Jurnal Kimia Valensi最新文献

{"title":"Sintesis Dan Karakterisasi Kompleks Brazilin dari Ekstrak Kayu Secang (Caesalpinia sappan Linn) Serta Aplikasinya dalam Dye Sensitized Solar Cells (DSSC)","authors":"Zulenda Zulenda, U. A. Naselia, Nico Gustian, T. A. Zaharah, Winda Rahmalia","doi":"10.15408/JKV.V5I1.8559","DOIUrl":"https://doi.org/10.15408/JKV.V5I1.8559","url":null,"abstract":"Secang (Caesalpinia sappan Linn) merupakan tanaman endemik Kalimantan Barat yang mengandung pigmen berwarna merah brazilin. Dalam penelitian ini, brazilin diperoleh melalui proses maserasi dilanjutkan dengan partisi cair-cair, selanjutnya dikomplekskan dengan ion logam Cu, Mg, dan Zn untuk meningkatkan kinerjanya ketika digunakan sebagai sensitizer pada dye sensitized solar cell (DSSC). Pengompleksan dilakukan menggunakan media gliserol-air, sedangkan fabrikasi DSSC dilakukan menggunakan metode doctor blading. Hasil analisis FTIR terhadap ekstrak kayu secang menunjukkan adanya gugus fungsi O-H, C=O, C=C, dan C-H, yang merupakan gugus fungsional khas dari brazilin. Terbentuknya kompleks brazilin-Cu, brazilin-Mg, dan brazilin-Zn ditandai dengan menurunnya intensitas puncak dari C=O pada 1606 cm-1 dan –OH pada 3263 cm-1. Hasil analisis UV-Vis menunjukkan bahwa kompleks memiliki rentang panjang gelombang lebih lebar dan cenderung batokromik. DSSC yang menggunakan kompleks brazilin-Cu, brazilin-Mg, dan brazilin-Zn menghasilkan rendemen konversi energi maksimum pada 200 W/m2, berturut-turut sebesar 0.034 %, 0.030 %, dan 0.013 %, serta DSSC ekstrak kayu secang murni sebesar 0.029 %. Dengan demikian, penggunaan sensitizer berbasis kompleks logam-brazilin dapat meningkatkan efisiensi DSSC. Kata kunci: Brazilin, DSSC, fotosensitizer, kayu secang, kompleks. Secang (Caesalpinia sappan Linn) is an endemic plant in West Kalimantan that contains Brazilin red pigments. In this study, brazilin was obtained through a maceration process carried out by a liquid-liquid partition, then complexed with metal ions to improve the performance of compilation used as a sensitizer on dye-sensitized solar cell (DSSC). Complexation is carried out using glycerol-water media, while DSSC fabrication is carried out using the doctor blading method. The results of FTIR analysis of secang wood extract showed the presence of a functional group O-H,  C=O, C=C, and C-H, which are typical functional groups of brazilin. The formation of the brazilin-Cu, brazilin-Mg, and brazilin-Zn complexes is characterized by an increase in peak intensity of  C=O at 1606 cm-1 and O-H at 3263 cm-1. The results of the UV-Vis analysis show that the complex has a wider wavelength and uses batochromic. DSSCs that use the brazilin-Cu, brazilin-Mg, and brazilin-Zn complexes that complement each other produce efficiencies of  0.034%, 0.030%, and 0.013%, and DSSC pure secang wood extract of  0.029%. The efficiency of the brazilian metal-complex when compared with brazilin, the efficiency increases, so that the maximum efficiency obtained by the Cu-brazilin sensitizer is equal to 0.034%. Keywords: Brazilin, DSSC, photosensitizer, secang wood, complex.","PeriodicalId":17786,"journal":{"name":"Jurnal Kimia Valensi","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48281911","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":"Kemampuan Kerang Hijau (Perna viridis) Mengakumulasi Plutonium Melalui Jalur Air Laut","authors":"B. Budiawan, Nur Hidayati