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"Ion tripolifosfat (P3O10-5) merupakan salah satu bentuk fosfat yang umumnya ditemukan pada limbah deterjen. Apabila tidak diolah dapat menyebabkan eutrofikasi (blooming alga). Karbon aktif yang dimodifikasi dengan besi oksida dapat digunakan untuk mengurangi jumlah ion tripolifosfat. Karbon aktif dibuat dengan memanfaatkan limbah lindi hitam hasil samping produksi bioetanol. Preparasi komposit karbon aktif/besi oksida dilakukan dengan menambahkan larutan besi dari FeSO4.7H2O ke dalam karbon aktif. Hasil karakterisasi menggunakan difraksi sinar-X menunjukan bahwa besi oksida yang terbentuk pada komposit karbon aktif/besi oksida merupakan fase goethite (α-FeOOH) dan berdasarkan data EDX jumlah kandungan besi yang terdapat pada kompossit karbon aktif/besi oksida adalah 17%. Kinerja komposit karbon aktif/besi oksida terhadap adsorpsi ion tripolifosfat dievaluasi berdasarkan uji variasi konsentrasi larutan awal tripolifosfat, pH, kecepatan agitasi dan waktu kontak. Persentase efisiensi maksimum ion tripolifosfat mencapai 96,87% dengan kapasitas adsorpsinya 1,5992 mg/g pada pH 3, konsentrasi awal larutan tripolifosfat 3 mg/L dan dosis adsorben 0,1 g. Hasil tersebut menunjukan bahwa karbon aktif yang dikompositkan dengan besi oksida memiliki efektifitas dan efisiensi yang tinggi untuk menurunkan ion tripolifosfat. Pada penelitian ini juga dilakukan desorpsi fosfat menggunakan medium asam sulfat, asam sitrat dan akuades. Jumlah fosfat yang terdesorpsi lebih besar dalam medium asam sulfat dengan persentase desorpsinya sebesar 87,71% selama 9 jam.

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Tripolyphosphate ion, known as P3O10-5, is one of phosphate forms which mostly recognized in the laundry wastewater. The abundant quantities of trpolyphosphate ions in the water resources potentially lead eutrophication or algae blooming therefore it damaged the inside-living organisms. To mitigate excess ion, activated carbon was modified with iron oxide can be used to remove the amount of tripolyphosphate ions. Activated carbon was made by utilizing black liquor waste water from bioethanol side-production. Activated carbon/iron oxide composites were prepared by introducing activated carbon into iron solution made from FeSO4.7H2.

The result from X-ray diffraction characterization showed the main iron oxide actually present in the composites was goethite (α-FeOOH) and based on the result of SEM-EDX measurement it contained 17% of iron element. The performance of activated carbon/iron oxide composites on the adsorption of tripolyphosphate ions was evaluated by various initial concentrations of tripolyphosphate solutions, which were adsorbent dose, pH, mixing speed, and contact time. The maximum efficiency percentage of tripolyphosphate ions reached 96.87% with adsorption capacity of 1,5992 mg/g at an initial tripolyphosphate concentration of 3 mg/L, solution pH of 3 and 0,1 g of adsorbent dose.

The results indicated that activated carbon/iron oxide were more effective to decrease tripolyphosphate ions than only activated carbons. This study also conducts desorption experiments of phosphate on sulfuric acid, citric acid, and aquades solutions. Amount of phosphate desorption in sulfuric acid medium was the highest desorption percentage around 87,717% within 9 hours."

"This paper presents an investigation on the method for synthesizing hematite nanoparticle using ultrasonic sonochemistry. The effect of various bases with different basicity strengths, i.e. NaOH, NH4OH, and butylamine, as well as sintering treatment on the purity and crystallinity of hematite nanoparticles was studied. In this work, the as-synthesized hematite nanoparticles were characterized using FTIR, XRD, and HR-TEM analyses. The results showed that the formation of hematite crystal can undergo two possible reaction pathways depending on the basicity of the solution. When strong bases like NaOH and butylamine were used, iron(III) ion could react with water to form iron complexes, which further grow into rod-like magnetite nanocrystals as the major product. However, direct reaction of iron(III) ion with hydroxide ion to form hematite was observed when a weak base like NH4OH was used. Furthermore, it was also found that most of the polymorphous iron oxide precursors can be transformed into hematite crystals via high-temperature sintering."

