UNESA Journal of Chemistry最新文献

{"title":"PENGARUH JUMLAH CROSSLINKER TERHADAP PERSEN EKSTRAKSI PADA SINTESIS MOLECULARLY IMPRINTED POLYMER SEBAGAI ADSORBEN UNTUK KLORAMFENIKOL THE EFFECT OF CROSSLINKER AMOUNT TO THE PERCENT EXTRACTION IN MOLECULARLY IMPRINTED POLYMER SYNTHESIS AS AN ADSORBEN","authors":"Neli Kartika Asni, Maria Monica Sianita","doi":"10.26740/ujc.v9n3.p179-188","DOIUrl":"https://doi.org/10.26740/ujc.v9n3.p179-188","url":null,"abstract":"Kloramfenikol (CAP) adalah salah satu antibiotik yang sering digunakan karena berspektrum luas dan ketersediaannya yang mudah, tetapi dalam penggunaan jangka panjang dapat meninggalkan residu pada jaringan atau organ bahkan suatu produk makanan. Residu yang tertinggal dalam konsentrasi rendah memerlukan teknik pemekatan yang sesuai sebelum dianalisis menggunakan instrument High-Performance Liquid Chromatography. Salah satu teknik pemekatan yang dapat digunakan untuk menganalisis sampel berkonsentrasi rendah adalah menggunakan MIP (Molecularly Imprinted Polymer). MIP disintesis melalui polimerisasi template, monomer, dan crosslinker dengan suatu porogen. Dalam penelitian ini digunakan variasi jumlah mol ethylene glycol dimethacrylate (EGDMA) sebagai crosslinker dengan CAP sebagai template, asam metakrilat (MAA) sebagai monomer, dan asetonitril sebagai porogen menggunakan metode presipitasi serta dilakukan karakterisasi menggunakan instrumen FT-IR. Tujuan dari penelitian ini adalah untuk mengetahui pengaruh dan komposisi terbaik dari jumlah EGDMA terhadap persen ekstraksi serta menganalisis keberadaan gugus NO2 dari polimer terbaik yang dikarakterisasi menggunakan instrumen FT-IR. Hasil penelitian menunjukkan bahwa jumlah mol crosslinker mempengaruhi persen ekstraksi dan komposisi terbaik antara CAP:MAA:EGDMA yaitu 1:3:18 yang menghasilkan persen ekstraksi paling tinggi yaitu 67,14%. Dari hasil karakterisasi FT-IR menunjukkan bahwa MIP masih mengandung CAP ditandai dengan munculnya serapan gugus –NO2 yang tidak tajam pada bilangan gelombang 1357,07 cm-1. Serapan gugus –NO2 pada NIP (Non Imprinted Polymer)terlihat tajam pada bilangan gelombang 1520,30 cm-1 dan 1377,76 cm-1serta spektra PB (Polimer Blanko) tidak terdapat serapan gugus –NO2 karena tidak mengandung kloramfenikol. \u0000  \u0000Kata kunci : Kloramfenikol, Molecularly Imprinted Polymer, metode presipitasi \u0000  \u0000Chloramphenicol (CAP) is one of antibiotics that’s often be used because of its broad spectrum and easy availability, but in long-term use it can leave residue in tissues or organs and even on a food product. Residues left in low concentrations require an appropriate preconcentration technique before being analyzed using the High Performance Liquid Chromatography  instrument. One of preconcentration technique that can be used is using MIP (Molecularly Imprinted Polymer). MIP is synthesized through polymerization of templates, monomers, and crosslinkers with a porogen. This research used variations in the number of moles of ethylene glycol dimethacrylate (EGDMA) as a crosslinker with CAP as a template, methacrylic acid (MAA) as a monomer, and acetonitrile as porogen using the precipitation method and characterization using FT-IR instruments. The purpose of this research was to determine the effect and the best composition of the amount of EGDMA to the percent extraction and analyze the presence of –NO2 groups of the best polymers that were characterized using FT-IR instruments. The results sho","PeriodicalId":53369,"journal":{"name":"UNESA Journal of Chemistry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42429315","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"PENGARUH VARIASI pH TERHADAP PENGUKURAN ASAM OKSALAT DENGAN ELEKTRODA GRAPHENE OXIDE TERMODIFIKASI NANOBENTONIT SECARA SIKLIK VOLTAMETRI THE EFFECT OF VARIOUS pH VALUES ON MEASUREMENT OXALIC ACID USING NANOBENTONITE MODIFIED GRAPHENE OXIDE ELECTRODE BY CY","authors":"Pirim Setiarso, Eka Candra Saputra","doi":"10.26740/ujc.v9n3.p197-202","DOIUrl":"https://doi.org/10.26740/ujc.v9n3.p197-202","url":null,"abstract":"Telah dipelajari pengaruh pH pada pengukuran asam oksalat menggunakan elektroda Graphene oxide termodifikasi nanobentonit dengan metode siklik voltametri.Graphene oxide dan nanobentonitmasing-masing telah berhasil disintesis metode Improved Hummer dan Sonochemical. Elektroda dibuat dari campuran Graphene oxide:nanobentonit:parafin dengan perbandingan 3:2:5; 3:3:4; 3:4:3; 3:5:2. Variasi pH yang dipelajari yaitu 3,5; 