Febriana, H. Suseno","doi":"10.15408/JKV.V5I1.7730","DOIUrl":"https://doi.org/10.15408/JKV.V5I1.7730","url":null,"abstract":"Operasional fasilitas nuklir yang ada di Serpong memungkinkan melepas radionuklida ke lingkungan. Isotop Pu merupakan radionuklida yang terlepas ke lingkungan. Lepasan tersebut terbawa oleh air sungai atau run off memasuki Teluk Jakarta. Kerang hijau (Perna viridis) mampu mengakumulasi radionuklida tersebut. Studi ini bertujuan untuk memahami kinetika proses bioakumulasi Pu oleh kerang hijau yang dipengaruhi oleh spesiasinya. Percobaan dilakukan melalui tahapan: aklimatisasi, bioakumulasi (242Pu3+ dan 242Pu4+) dan depurasi. Parameter biokinetika diamati meliputi faktor konsentrasi (CF), konstanta laju pengambilan (ku), konstanta laju pelepasan (ke), faktor biokonsentrasi (BCF), dan waktu paruh biologis (tb1/2). Berdasarkan uji statis non parametric menunjukkan spesiasi 242Pu3+ dan 242Pu4+ berpengaruh terhadap kemampuan Perna viridis mengakumulasi Pu.  Rerata kemampuan bioakumulasi 242Pu4+  oleh Perna viridis adalah 1,2 kali dibandingkan 242Pu4+. Kata kunci : Bioakumulasi , biokinetika,  Perna viridis, plutonium,  spesiasi,  Perna viridis, plutonium. Operations of nuclear facilities in Serpong have potentially release radionuclides to environment. Pu isotope is one of radionuclide that is released into the environment. The release of this radionuclide was carried by the river water or run off entered the Bay of Jakarta. Green mussels (Perna viridis) can be accumulate this radionuclides. The aims of this study was to understand of the biokinetic of Pu bioaccumulation process by green mussels which are affected by its speciation. The experiment was carried out through stages: acclimatization, bioaccumulation (242Pu3+ and 242Pu4+) and depuration. Biokinetic parameters was observed include concentration factor (CF), uptake rate constant (ku), release rate constant (ke), bioconcentration factor (BCF), and biological half-life (tb1/2). Base on non parametric statistic test shown that speciation of 242Pu3+ and 242Pu4+ had an effect on the ability of Perna viridis to accumulate Pu. Avarage of bioaccumulation capabilities of 242Pu4+ by Perna viridis are 1.2 than 242Pu3+. Keywords: bioaccumulation, biokinetics, plutonium, Perna viridis,  speciation.","PeriodicalId":17786,"journal":{"name":"Jurnal Kimia Valensi","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49175959","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":"Potensi Zeolit Alam Ende-NTT sebagai Katalis Transformasi Senyawa Gula Menjadi 5-Hidroksimetilfurfural (HMF)","authors":"Mela Faradika, S. Sugiarti, Purwatiningsih Sugita","doi":"10.15408/JKV.V1I1.8174","DOIUrl":"https://doi.org/10.15408/JKV.V1I1.8174","url":null,"abstract":"Sintesis 5-hidroksimetilfurfural (HMF) dari senyawa gula (glukosa dan fruktosa) dengan katalis zeolit alam Ende-Nusa Tenggara Timur (NTT) menggunakan pelarut dimetil-sulfoksida (DMSO) dan metode refluks telah dilakukan. Penelitian ini bertujuan untuk melihat efektivitas zeolit alam Ende sebagai katalis transformasi senyawa gula menjadi 5-hidroksimetilfurfural (HMF). Hasil penelitian menunjukkan bahwa zeolit alam Ende tanpa aktivasi dan modifikasi (ZA), zeolit teraktivasi asam (ZAA), zeolit teraktivasi basa (ZAB), Na-zeolit teraktivasi asam (Na-ZAA), Na-zeolit teraktivasi basa (Na-ZAB), H-zeolit teraktivasi asam (H-ZAA), dan        H-zeolit teraktivasi basa (H-ZAB) memiliki potensi sebagai katalis untuk transformasi senyawa