DSSC - catalysis system used TiO2 nanotubes which was synthesized by Rapid Breakdown Anodization method, the potential difference was 15 V in 0.15 M HClO4. Degradating ability testing for hybrid DSSC ?catalysis system using simulated waste rhodamine B dispersed in water. Several variations has been done as kind of the dye used for the system, the wide comparison of dyes zone and catalytic zone, and composition of mixed crystalline phase ratio of anatase and rutile in TiO2 used. The purpose of the variation was to determine the optimum conditions for DSSC - catalysis device in degrading rhodamine B. TiO2 synthesized was calcined up to 400 ° C for 3 hours and 2 hours and 500°C for 3 hours. It was characterized using XRD, UV- Vis DRS, FTIR, FESEM, and EDX. UV- Vis DRS showed the band gap of samples between 3-3.5 eV. The result of FTIR measurements showed there was peak around the region 400-700 cm-1. FESEM EDX results showed very good shape of TiO2 nanotube bundle which proves that the RBA technique can be used in the synthesis process. Testing for determine the better sensitizer between rhodamine B and dragon fruit extract has been done. Based on the results of UV Vis measurements, percent degradation of rhodamine B system up to 65.22% and dragon fruit extract only 34.78%. Each of them exposure by visible light for 60 minutes. It indicates that in this system, rhodamine B sensitizer gives the better results. Further testing using sensitizer rhodamine B with a wide comparison of dye zone and catalytic zones by 1: 2, 1: 1 and 1: 0.5 and obtained percent of degradation respectively 40.19%; 25.01%; and 9.59%. Thus the optimum ratio in this variation is 1: 2. The third testing using the composition of the mixture TiO2 anatase-rutile crystalline phase 100% anatase 0% rutile, 92.88% anatase 7.12% rutile and 17.08% anatase 82.92% rutile with a percent of degradation for each sample were 66.80%, 81.01%, and 70.37%. The test results showed that the best phase in the system is the mixture of anatase 92.88% rutile 7.12%. Based on the three variations known that the system would work better if using rhodamine B as a, An increasing concern on environmental pollution lead to development for more efficient and sustainable waste treatment. Titanium dioxide is expected to play an important role to solve the environmental pollution problem by using solar energy based on modified photovoltaic devices. Hybrid Dye Sensitized Solar Cell (DSSC) -catalysis system may become an efficient approach to solve the problem not only causes of the oxidizing power to degrade almost organic non biodegradable compounds in the waste but also the activation energy of this system still in visible light range. In this study, fabrication of hybrid DSSC - catalysis system used TiO2 nanotubes which was synthesized by Rapid Breakdown Anodization method, the potential difference was 15 V in 0.15 M HClO4. Degradating ability testing for hybrid DSSC –catalysis system using simulated waste rhodamine B dispersed in water. Several variations has been done as kind of the dye used for the system, the wide comparison of dyes zone and catalytic zone, and composition of mixed crystalline phase ratio of anatase and rutile in TiO2 used. The purpose of the variation was to determine the optimum conditions for DSSC - catalysis device in degrading rhodamine B. TiO2 synthesized was calcined up to 400 ° C for 3 hours and 2 hours and 500°C for 3 hours. It was characterized using XRD, UV- Vis DRS, FTIR, FESEM, and EDX. UV- Vis DRS showed the band gap of samples between 3-3.5 eV. The result of FTIR measurements showed there was peak around the region 400-700 cm-1. FESEM EDX results showed very good shape of TiO2 nanotube bundle which proves that the RBA technique can be used in the synthesis process. Testing for determine the better sensitizer between rhodamine B and dragon fruit extract has been done. Based on the results of UV Vis measurements, percent degradation of rhodamine B system up to 65.22% and dragon fruit extract only 34.78%. Each of them exposure by visible light for 60 minutes. It indicates that in this system, rhodamine B sensitizer gives the better results. Further testing using sensitizer rhodamine B with a wide comparison of dye zone and catalytic zones by 1: 2, 1: 1 and 1: 0.5 and obtained percent of degradation respectively 40.19%; 25.01%; and 9.59%. Thus the optimum ratio in this variation is 1: 2. The third testing using the composition of the mixture TiO2 anatase-rutile crystalline phase 100% anatase 0% rutile, 92.88% anatase 7.12% rutile and 17.08% anatase 82.92% rutile with a percent of degradation for each sample were 66.80%, 81.01%, and 70.37%. The test results showed that the best phase in the system is the mixture of anatase 92.88% rutile 7.12%. Based on the three variations known that the system would work better if using rhodamine B as a]