4; 4,5; 5; dan 5,5. Kedua material tersebut di karakterisasi dengan FTIR dan PSA. Spektrum FTIR Graphene oxide membuktikan bahwa Graphene oxide telah berhasil disintesis dengan memunculkan gugus –OH pada bilangan gelombang3445cm-1., tekukan C=C pada bilangan gelombang1622cm-1, regangan gugus C-O pada bilangan gelombang 1225cm-1 dan regangan gugus epoksi C-O-C pada bilangan gelombang 1042cm-1. Spektrum FTIR nanobentonit menunjukkan serapan kuat pada bilangan gelombang 1028cm-1 menunjukkan regangan gugus Si-O-Si, pada bilangan gelombang 793 cm-1 menunjukkan regangan gugus Al-O-Si. Sementara data PSA menunjukan bahwa distribusi partikel graphene oxide sebanyak 5% berukuran 0,61μm. Data PSA menunjukkan bahwa distribusi partikel nanobentonit sebanyak 5 % berukuran 1.09μm. Hasil penentuan elektroda komposisi terbaik yaitu pada perbandingan komposisi 3:5:2 dengan arus puncak anodik sebesar 3,29x10-3 A. Pengukuran asam oksalat terbaik pada kondisi pH larutan 4,5 dengan arus puncak anodik sebesar 3,76x10-3 A.Kata kunci : voltametri siklik, elektroda Graphene oxide termodifikasi nanobentonit, asam oksalat \u0000The effect of pH on the measurement of oxalic acid using nanobentonite modified Graphene oxide electrodes with the cyclic voltammetry method. Graphene oxide and nanobentonite have been successfully synthesized by the Improved Hummer and Sonochemical methods. Electrodes are made from a mixture of Graphene oxide: nanobentonite: paraffin in a ratio of 3:2:5; 3:3:4; 3:4:3; 3:5:2. The pH variations studied were 3.5; 4; 4,5; 5; and 5.5. Both materials were characterized by FTIR and PSA. The FTIR spectrum of Graphene oxide proves that Graphene oxide has been successfully synthesized by raising the -OH group at wave number 3445cm-1. bend C=C at wave number 1622cm-1, the strain of C-O group at wave number 1225cm-1, and strain of epoxy group C-O-C at wave number 1042cm-1. The nanobentonite FTIR spectrum shows strong absorption at wave number 1028cm-1 indicating strain of the Si-O-Si group, at wave number 793 cm-1 indicating the strain of the Al-O-Si group. While the PSA data show that the distribution of graphene oxide particles as much as 5% measuring 0.61μm. PSA data show that the distribution of 5% nanobentonite particles is 1.09μm. The results of the determination of the best composition electrode are at a ratio of 3:5:2 with an anodic peak current of 3.29x10-3 A. The best measurement of oxalic acid at the pH of the solution 4.5 with an anodic peak current of 3.76x10-3 A.Key words: cyvlic voltammetry, nanobentonite modified Graphene oxide electrode,","PeriodicalId":53369,"journal":{"name":"UNESA Journal of Chemistry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47988711","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"PENGARUH VARIASI KONSENTRASI AMILASE DARI KEDELAI (Glycine max L.) DAN NATRIUM ALGINAT SEBAGAI MATRIKS ENZIM TERHADAP EFEKTIVITAS IMOBILISASI THE EFFECT OF AMYLASE CONCENTRATION VARIATION FROM SOYBEAN (Glycine max L.) AND SODIUM ALGINATE AS ENZYME MATRIX","authors":"Tirsa Fitriana Angsari, Rudiana Agustini","doi":"10.26740/ujc.v9n3.p203-211","DOIUrl":"https://doi.org/10.26740/ujc.v9n3.p203-211","url":null,"abstract":"Produksi enzim dalam bentuk murni memerlukan biaya yang cukup tinggi, sehingga diperlukan alternatif dengan memanfaatkan sumber daya alam. Kecambah kacang kedelai adalah salah satu yang berpotensi sebagai sumber enzim amilase. Analisis saat ini yang melibatkan enzim amilase bebas memiliki kelemahan diantaranya hanya dapat digunakan sekali pakai, secara teknis sangat sulit untuk memisahkan enzim dan produk, sulit mendapatkan kembali enzim yang masih aktif di akhir reaksi. Solusi untuk mengatasi kelemahan penggunaan enzim ialah dengan menggunakan teknologi imobilisasi enzim. Penelitian ini bertujuan untuk mengetahui pengaruh variasi konsentrasi amilase dari kacang kedelai (Glycine max L.) dan natrium alginat sebagai kisi matriks penyalut enzim terhadap efektivitas imobilisasi. Hasil penelitian menunjukkan bahwa konsentrasi amilase dan Na-alginat mempengaruhi efektivitas imobilisasi. Diperoleh kondisi optimum imobilisasi amilase pada konsentrasi amilase 10% dan konsentrasi Na-alginat 5% dengan jumlah enzim terimobilisasi sebanyak 2,2453 mg/mL dan nilai persentase efektivitas sebesar 98,1653%. Aktivitas sisa penggunaan berulang amilase imobil hingga 6 kali dengan aktivitas sisa sebesar 50,7788%.Kata kunci : kedelai, amilase, imobilisasi, Na-alginat \u0000The production of enzymes in pure