gula menjadi HMF. Rendemen yang dihasilkan untuk substrat fruktosa berkisar 43-74%, sedangkan untuk substrat glukosa berkisar 2-12%. ZAA memiliki aktivitas katalitik terbaik sebagai katalis dalam mengkonversi fruktosa menjadi HMF dengan rendemen 74.84%, sedangkan untuk substrat glukosa adalah katalis H-ZAA dengan rendemen sebesar 12.77%. Kata kunci: 5-Hidroksimetilfurfural (HMF), fruktosa, glukosa, katalis, zeolit The synthesis of 5-hydroxymethylfurfural (HMF) from sugars (glucose and fructose) with natural zeolite catalyst of Ende-Nusa Tenggara Timur (NTT) in dimethyl-sulfoxide (DMSO) using reflux method has been done. This study aims to observe the ability of natural zeolite Ende as a catalyst for the transformation of sugar compounds into HMF. According to the research, Ende natural zeolite without activation and modification (ZA), acid activation zeolite (ZAA), alkaline activation zeolite (ZAB), acid activation Na-zeolite (Na-ZAA), alkaline activation Na-zeolite (Na-ZAB), acid activation H-zeolite (H-ZAA) and alkaline activation H-zeolite (H-ZAB) have the ability to transform sugar compounds into HMF. HMF yield for fructose as a substrate was 43-74%, while those for glucose as a substrate was 2-12%. ZAA catalyst had the best catalytic activity as a catalyst in converted fructose to HMF with yield was 74.84%, while for glucose substrate was H-ZAA catalyst with yield was 12.77%. Keywords: 5-Hydroxymethylfurfural (HMF), catalyst, fructose, glucose, zeolite.","PeriodicalId":17786,"journal":{"name":"Jurnal Kimia Valensi","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42313141","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":"Turunan Senyawa Flavonoid dari Daun Macaranga involucrata (Roxb.) Baill dari Buton Tengah, Sulawesi Tenggara","authors":"Edi Ilimu, Yana M. Syah","doi":"10.15408/JKV.V5I1.7909","DOIUrl":"https://doi.org/10.15408/JKV.V5I1.7909","url":null,"abstract":"Macaranga merupakan salah satu genus terbesar dari famili Euphorbiaceae yang terdiri dari 300 spesies dengan nama lokal mahang-mahangan. Tumbuhan Macaranga tersebar luas di wilayah Afrika dan Madagaskar di bagian barat hingga ke wilayah tropis Asia, Australia utara dan kepulauan Pasifik. Di Indonesia tumbuhan Macaranga tersebar di beberapa daerah yaitu daerah Papua, Maluku, Sulawesi, Kalimantan, Sumatera, Bangka, dan Jawa. Kajian fitokimia beberapa spesies Macaranga menunjukan adanya kelompok senyawa fenolik yaitu turunan flavonoid dan stilben, serta turunan terpenoid. Senyawa turunan fenolik tersebut memiliki keunikan dari struktur molekulnya, yaitu adanya subtituen tambahan dari metabolit terpenoid yaitu prenil (C5), geranil (C10), farnesil (C15), dan geranilgeranil (C20). Pada penelitian ini telah dilakukan isolasi metabolit sekunder dari daun M. involucrata (Roxb.) Baill dengan metode maserasi menggunakan pelarut aseton, kemudian dilanjutkan pemisahan dan pemurnian dengan menggunakan kromatografi cair vakum dan kromatografi radial untuk mendapatkan senyawa murni. Penentuan struktur dilakukan berdasarkan analisis data spektrum NMR 1D (1H-NMR dan13C-NMR), NMR 2D (NOESY, TOCSY, HSQC, dan HMBC), dan spektrum massa (MS). Berdasarkan metodologi tersebut, dua senyawa turunan flavon yaitu 5,7,4’-trihidroksi-3’(3-metilbut-2-enil)-3-metoksiflavon (1) dan makarangin (2), telah berhasil diisolasi dari tumbuhan ini. Berdasarkan hasil penelitian tersebut menunjukan daun M. involucrata (Roxb.) Baill yang berasal dari Kabupaten