2015
T43280
UI - Tesis Membership  Universitas Indonesia Library
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Ilmi Fadhilah Rizki
Abstrak :
Caulerpa lentillifera termasuk dalam genus Caulerpa yang umumnya ditemukan di perairan tropis dan subtropis. Polisakarida merupakan komponen terbesar yang terdapat pada rumput laut, dan memiliki beberapa aktivitas biologis yang berpotensi sebagai obat. Oleh karena itu, penelitian ini bertujuan untuk mengekstrak dan mengevaluasi polisakarida pada Caulerpa lentillifera sebagai bahan bioaktif antidiabetes. Sampel dimaserasi dengan etanol dan direndam selama semalaman pada suhu ruang. Selanjutnya, residu diekstraksi dengan air pada suhu 75oC selama tiga jam. Pengendapan filtrat dilakukan dengan penambahan etanol untuk sehingga diperoleh ekstrak kasar sebesar 4,16%. Ekstrak kasar dimurnikan dengan menggunakan kolom DEAE-Sepharose dengan hasil rendemean yang diperoleh sebesar 14,8%. Kedua ekstrak tersebut kemudian dikarakterisasi dengan menganalisis total karbohidrat dan sulfat dengan menggunakan spektrofotometer UV-Vis, gugus fungsional dengan menggunakan FT-IR, komponen gula dengan menggunakan HPLC, dan analisis 1H-NMR. Aktifitas antidiabetes kedua ekstrak tersebut dianalisis secara in vitro dengan metode penghambatan enzim α-glukosidase. Berdasarkan hasil analisis tersebut, ekstrak yang telah dimurnikan memberikan aktivitas antidiabetes yang lebih tinggi dibandingkan dengan ekstrak kasar. ......Caulerpa lentillifera belongs to Caulerpa genus which is commonly found in tropical and subtropical waters. Polysaccharides are the largest component found in seaweed, and have several biological activities that have the potential in medicinal. Therefore, this study aims to extract and evaluate the polysaccharides in Caulerpa lentillifera as antidiabetic bioactive material. The sample was macerated by adding ethanol and soaked overnight at room temperature. Furthermore, the dry residue was extracted by water at 75oC for three hours. The filtrate precipitation was done by adding ethanol and the crude extract was obtained 4.16%. The crude extract was purified using the DEAE-Sepharose column with the resulting yield obtained 14.8%. Both extracts were then characterized by analyzing total carbohydrates and sulfates using a UV-Vis spectrophotometer, functional groups using FT-IR, sugar components using HPLC, and 1H-NMR analysis. The antidiabetic activity of the two extracts was analyzed by in vitro by the α-glucosidase inhibition method. Based on the results of the analysis, purified polysaccharide extract gave higher antidiabetic activity than crude extract.
Depok: Fakultas Matematika dan Ilmu Pengetahuan Alam Universitas Indonesia, 2019
T54495
UI - Tesis Membership  Universitas Indonesia Library
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Endah Kristiana
Abstrak :
Keamanan obat tidak hanya bergantung pada bahan aktif obat itu sendiri tetapi juga bergantung pada cemaran yang terkandung di dalamnya. 1,2,3,9-Tetrahidro-9-metil-3-metilen-4H-karbazol-4-one, atau sering disebut Ondansetron Cemaran D merupakan cemaran pada Ondansetron yang dapat membahayakan kesehatan manusia jika nilainya diatas batas minimum (0,1%) karena bersifat racun. Metode analisis kualitatif dan kuantitatif Ondansetron Cemaran D yang selektif dan akurat perlu dikembangkan untuk menjamin kualitas obat. Analisis kualitatif dan kuantitatif cemaran pada obat sering kali tidak dapat dilakukan karena terkendala harga baku pembanding cemaran yang mahal. Penelitian ini bertujuan mendapatkan Ondansetron Cemaran D yang memenuhi syarat karakterisasi dan kemurnian sebagai calon baku pembanding cemaran; serta mendapatkan metode analisis cemaran Ondansetron Cemaran D baik secara kualitatif maupun kuantitatif pada Ondansetron Tablet yang valid secara KCKT. Metodologi penelitian dilakukan dengan cara menghidrolisis Ondansetron dalam suasana basa dengan konsentrasi NaOH 1M selama 30 jam pada suhu 80oC. Hasil hidrolisis Ondansetron Cemaran D yang terbentuk sebesar 34,38% (n=20, SD=1,10%, RSD=3,19%). Ondansetron Cemaran D hasil degradasi telah berhasil disolasi dengan pelarut etil asetat dan eluen heksan-etil asetat (6:4). Isolat Ondansetron Cemaran D dikarakterisasi menggunakan Spektroskopi Inframerah, Kromatografi Gas