form requires a high enough cost so that alternatives are needed by utilizing natural resources. Soybean sprouts are a potential source of amylase enzymes. The current analysis involving free amylase enzymes has a disadvantage including that it can only be used once, technically it is very difficult to separate enzymes and products, it is difficult to recover enzymes that are still active at the end of the reaction. The solution to overcome the disadvantages of using enzymes is to use enzyme immobilization technology. This study aims to determine the effect of variations in the amylase concentration of soybeans (Glycine max L.) and sodium alginate as an enzyme coating matrix on the effectiveness of immobilization. The results showed that the concentration of amylase and Na-alginate influenced the effectiveness of immobilization. The optimum conditions for amylase immobilization were obtained at 10% amylase concentration and 5% Na-alginate concentration with the amount of immobilized enzyme as much as 2.2453 mg / mL and the percentage of effectiveness was 98.1653%. Residual activity of repeated use of immobilized amylase up to 6 times with residual activity of 50.7788%.Key words: soybeans, amylase, immobilization, Na-alginate","PeriodicalId":53369,"journal":{"name":"UNESA Journal of Chemistry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41925198","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"PEMBUATAN ELEKTRODA KERJA GRAPHENE OXIDE TERMODIFIKASI NANO BENTONIT UNTUK ANALISIS ASAM NIKOTINAT SECARA VOLTAMETRI SIKLIK MAKING OF GRAPHENE OXIDE NANO BENTONITE MODIFIED WORKING ELECTRODE FOR ANALYSIS NICOTINIC ACID USING CYCLIC VOLTAMMETRY","authors":"Nerry Puspita Sari, Pirim Setiarso","doi":"10.26740/ujc.v9n3.p170-178","DOIUrl":"https://doi.org/10.26740/ujc.v9n3.p170-178","url":null,"abstract":"Pada penelitian ini telah dilakukan penelitian pengukuran asam nikotinat menggunakan elektroda kerja Graphene oxide termodifikasi nano bentonit dengan metode voltametri siklik. Elektroda kerja Graphene oxide termodifikasi nano bentonit dibuat dengan cara mencampurkan Graphene oxide, parafin, dan nano bentonit dengan perbandingan 3:5:2, 3:4:3, 3:3:4, 3:2:5. Parameter optimasi yang diuji yaitu kondisi optimum (pH, waktu deposisi, dan laju pindai), komposisi modifier nano bentonit yang ditambahkan. Elektroda kerja Graphene oxide termodifikasi nano bentonit pada kondisi pengukuran optimum digunakan untuk menentukan analisis asam nikotinat secara voltametri siklik. Hasil penelitian menunjukkan komposisi terbaik diperoleh 3:3:4 dengan nilai puncak katodik -0.00375A. pH optimum diperoleh 5 dengan nilai puncak katodik -0.00337A. Waktu deposisi optimum diperoleh selama 5 detik dengan nilai puncak katodik -0.00144A dan laju pindai optimum diperoleh 100 mV/detik dengan nilai puncak katodik -0.00272A. Perbandingan persen perolehan kembali asam nikotinat secara voltametri siklik dengan elektroda kerja Graphene oxide termodifikasi nano bentonit lebih besar yaitu 96.164% dibandingkan dengan metode HPLC adalah 88.332%.Kata kunci : graphene oxide, nano bentonit, asam nikotinat, voltametri siklik \u0000In this research modified Graphene oxide electrode with nano bentonite has been prepared, for determination of nicotinic acid using cyclic voltammetry. Graphene oxide electrode modified by nano bentonite was made by with mixing Graphene oxide, paraffin, and nano bentonite with 3:5:2, 3:4:3, 3:3:4, 3:2:5. The observed parameters includes pH, deposition time, scan rate at modified Graphene oxide electrode with nano bentonite, and composition of modifier in modified Graphene oxide Graphene oxide electrode with nano bentonite. The results showed the best composition obtained 3:3:4 with an peak of cathodic value of -0.00375A. The optimum pH obtained 5 with an peak of cathodic value of -0.00337A.The optimal deposition time obtained for 5 seconds with an peak of cathodic value of -0.00144A and optimal scanning rate obtained 100 mV/second with an peak of cathodic value -0.00272A. Comparison of the results of nicotinic acid recovery using Graphene oxide nano bentonite modified electrode using the cyclic voltammetry method is greater that is 96.164% compared to the method HPLC is 88.332%.Key words: graphene oxide, nano bentonite, nicotinic acid, cyclic voltammetry","PeriodicalId":53369,"journal":{"name":"UNESA Journal of Chemistry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47135737","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}