"Superparamagnetic Iron Oxide Nanoparticles (SPION) adalah partikel yang terbuat dari kristal besi oksida yang memiliki ukuran dalam skala nanometer. Dengan memiliki sifat magnetis dan ukuran yang kecil membuat SPION banyak digunakan untuk berbagai aplikasi medis, seperti sebagai agen diagnosis pada MRI dan agen penghantar obat. Metode kopresipitasi merupakan metode sintesis SPION yang paling banyak digunakan karena memiliki prosedur yang sederhana, ekonomis, dan efisien. Namun, karakteristik SPION yang dihasilkan sulit diatur, khususnya distribusi ukuran partikel. Hal ini dapat diatasi dengan mengatur kondisi sintesis serta melakukan optimasi terlebih dahulu sebelum membuat SPION dalam skala besar. Penelitian ini bertujuan untuk memperoleh kondisi sintesis SPION yang optimal menggunakan metode kopresipitasi serta mengetahui karakteristik SPION yang dihasilkan. Pada penelitian ini dilakukan optimasi suhu pemanasan tambahan dan durasi pengadukan pada proses pembuatan SPION menggunakan metode kopresipitasi. Hasil SPION dikarakterisasi menggunakan Particle Size Analyzer (PSA), X-Ray Diffraction (XRD), dan Transmission Electron Microscopy (TEM) untuk memperoleh data ukuran partikel, distribusi ukuran partikel, indeks polidispersitas, potensial zeta, morfologi, dan kristalinitas. SPION optimal diperoleh menggunakan metode kopresipitasi dengan penambahan pemanasan dengan suhu 120°C dan durasi pengadukan selama 45 menit. SPION optimal memiliki ukuran hidrodinamis partikel 230,5 ± 19,09 nm, ukuran partikel 128,601 ± 30,76 nm, dengan inti kristal berukuran 12,36 nm, PDI 0,807 ± 0,01, dan potensial zeta -23,9 ± 0,14.

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Superparamagnetic Iron Oxide Nanoparticles (SPIONs) are nanometer-sized particles made of iron oxide crystals. Due to their magnetic properties and small size, SPIONs are widely used for various medical applications, such as diagnostic agents in MRI and drug delivery agents. The coprecipitation method is the most widely used SPIONs synthesis method because it has a simple, economical, and efficient procedure. However, the characteristics of the resulting SPIONs are difficult to regulate, especially the particle size distribution. This can be overcome by setting the synthesis conditions and optimizing them before producing SPIONs on a large scale. This study aims to obtain optimal SPIONs synthesis conditions using the coprecipitation method and to determine the characteristics of the resulting SPIONs. In this research, optimization of additional heating temperature and stirring duration was carried out in the process of making SPIONs using the coprecipitation method. SPIONs were characterized using Particle Size Analyzer (PSA), X-Ray Diffraction (XRD), and Transmission Electron Microscopy (TEM) to obtain data on particle size, particle size distribution, polydispersity index, zeta potential, morphology, and crystallinity. Optimal SPIONs were obtained using the coprecipitation method with addition of heating at a temperature of 120°C and a stirring duration of 45 minutes. The optimal SPIONs have a hydrodynamic particle size of 230.5 ± 19.09 nm, particle size of 128,601 ± 30,76 nm, with a crystal core measuring 12.36 nm, PDI 0,807 ± 0.01, and a zeta potential of -23.9 ± 0.14.

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"Bentonit asal Merangin Jambi telah dimodifikasi menjadi komposit magnet bentonit dengan menggunakan prekursor garam besi dalam suspensi bentonit melalui proses pertukaran ion dan presipitasi. Komposit dibuat dengan memvariasikan perbandingan berat bentonit dengan oksida besi dan perbandingan mol Fe(III) dengan Fe(II). Komposit yang dibuat dengan Fe(III) dan Fe(II) bersifat ferimagnetik sedangkan komposit yang dibuat dari Fe(III) dan Fe(II) saja bersifat antiferomagnetik. Produk hasil modifikasi dikarakterisasi dengan X Ray diffraction (XRD), Atomic Absorbtion Spectroscopy (AAS), Scanning Electron Microscope-Energy Dispersive X ray Spectroscopy (SEM-EDS), Vibrating Sample Magnetometer (VSM) and Ultraviolet Visible (UV-Vis). Komposit magnet dengan daya serap terhadap logam Cd(II) tertinggi dengan komposisi bentonit dan oksida besi 2 : 1 dan perbandingan Fe(III) dengan Fe(II) 2 : 1 sedangkan komposit dengan sifat kemagnetan terbesar dengan komposisi 1 : 2 antara bentonit dan oksida besi dan 1 : 1 antara Fe(III) dan Fe(II). Pemberian gelombang ultrasonik setelah terbentuknya oksida besi belum berpengaruh secara signifikan terhadap peningkatan daya adsorpsi dan sifat kemagnetan komposit. Komposit yang telah menyerap logam Cd(II) dapat terambil kembali sebanyak 85,69% dan dapat diregenerasi menggunakan NaCl dengan kemampuan regenerasi 39,61%.