Buton Tengah, Sulawesi Tenggara menghasilkan senyawa fenolik turunan flavonoid. Kata kunci: Euphorbiaceae, Macaranga involucrata (Roxb.) Baill, flavon. Macaranga is one of the largest genera of the family Euphorbiaceae comprising 300 species with local name “mahang-mahangan”. Macaranga is widespread in the region of Africa and the west of Madagascar to the tropical regions of Asia, northern Australia, and the Pacific islands. In Indonesia Macaranga spread in several areas:  Papua, Maluku, Sulawesi, Kalimantan, Sumatra, Bangka, and Java. Phytochemical studies showed the presence of several phenolic compounds such as flavonoids and stilbene derivatives. The phenolic compounds have a unique molecular structure with the addition of some substituents such as prenyl (C5), geranyl (C10), farnesyl (C15), and geranylgeranyl (C20). This research has been conducted on the isolation of secondary metabolites from the leaves of M. involucrata (Roxb.) Baill by maceration method using acetone, followed by separation and purification by using liquid vacuum chromatography and radial chromatography to obtain pure compounds. Determination of the structure is based on data analysis of 1D NMR spectrum (1H-NMR and 13C-NMR), 2D NMR (1H-1HCOSY, NOESY, TOCSY, HSQC, and HMBC), and mass spectra (MS). Based on this methodology, two flavone derivatives 5,7,4'-trihydroxy-3'(3-methylbut-2-enyl)-3-methoxy flavone (1) and macarangin (2), have been isolated from this p","PeriodicalId":17786,"journal":{"name":"Jurnal Kimia Valensi","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44864561","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":"Potensi Antibakteri Ekstrak Metanol dan Senyawa Aromatik dari Buah Wualae (Etlingera elatior)","authors":"S. Sahidin, Syefira Salsabila, W. Wahyuni, Fristiohady Adryan, I. Imran","doi":"10.15408/JKV.V5I1.8658","DOIUrl":"https://doi.org/10.15408/JKV.V5I1.8658","url":null,"abstract":"Buah tanaman wualae (bahasa Tolaki) atau Etlingera elatior digunakan oleh masyarakat Tolaki (Sulawesi Tenggara) sebagai bumbu masak dan obat tradisional. Untuk mengungkap potensi tersebut, khususnya buah wualae, dilakukan kajian fitokimia dan farmakologi buah wualae. Kajian fitokimia meliputi isolasi dan penentuan struktur dikerjakan dengan metode kromatografi (kromatografi vakum cair dan kromatografi radial) dan spektroskopi (1H dan 13C NMR). Kajian farmakologi meliputi uji aktivitas biologi terhadap enam jenis bakteri (Bacillus subtilis FNCC 0060, Escherichia coli ATCC 35218, Pseudomonas aeruginosa ATCC 27853, Salmonella enterica ATCC 14028, Staphylococcus aureus ATCC 25923, dan Streptococcus mutans ATCC 25175). Hasilnya menunjukkan tiga senyawa fenolik telah berhasil diisolasi dan diidentifikasi dari buah wualae yaitu asam vanilat (1), asam p-hidroksibenzoat (2), dan asam kumarat (3). Ketiga senyawa tersebut pertama kali dilaporkan berhasil diisolasi dari buah E. elatior. Aktivitas antibakteri ekstrak metanol buah wualae dan tiga senyawa hasil isolasi menunjukkan bahwa sampel tersebut paling aktif terhadap bakteri S. mutans. Dengan demikian aktivitas senyawa-senyawa hasil isolasi dari buah E. elatior  berkorelasi dengan aktivitas ekstrak metanol buah E. elatior  terhadap S. mutans, dimana senyawa paling aktif adalah asam vanilat. Ekstrak yang dominan mengandung asam vanilat dari tanaman ini dapat dikembangkan sebagai herbal antibakteri S. mutans seperti herbal karies gigi dan obat kumur. Kata kunci: