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"This text covers the various methods of validation for high performance liquid chromatography - mass spectrometry (LC-MS) analytical techniques and their applications in the analysis of a broad range of drugs in modern clinical pharmacology."

"Breakthroughs in combinatorial chemistry and molecular biology, as well as an overall industry trend toward accelerated development, mean the rate of sample generation now far exceeds the rate of sample analysis in the pursuit of producing new and better pharmaceuticals. LC/MS is an analytical tool that helps the researcher identify the most promising sample early in the selection process, effectively creating a shortcut to finding new drugs. This book is the first to describe LC/MS applications within the context of drug development, including the discovery, preclinical, clinical, and manufacturing phases. In addition to the thorough technical analysis of this tool, LC/MS Applications in Drug Development provides perspective on the significant changes in strategies for pharmaceutical analysis. A process overview of drug development from an analytical point of view is provided along with essential data required to successfully bring a drug to market. The incorporation of LC/MS is illustrated from target to product. Chapters pertaining to the discovery process itself include : proteomics, glycoprotein mapping, natural products dereplication, lead identification screening, open-access LC/MS, in vitro drug screening written for both the analytical chemist who uses LC/MS applications and the pharmaceutical scientist who works with the drugs they produce."

"Propolis merupakan suatu campuran resin alami yang dikumpulkan lebah dari berbagai tanaman yang dihinggapinya. Umumnya, propolis dihasilkan dalam jumlah yang banyak oleh lebah yang tidak bersengat dibandingkan lebah yang bersengat. Di Indonesia, diketahui bahwa daerah Kalimantan, terutama Kalimantan Selatan, merupakan daerah dengan variasi spesies lebah tidak bersengat tertinggi. Pada penelitian ini, dipilih tiga sampel propolis dari spesies lebah Heterotrigona itama, Geniotrigona thoracica, dan Tetragonula laeviceps asal Kalimantan Selatan. Pemilihan spesies lebah ini dilakukan berdasarkan data persebaran lebah di Indonesia yang dimiliki oleh Asosiasi Perlebahan Indonesia (API). Variasi asal daerah lebah penghasil propolis dan spesies lebah dapat menyebabkan kandungan senyawa kimia pada propolis sangat beragam. Adanya keragaman kandungan senyawa kimia pada setiap propolis akan menyebabkan senyawa bioaktif antiinflamasi yang terdeteksi juga berbeda. Oleh karena itu dilakukan identifikasi senyawa bioaktif antiinflamasi melalui pendekatan metabolomik yang mengkombinasikan metode analisis kimia dengan analisis statistik. Identifikasi senyawa metabolit secara umum dilakukan menggunakan instrumen LCMS/MS dan kemudian dipilih sembilan senyawa yang berpotensi sebagai senyawa bioaktif antiinflamasi. Identifikasi senyawa yang berperan signifikan dalam aktivitas antiinflamasi dilakukan dengan analisis statistik multivariat menggunakan data senyawa potensi bioaktif antiinflamasi dan nilai IC50 sampel propolis. Hasil penelitian ini adalah diperoleh senyawa 18-β-Glycyrrhetinic acid sebagai senyawa bioaktif antiinflamasi propolis Indonesia.

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Propolis is a natural resin mixture that bees collect from the various plants they inhabit. Generally, propolis is produced in greater quantities by stingless bees than stingless bees. In Indonesia, it is known that Kalimantan, especially South Kalimantan, is an area with the highest variety of stingless bee species. In this study, three propolis samples were selected from the bee species Heterotrigona itama, Geniotrigona thoracica, and Tetragonula laeviceps from South Kalimantan. The selection of bee species is based on data on the distribution of bees in Indonesia owned by the Indonesian Beekeeping Association (API). Variations in the origin of the propolis-producing bees and bee species can cause the content of chemical compounds in propolis to vary widely. The diversity of chemical compounds in each propolis will cause the detected anti-inflammatory bioactive compounds to be different. Therefore, identification of anti-inflammatory bioactive compounds was carried out through a metabolomics approach that combined chemical analysis methods with statistical analysis. Identification of metabolites in general was carried out using the LCMS/MS instrument and then nine compounds were selected as potential anti-inflammatory bioactive compounds. Identification of compounds that play a significant role in anti-inflammatory activity was carried out by multivariate statistical analysis using data on potential anti-inflammatory bioactive compounds and IC50 values of propolis samples. The results of this study were obtained by the compound 18-β-Glycyrrhetinic acid as an anti-inflammatory bioactive compound in Indonesian propolis."