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Bentonite from Merangin Jambi has been modified into a composite magnetic bentonite using an iron salt precursors in a bentonite suspension through a process of ion exchange and precipitation. Composites was made by varying the weight ratio of bentonite with iron oxide and the mole ratio of Fe (III) to Fe (II). Composites made with Fe(III) and Fe(II) are ferrimagnetic while the composite prepared from Fe (III) or Fe (II) alone is antiferromagnetic. Modification products were characterized using X Ray diffraction (XRD), Atomic Absorbtion Spectroscopy (AAS), Scanning Electron Microscope-Energy Dispersive X ray Spectroscopy (SEM-EDS), Vibrating Sample Magnetometer (VSM) and Ultraviolet Visible (UV-Vis). The highest Cd(II) adsorption from aqueous solution is given by magnetic composite prepared from bentonite to iron oxide ratio of 2: 1 and the ratio of Fe(III) to Fe(II) 2: 1. On the other hand, the composite with the highest magnetic properties is provided from the preparation using the ratio of 1:2. between bentonite and iron oxides, and ratio of 1: 1 between Fe(III) and Fe(II). The ultrasonic treatment to the mixture after iron oxide was formed showed no significant effect to the increase of adsorption and magnetic properties. The composite that has been adsorb Cd(II) ions can be drawn back as much as 85.69% and can be regenerated using NaCl with regeneration ability to 39.61%."

"Penyakit ginjal kronis (PGK) merupakan salah satu penyakit dengan tingkat kematian terbanyak di dunia. Oleh karena itu, diperlukan metode diagnosis yang cekatan dan akurat agar dapat ditangani dalam waktu secepatnya. Magnetic Particle Imaging (MPI) adalah metode pencitraan non-invasif baru yang sedang berkembang. MPI bekerja dengan menggunakan medan magnet untuk memindai, mengeksitasi dan mendeteksi sinyal tracer, yang berupa superparamagnetic iron oxide nanoparticle (SPION), yang sebelumnya telah diinjeksikan ke dalam subjek. Dibandingkan dengan modalitas lain seperti Computed Tomography (CT), tracer MPI tidak radioaktif dan tidak diproses oleh ginjal, sehingga lebih aman untuk diagnosis atau pemantauan PGK. Tujuan dari penelitian tesis ini adalah untuk menyimulasikan alat MPI dengan bidang field-free point (FFP) dan mendemonstrasikan rekonstruksi citra MPI 1D dari sinyal output simulasi. Hal tersebut dilakukan dengan membuat model 3 dimensi sesuai dengan parameter yang telah ditentukan oleh hasil studi literatur dan melakukan simulasi dengan tracer pada lokasi-lokasi berbeda dalam field of view, lalu mengolah data menggunakan dua metode signal processing yaitu metode system matrix (SM) dan metode X-Space. Hasil dari penelitian adalah model 3D mampu menyimulasikan kinerja MPI dengan cukup baik, dengan hasil rekonstruksi dengan metode SM mempunyai error rata-rata 42,66% dan skor Structural Similarity Index Measure (SSIM) 0,346 karena jumlah sampel yang sedikit. Namun, sinyal output tidak dapat digunakan untuk rekonstruksi X-Space oleh karena bentuk FFP yang terlalu landai, meskipun berdasarkan pemodelan matematis, metode rekonstruksi X-Space memiliki tingkat akurasi yang sangat tinggi dengan waktu rekonstruksi yang cepat, dengan resolusi 2 mm dan skor SSIM 0,861. Melalui penelitian ini, didapat bahwa meskipun tidak dapat menggunakan metode X-Space, model MPI yang dibuat mampu digunakan untuk menyimulasikan kinerja MPI FFP 1D dengan akurasi yang cukup baik agar dapat menghasilkan citra melalui metode rekonstruksi system matrix.

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Chronic kidney disease (CKD) is one of the deadliest diseases in the world. Therefore, there is a constant search for an accurate and fast method to diagnose CKD so treatment can begin as fast as possible. Magnetic Particle Imaging (MPI) is an emerging non-invasive imaging method that is currently being developed for medical use. MPI uses a combination of varying magnetic fields to scan and detect magnetic signals from its tracers, named superparamagnetic iron oxide nanoparticles (SPIONs), which are injected into the subject beforehand. Compared to other imaging modalities like Computed Tomography (CT), MPI’s tracers are not radioactive and are not processed in the kidneys, making it a safer option for diagnosing CKD without worsening its condition. The aim of this thesis is to simulate the mechanisms of a field-free point (FFP) MPI and to reconstruct a 1D image based on the acquired simulated MPI data. This is done by making a 3-dimensional model of an MPI device based on parameters gathered via literature research and simulating MPI scans with tracers located in various points inside the field of view. The gathered data are then processed by two methods, the system matrix (SM)-based reconstruction and the X-Space reconstruction. The results of this research are that the 3D model can simulate the mechanisms of MPI properly, with an average error of 42.66% and a Structural Similarity Image Measure (SSIM) score of 0.346 using the SM-based reconstruction due to a very limited sample size and an inaccurate tracer model. However, the signals cannot be reconstructed using X-Space methods due to the low gradient of the FFP, despite the X-Space method being a very fast and accurate reconstruction method based on mathematical models, having a 2 mm resolution and an SSIM of 0.861. These findings conclude that despite being unable to use the X-Space reconstruction method, the 1-dimensional FFP MPI model can simulate the mechanics of MPI with enough accuracy to create an image using SM-based reconstruction."