Etlingera elatior, wualae, buah, senyawa aromatik, antibakteri. The fruits of wualae (Tolakinese) or Etlingera elatior is utilized by Tolakinese (Sulawesi Tenggara) as spices and traditional medicine. To reveal the potencies, a study on phytochemical and pharmacological aspects have been carried out. The phytochemical study includes isolation and structure determination used chromatography methods (vacuum liquid chromatography and radial chromatography) and spectroscopy methods (1H NMR and 13C NMR). Biological activity was evaluated against some bacteria that are Bacillus subtilis FNCC 0060, Escherichia coli ATCC 35218, Pseudomonas aeruginosa ATCC 27853, Salmonella enterica ATCC 14028, Staphylococcus aureus ATCC 25923, and Streptococcus mutans ATCC 25175). The results showed that three aromatic compounds had been isolated and identified that are vanillic acid (1), p-hydroxybenzoic acid (2) and coumaric acid (3). All compounds are firstly reported that successfully isolated from fruits of Wualae. Antibacterial potency indicated that the methanol extracts and the isolated compounds are the most active towards S. mutans and have good activity correlation between the extracts and the compounds. Vanillic acid is the most active compound from E. elatior fruits. Thus, the extracts contain dominantly vanillic acid from          E. elatior fruits can be developed to be antibacterial herbals caused by S. mutans. Keywords: Etlingera elatior, wualae, fruits, a","PeriodicalId":17786,"journal":{"name":"Jurnal Kimia Valensi","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48995446","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":"Deteksi Simultan Kuersetin dan Rutin Menggunakan Screen-Printed Carbon Electrode Termodifikasi Grafena","authors":"Tamida Elinda, Wulan Tri Wahyuni, E. Rohaeti","doi":"10.15408/JKV.V5I1.11203","DOIUrl":"https://doi.org/10.15408/JKV.V5I1.11203","url":null,"abstract":"Kuersetin dan rutin merupakan senyawa antioksidan alami yang termasuk golongan flavonoid. Senyawa ini dapat dideteksi dengan beberapa teknik analisis, salah satunya dengan teknik elektrokimia. Pada penelitian ini, deteksi simultan kuersetin dan rutin dilakukan dengan teknik voltametri siklik menggunakan screen printed carbon electrode (SPCE) termodifikasi grafena. Elektrode disiapkan melalui modifikasi elektrode kerja SPCE dengan campuran grafena:natrium poliakrilat (1:1). Larutan etanol 70%:bufer fosfat pH 7 (6:4) digunakan sebagai elektrolit dalam pengukuran kuersetin dan rutin. Hasil penelitian menunjukkan puncak oksidasi kuersetin dan rutin terdeteksi pada potensial 0.179 V dan 0.310 V vs Ag/AgCl. SPCE termodifikasi grafena menghasilkan intensitas arus oksidasi dan sensitivitas yang lebih tinggi pada pengukuran kuersetin dan rutin. Deteksi simultan kuersetin dan rutin menggunakan SPCE termodifikasi grafena menunjukkan linearitas dengan R2 = 0.9905 dan R2 = 0.9816, masing-masing untuk kuersetin dan rutin. Limit deteksi pengukuran kuersetin dan rutin masing-masing sebesar 0.5369 mM dan 0.7495 mM serta limit kuantitasi sebesar 1.7898 mM dan 2.4985 mM. Presisi pengukuran kuersetin dan rutin memiliki nilai simpangan baku relatif (%SBR) sebesar 2.14% dan 2.44%, berturut-turut untuk kuersetin dan rutin. Hal ini menunjukkan bahwa SPCE termodifikasi grafena cukup potensial untuk deteksi simultan kuersetin dan rutin secara elektrokimia. Kata kunci: Grafena, kuersetin, rutin, screen printed carbon electrode, voltametri