Spektroskopi Massa, KCKT-DAD, dan 1H-NMR, 13C-NMR, 2D-NMR. Kemurnian Ondanseton Cemaran D diukur menggunakan KCKT-DAD dan diperoleh purity index sebesar 1,0000 dan kemurnian sebesar 99,50% (n=20, SD= 0,11%, RSD=0,11%), dan secara DSC diperoleh kemurnian sebesar 99,66% dan titik leleh sebesar 127,66oC. Parameter validasi metode analisis secara KCKT berupa spesifisitas/selektifitas, uji kesesuaian sistem, linieritas dan rentang, akurasi, ketegaran dan LOD/LOQ. Hasil validasi memenuhi syarat kriteria keberterimaan pada semua parameter validasi dan dapat digunakan sebagai metode kualitatif dan kuantitatif untuk uji Ondansetron Cemaran D pada sampel Ondansetron Tablet. Ondansetron Cemaran D diaplikasikan dalam uji kualitatif dan kuantitatif pada sampel Ondanetron Tablet dan membuktikan adanya Ondansetron Cemaran D pada sampel. ...... Drug safety does not only depend on the active ingredient of the drug itself but also depends on the contamination contained in it. 1,2,3,9-Tetrahidro-9-methyl-3-methylene-4H-carbazol-4-one, or often called Impurity D Ondansetron is contamination on Ondansetron which can endanger human health if the value is above the minimum (0.1 %) due to it is toxicity. The qualitative and quantitative methods of selective and accurate Impurity D Ondansetron need to be developed to ensure the quality of the drug. Qualitative and quantitative analysis of drug contamination is often not possible due to it is constrained by the high-price of standart contaminant. The aim of this study is to obtain Impurity D Ondansetron that fullfilled requirements for characterization and purity as candidate for standard impurity; and obtain a method of analysis of Impurity D Ondansetron both qualitatively and quantitatively on tablet Ondansetron which is valid in HPLC. The research experiments were carried out by hydrolyzing Ondansetron in alkaline condition with optimum concentration NaOH 1M for 30 hours at 80oC. The result of hydrolysis of Impurity D Ondansetron was 34.38% (n = 20, SD = 1.10%, RSD = 3.19%). Impurity D Ondansetron from degradation was succesfully isolated by ethyl acetate as a solvent and hexane-ethyl acetate (6:4) as a eluent. Impurity D Ondansetron was characterized using Infrared Spectroscopy, Mass Spectroscopic Gas Chromatography, KCKT-DAD, and 1H-NMR, 13C-NMR, 2D-NMR. The purity of Impurity D Ondanseton was measured using KCKT-DAD and obtained purity index of 1.0000 and purity of 99.50% (n = 20, SD = 0.11%, RSD = 0.11%), and DSC purity of 99.66% and melting point of 127.66oC. The validation parameter of the HPLC analysis method involve specificity/selectivity, system suitability test, linearity and range, accuracy, robustnes and LOD / LOQ. The results have fullfilled the quality requirement for all validation parameters and can be used as a qualitative and quantitative method for testing Impurity D Ondansetron on Ondansetron Tablets. Impurity D Ondansetron was applied in qualitative and quantitative tests on Ondansetron tablets and proven the presence of Impurity D Ondansetron in the sample.
Depok: Fakultas Matematika dan Ilmu Pengetahuan Alam Universitas Indonesia, 2019
T54497
UI - Tesis Membership  Universitas Indonesia Library
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Fitrana Kurniawan An`nur
Abstrak :
ABSTRAK
Sampai sekarang proses Haber Bosch adalah pilihan utama bagi industri untuk memproduksi gas nitrogen amonia. Proses ini membutuhkan suhu dan tekanan yang sangat tinggi, dan sumber hidrogen dari bahan bakar fosil, yang kemudian menghasilkan emisi gas CO2 yang sangat besar. Oleh karena itu diperlukan alternatif proses lain untuk mensintesis amonia, yang menggunakan energi lebih rendah dalam produksi dan sumber hidrogen yang ramah lingkungan. Dalam penelitian ini sistem tandem antara sel surya tersensitasi zat warna (DSSC) dan sel fotoelektrokimia (PEC) telah dikembangkan. Sel DSSC disiapkan menggunakan pewarna N719 untuk fotoanoda TiO2. Zona PEC menggunakan komposit TiO2 nanotube-BiOBr, di mana reduksi nitrogen menjadi amonia terjadi, sedangkan elektroda counternya adalah Ti3 + -TiO2 di mana oksidasi fotokatalitik air terjadi untuk menyediakan sumber proton. Zona DSSC yang dikembangkan pada sistem tandem DSSC-PEC menunjukkan efisiensi sel surya hingga 7,22%, sementara secara keseluruhan sistem ini memberikan efisiensi konversi foton menjadi amonia sekitar 0,005%. Dengan hanya menggunakan sumber energi cahaya tampak dan air sebagai sumber proton, jumlah amonia terbaik yang dapat diproduksi di bawah kondisi iradiasi di daerah DSSC dan Ti3 + -TiO2 selama 24 jam adalah 0,1 mikromol.