"Doksorubisin (DOX) merupakan agen kemoterapi antrasiklin yang bekerja dengan memperlambat atau menghentikan pertumbuhan sel kanker. Namun, penggunaan DOX memiliki efek toksik pada sel normal serta efek samping kardiotoksisitas. Penelitian ini bertujuan membuat sistem penghantaran DOX dengan SPION-PAMAM-HA, mengkarakterisasi, dan mengevaluasi konjugat superparamagnetic iron oxyde nanoparticle-poliamidoamin G4-asam hialuronat-doksorubisin (SPION-PAMAM-HA-DOX). Hasil karakterisasi SPION-TC menunjukkan kristal magnetit dengan ukuran 2,79 nm. Konjugat SPION-PAMAM-HA-DOX menunjukkan diameter rata-rata 292,57 ± 4,86 nm, indeks polidispersitas 0,216 ± 0,002 nm, dan nilai zeta potensial -53,37 ± 3,68 mV. Studi pelepasan pada 10 jam dapat terlihat bahwa sebanyak 99% doksorubisin dilepaskan di lingkungan pH 5, sementara kurang dari 10% doksorubisin dilepaskan di lingkungan pH 7,4. Uji sitoksisitas menunjukkan konjugat SPION-PAMAM-HA-DOX memiliki efek toksik pada sel HeLa dan sel Vero dengan IC50 2,54 ± 0,27 µM pada sel HeLa dan CC50 2,18 ± 0,019 µM pada sel Vero serta memiliki nilai SI SPION-PAMAM-HA-DOX lebih besar dibandingkan SI DOX yang menandakan bahwa konjugat SPION-PAMAM-HA-DOX masih aman digunakan dan masih memiliki efek anti kanker.

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Doxorubicin (DOX) is an anthracycline chemotherapy agent that works by slowing or stopping the growth of cancer cells. However, DOX has a toxic effect on normal cells as well as a side effect of cardiotoxicity. This study aims to develop a DOX delivery system with SPION-PAMAM-HA, characterize, and evaluate of superparamagnetic iron oxide nanoparticle-polyamidoamine G4-hyaluronic aciddoxorubicin (SPION-PAMAM-HA-DOX). Superparamagnetic iron oxide nanoparticle (SPION) could be used as diagnostic agent, polyamidoamine G4 (PAMAM) was used as carrier and hyaluronic acid (HA) was used as active targeting moiety. SPION were prepared by co-precipitation method, then SPION-PAMAM-HA-DOX were produced by conjugation of SPION with PAMAM-HA and DOX. SPION-PAMAM-HA-DOX were characterized by particle size analyzer (PSA), UV-Vis spectrophotometry, fourier transform infrared spectroscopy (FTIR), fluorescence spectrophotometry, and transmission electron microscopy (TEM). The release study was conducted by using pH 5 and pH 7.4. Cytotoxicity study was conducted on HeLa cells and Vero cells by using MTT [3-(4,5-Dimethylthiazole-2-yl)-2,5-diphenyltetrazolium bromide] assay. The characterization results of SPION-TC showed magnetite crystals with a size of 2.79 nm. The mean particle size, polydispersity index, and zeta potential of SPION-PAMAM-HADOX were 57 ± 4.86 nm, 0.216 ± 0.002 nm, and -53.37 ± 3.68 mV. The release study at 10 hours showed that 99% of DOX was released in pH 5, while less than 10% DOX was released in pH 7.4. The cytotoxicity study showed that SPION-PAMAM-HA-DOX has toxicity effect on HeLa cells and Vero cells with IC50 2,54 ± 0,27 µM on HeLa cells, CC50 2,18 ± 0,019 µM on Vero cells sel Vero, and SI value of SPION-PAMAM-HA-DOX greater than SI DOX which indicates that SPION-PAMAM-HA-DOX conjugate is still safe to use and has anti-cancer effects"