siklik. Quercetin and rutin are natural antioxidant from flavonoid group. The compounds can be detected using several analytical technique, including electrochemical technique due to its redox activity. In this study, simultaneous detection of quercetin and rutin was performed at graphene-modified screen printed carbon electrode (SPCE) using cyclic voltammetry technique. Graphene-modified SPCE was prepared from mixture of graphene:sodium polyacrylate (1:1) via drop casting method. Ethanol 70%:phosphate bufer pH 7 (6:4) was used as electrolyte solution for quercetin and rutin measurement. The result shows that oxidation peak of quercetin and rutin was detected at potential of 0.179 V and 0.310 V vs Ag/AgCl, respectively. Graphene-modified SPCE produce higher intensity of oxidation current and higher sensitivity for quercetin and rutin measurement. Simultaneous detection of quercetin and rutin at graphene modified SPCE provide linearity with R2 = 0.9905 and R2 = 0.9816, respectively for quercetin and rutin. Detection limits of quercetin and rutin respectively was 0.5369 mM and 0.7495 mM while limit quantitation was 1.7898 mM dan 2.4985 mM. Precision of quercetin and rutin measurement was moderate with percent relative standard deviation (%RSD) of 2.14% and 2.44%, consecutively for quercetin and rutin. This suggests that graphene-modified SPCE is potential for simultaneous electrochemical detection of quercetin and rutin. Keywords: Cyclic vo","PeriodicalId":17786,"journal":{"name":"Jurnal Kimia Valensi","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46419139","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":"Rapid Method for Analyzing Gadolinium Binding Activity using Colorimetric Assay Employing PAR","authors":"Meri Ayurini, Tony Ekkelenkamp, J. Paulusse, J. Engbersen","doi":"10.15408/JKV.V5I1.9238","DOIUrl":"https://doi.org/10.15408/JKV.V5I1.9238","url":null,"abstract":"Pada penelitian ini, kami mempelajari colorimetric assay yang melibatkan 4-(2-pyridilazo)-resorcinol (PAR) untuk analisis kuantitatif jumlah gadolinium bebas dan yang terikat dengan ligan dalam sistem. Penelitian ini adalah studi awal untuk mengamati pola kompleksasi antara Gd3+ dan molekul target yang dilakukan dalam 100 mM bufer MES pH 5.5. Konstanta pengikatan (Log K) dari kompleks Gd3+-PAR (1-1) pada pH 5.5 adalah     4.41 ± 0.09 M-1. Karena metode ini hanya menggunakan UV-Vis Spektroskopi, disimpulkan bahwa colorimetric assay yang melibatkan PAR adalah metode yang cepat dan murah untuk menganalisis aktivitas pengikatan antara Gd3+ dan ligan target. Katakunci: Gadolinium, colorimetric assay, agen pengkontras MRI. In this research, we study a colorimetric assay employing 4-(2-pyridylazo)-resorcinol (PAR) for quantifying the chelated and free gadolinium in the system. This is a preliminary study in order to observe the complexation behavior between Gd3+ and targeted molecules. This was carried out in 100 mM MES buffer at pH 5.5. The binding constant (Log K) of the Gd3+-PAR (1:1) complex at pH 5.5 is 4.41 ± 0.09 M-1. Since this method only uses UV-Vis spectrometry, it is concluded that colorimetric assay employing PAR is a fast and inexpensive method in order to analyze the binding activity between Gd3+ and targeted ligands. Keywords: Gadolinium, colorimetric assay, MRI contrast agent.","PeriodicalId":17786,"journal":{"name":"Jurnal Kimia Valensi","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46693762","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":"Sintesis