ABSTRACT
Until now the Haber-Bosch process is the main choice for industry to producing ammonia form nitrogen gas. The process need very high temperatures and pressures, and hydrogen source from fossil fuels, which then produce very large CO2 gas emissions. Therefore we need other alternative process to synthesize ammonia, which use a lower energy in the production and environmental friendly hydrogen source. In this study a tandem system between dyes sensitized solar cells (DSSC) and photoelectrochemical cell (PEC) has been developed. The DSSC cells were prepared using N719 dyes sensitized TiO2 photoanode. The PEC zone employed a composite of TiO2 nanotube-BiOBr, where the reduction of nitrogen into ammonia takes place, while its counter electrode was Ti3+-TiO2 where photocatalytic oxidation of water taken place to provide a source of protons.The DSSC zone of the developed DSSC-PEC tandem system showed solar cell efficiency up to 7.22%, while as a whole the system provide photon to ammonia generation approximately 0.005%. By solely visible light energy source and water as proton source, the best ammonia amount that can be produced under irradiation conditions in DSSC and Ti3+-TiO2 areas for 24 hours is 0.1 micromol.
2019
T54478
UI - Tesis Membership  Universitas Indonesia Library
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Qurratu A`yun
Abstrak :
Lantanum-Metal Organic Frameworks (La-MOFs) berhasil disintesis mengunakan metode solvotermal berbasis ligan perylene-3,4,9,10-tetracarboxylic sebagai linker organik dan ion logam lantanum (La3+) sebagai pusat kluster. Pada penelitian ini, dilakukan variasi sintesis La-MOFs melalui parameter perbandingan rasio molar dan waktu reaksi. Tidak adanya serapan pada bilangan gelombang 1700 cm-1 sebagai vibrasi ulur v(C=O) untuk La-MOFs, mengindikasikan atom oksigen dari ligan dapat berkoordinasi dengan ion logam lantanum. Hal ini menandakan La-MOFs telah berhasil terbentuk. Intensitas puncak X-ray difraksi yang kuat dan tajam mengindikasikan kristalinitas La-MOFs yang cukup tinggi. La-MOFs dengan perbandingan rasio molar 0,33:0,25 dan 0,29:0,29 secara berturut-turut memiliki luas permukaan sebesar 72,445 m2/g dan 102,565 m2/g. La-MOFs dengan perbandingan rasio molar 0,33:0,25 dan 0,29:0,29 secara berturut-turut memiliki nilai band gap sebesar 2,686 eV dan 2,732 eV. La-MOFs 0,33:0,25 yang memiliki band gap terkecil digunakan pada aplikasi fotokatalisis untuk produksi gas hidrogen. Hasil voltametri siklik dari La-MOFs 0,33:0,25 diperoleh nilai potensial reduksi (LUMO) sebesar -2,0735 V vs NHE dimana lebih negatif dari potensial reduksi H+/H2 maka dapat disimpulkan bahwa La-MOFs memiliki potensi persyaratan termodinamika untuk reduksi H+/H2. Produksi gas hidrogen tertinggi diperoleh pada massa La-MOFs 0,03 gram yang mencapai 8463,742 µmol.
Lanthanum-Metal Organic Frameworks (La-MOFs) have been successfully synthesized based on perylene-3,4,9,10-tetracarboxylic dyes as organic linker and ion lanthanum (La3+) as cluster center using solvothermal methods. In this study, parameters variations in the synthesis of La-MOFs were carried out through the ratio of molar ratios and reaction time. The absence of absorption at wave number 1700 cm-1 as vibration stretching v(C═O) from La-MOFs, indicates that the oxygen atom from ligand can coordinate with the lanthanum metal ion. This indicates that La-MOFs has been successfully formed. Peak intensity of strong and sharp from X-ray diffraction indicates the high crystallinity of La-MOFs. La-MOFs with a ratio of molar ratios of 0.33:0.25 and 0.29:0.29 respectively have a surface area of ​​72.445 m2/g and 102.565 m2/g. La-MOFs with molar ratios of 0.33: 0.25 and 0.29:0.29 have a band gap value of 2.686 eV and 2.732 eV, respectively. La-MOFs 0.33:0.25 which has the smallest band gap used in photocatalytic applications for hydrogen gas production. The results of cyclic voltammetry from La-MOFs 0.33:0.25 obtained a reduction potential value (LUMO) of -2.0735 V vs. NHE which was more negative than the H+/H2 reduction potential, it can be concluded that La-MOFs have potential thermodynamic requirements for reduction of H+/H2. The highest production of hydrogen gas was obtained at the La-MOFs mass of 0.03 g which reached 8463.742 µmol.
Depok: Fakultas Matematika dan Ilmu Pengetahuan Alam Universitas Indonesia, 2019
T54479
UI - Tesis Membership  Universitas Indonesia Library
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