dan Karakterisasi Nanopartikel Perak-Tricalcium Phosphate (TCP) dengan Bantuan Ekstrak Daun Alpukat (Percea americana)","authors":"Yessi Rahmayani, Zulhadjri Zulhadjri, Syukri Arief","doi":"10.15408/JKV.V5I1.8652","DOIUrl":"https://doi.org/10.15408/JKV.V5I1.8652","url":null,"abstract":"Sintesis nanopartikel perak-TCP telah dilakukan pada penelitian ini. Nanopartikel perak dibuat dengan mereduksi larutan perak nitrat dengan menggunakan ekstrak daun alpukat sebagai bioreduktor. Tricalsium Phosphate (TCP) dicelupkan kedalam nanopartikel perak membentuk komposit perak-tricalcium phosphate. Hasil analisis UV-Vis menunjukkan pembentukan puncak serapan nanopartikel perak pada panjang 445-446 nm, yakni puncak yang khas dari nanopartikel perak yang disebabkan oleh adanya fenomena Surface Plasmon Resonance (SPR). Penelitian ini menghasilkan perak-TCP dengan ukuran nanopartikel. Sesuai  hasil X-Ray Diffraction (XRD) yang menunjukkan bahwa ukuran kristal TCP adalah 64 nm dan ukuran Kristal perak dalam komposit adalah 46 nm. Hasil Scanning Electron Microscopy (SEM) menunjukan partikel perak terdistribusi dipermukaan partikel TCP. Kata Kunci: Komposit perak-TCP, nanopartikel perak, Percea americana,  tricalcium phosphate.  The silver-TCP nanoparticle synthesis was carried out in this study. Silver nanoparticles are made by reducing silver nitrate solution using avocado leaf extract as a bioreactor. Tricalcium Phosphate (TCP) is dipped into silver nanoparticles to form a silver-tricalcium phosphate composite. The UV-Vis analysis shows the formation of silver nanoparticle absorption peaks at a length of 445-446 nm, which is a typical peak of silver nanoparticles caused by the Surface Plasmon Resonance (SPR) phenomenon. X-Ray Diffraction (XRD) shows that the TCP crystal size is 64 nm and the size of the Silver Crystal in the composite is 46 nm. The results of Scanning Electron Microscopy (SEM) show silver particles distributed on the surface of TCP particles Keywords: Percea americana, silver-TCP composite, silver nanoparticle, tricalcium phosphate.","PeriodicalId":17786,"journal":{"name":"Jurnal Kimia Valensi","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47480465","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":"Sintesis Tetrapeptida PADY menggunakan Metode Fasa Padat dan Aktivitas Antioksidannya","authors":"Rani Maharani, Dadan Sumiarsa, Christina R. Marpaung, A. Zainuddin, Aceng Hidayat, Desi Harneti, Nurlelasari Nurlelasari, Unang Supratman","doi":"10.15408/JKV.V5I1.10500","DOIUrl":"https://doi.org/10.15408/JKV.V5I1.10500","url":null,"abstract":"Peptida antioksidan merupakan kelompok peptida yang berperan penting karena dapat menetralkan radikal bebas, sehingga dapat mencegah dan mengobati penyakit kronis. Salah satu senyawa peptida antioksidan alami yang telah ditemukan peneliti sebelumnya adalah senyawa tetrapeptida PAGY (Pro-Ala-Gly-Tyr) yang diisolasi dari gelatin kulit ikan amur sturgeon (Acipenser schrenckii) dan dilaporkan memiliki aktivitas antioksidannya dengan IC50 5.38 mg/mL dalam uji DPPH dan 0,008 mg/mL dalam uji ABTS berturut-turut. Kelompok kami telah berhasil mensintesis PAGY bersama dengan analognya yakni PSGY, PFFY, PAFY, dan PAIY dengan menggunakan metode sintesis peptida fase padat (SPPS). Pengujian aktivitas antioksidan pada senyawa hasil sintesis menunjukkan bahwa PSGY memiliki aktivitas antioksidan lebih baik dari PAGY. Pencarian analog tetrapeptida antioksidan yang lebih baik hingga saat ini masih terus dilakukan. Pada penelitian ini telah berhasil disintesis analog tetrapeptida lainnya PADY (Pro-Ala-Asp-Tyr) dengan metode sintesis peptida fase padat menggunakan strategi Fmoc/t-Bu pada resin 2-klorotritilklorida dilanjutkan dengan pengujian aktivitas antioksidannya. HATU/HOAT digunakan sebagai reagen pengkopling dalam sintesis PADY. Pemurnian krud PADY dilakukan menggunakan RP-HPLC preparatif sehingga diperoleh PADY murni seberat 14.7 mg (12.6%). Penentuan struktur peptida hasil sintesis dianalisis dengan menggunakan spektroskopi 1H-NMR dan TOF-MS. Pada pengujian aktivitas antioksidan dengan metode DPPH, PADY hasil sintesis memberikan nilai IC50 sebesar 1.850 mg/mL, yang mengindikasikan bahwa PADY menunjukkan aktivitas antioksidan yang lebih rendah daripada PAGY hasil sintesis peneliti sebelumnya. Kata kunci: Antioksidan, tetrapeptida, sintesis peptida fase padat. Antioxidant peptide is a class of peptides that play an important in neutralizing free radicals, therefore this compound can be used to prevent and treat chronic diseases. One of the natural antioxidant peptides reported by previous researcher is PAGY (Pro-Ala-Gly-Tyr), which is isolated from amur sturgeon fish (Acipenser schrenckii) gelatin that showed antioxidant activity with IC50 5.38 and 0.008 mg/mL using DPPH and ABTS assay, respectively. Our group has successfully synthesized PAGY, along with its analogues of PSGY, PFFY, PAFY, and PAIY using solid phase peptide synthesis method (SPPS). Antioxidant assay on synthesised compounds showed that PSGY has better antioxidant activity than PAGY. The search on the analogues of the antioxidant tetrapeptide was continued. From this study, a tetrapeptide analogue PADY (Pro-Ala-Asp-Tyr) has been successfully synthesised by solid phase peptide synthesis method with Fmoc/t-Bu strategy on 2-chlorotrityl chloride resin and tested for its antioxidant activity. HATU and HOAt reagents were used as the coupling reagent for the synthesis of PADY. The resulting PADY peptide solid was then purified using preparative RP-HPLC yielding PADY of 14.7 mg (12.6%). Characterisati","PeriodicalId":17786,"journal":{"name":"Jurnal Kimia Valensi","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44375001","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":"Pemanfaatan Limbah Kulit Pisang Kepok (Musa acuminate) sebagai Biosorben Ion Timbal(II)","authors":"Gatut Ari Wardani, W. Wulandari","doi":"10.15408/JKV.V4I2.6918","DOIUrl":"https://doi.org/10.15408/JKV.V4I2.6918","url":null,"abstract":"The use of waste of kepok banana’s peel to adsorb lead(II) metal ion was done. Peel of kepok banana was activated by using nitric acid before used as adsorbent. The optimum time needed by kepok banana’s peel to adsorp lrad(II) metal was 45 minutes with adsorbed metal was 41.779%. Adsorption kinetics of lead(II) at kepok banana’s peel follows kinetic model of Ho pseudo second with the value of R2 is 0.997 and k was 0.063 minutes-1. Isothermal adsorptions from lead(II) on kepok banana’s peel follows Freundlich adsorption model with R2 was 0.893 and capacity of adsorption was 54.752 mg/gram.  ","PeriodicalId":17786,"journal":{"name":"Jurnal Kimia Valensi","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-11-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42997865","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}