"Pestisida dipercaya dapat menurunkan populasi hama dengan cepat sehingga meluasnya hama dapat dicegah. Residu pestisida menimbulkan efek yang dalam jangka panjang dapat menyebabkan gangguan kesehatan berupa gangguan pada sistem syaraf serta metabolisme enzim. Tujuan penelitian ini adalah untuk menentukan kadar residu pestisida yang terdapat dalam buah apel, anggur, pir dan stroberi. Sebuah metode Liquid Chromatography-tandem Mass Spectrometry (LC-MS/MS) yang cepat dan sensitif, dalam mode ionisasi elektrospray positif, telah dikembangkan untuk penentuan multi-kelas pestisida. Ekstrak diperoleh dengan menggunakan asetonitril dengan teknik preparasi sampel berbasis QuEChERS (quick, easy, cheap, effective, rugged and safe). Untuk acuan uji digunakan 3 jenis bahan aktif pestisida dari 2 golongan organofosfat dan karbamat.Dari metode validasi yang dilakukan, diperoleh nilai koefisien korelasi, R2 ≥ 0,996 dengan rentang 0-1000 ppb dan 0-1 ppm. Rentang batas deteksi (LOD) dan batas kuantisasi (LOQ) dari ketiga senyawa berkisar dari konsentrasi 0,01 ppm - 0,215 ppm. Persen perolehan kembali berkisar antara 38%-44% dengan standar deviasi relatif <16%. Persen perolehan kembali yang rendah dikarenakan komponen matriks yang terdapat dalam sampel dan juga nilai LOD yang rendah sehingga sensitivitas alat berkurang.Berdasarkan hasil analisis, pestisida dimetoat tidak terdapat dalam sampel buah anggur, stroberi, dan pir yang telah diuji. Sedangkan, residu pestisida karbaril dan klorpirifos ditemukan dalam buah-buahan tersebut dengan intensitas yang sangat rendah sehingga tidak terdeteksi oleh alat karena berada dibawah batas deteksi. Sehingga disimpulkan bahwa buah-buahan tersebut masih aman untuk dikonsumsi karena berada dibawah Batas Maksimum Residu yang ditetapkan oleh Badan Standardisasi Nasional dalam SNI 7313:2008.

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Pesticides are believed to reduce the population of pests quickly so the widespread of pests can be prevented. The effects of pesticide residues in the long term can lead to health problems such as interference with the nervous system and metabolic enzymes. The purpose of this research is to determine the pesticide residues found in apples, grapes, pears and strawberries. Samples taken at random, from traders and supermarkets in the area of Depok. A rapid and sensitive liquid chromatography-tandem mass spectrometry method, in electrospray ionization positive mode, has been developed for the determination of selected multi-class pesticides. Extracts were obtained using the acetonitrile- based QuEChERS (quick, easy, cheap, effective, rugged and safe) sample preparation technique. For the reference test used 3 types of active ingredients from two groups of pesticide which is organophosphates and carbamates.

Based on the validation methods, R2 values obtained ≥ 0,996 with a range of 0-1000 ppb and 0-1 ppm. Limit of Detection (LOD) and Limit of Quantitation (LOQ) of the third compound concentrations ranged from 0,01 ppm - 0,215 ppm. Percent recoveries ranging from 38%-44% with relative standard deviations <16%. Percent recoveries was low due to matrix components present in the sample and a low LOD?s value so that the instrument sensitivity is reduced. Data analysis samples were then interpreted, and the figures obtained were compared with standard Maximum Residue Limit pesticides listed in ISO 7313:2008.

Based on the analysis, pesticide dimethoate was not present in samples of grapes, strawberries, and pears that have been tested. However, karbaril and chlorpyrifos pesticide residues found in these fruits with a very low intensity so that was not detected by the instrument because it is below the limit of detection. Thus concluded that the fruit is still safe to eat because they are under Residue Limit set by Badan Standardisasi Nasional in SNI 7313:2008."

"Pestisida memiliki peranan penting bagi manusia khususnya dalam bidang pertanian untuk membasmi hama dan serangga agar diperoleh hasil pertanian yang baik. Namun tidak menutup kemungkinan bahwa hasil pertanian yang telah diaplikasikan pestisida tidak meninggalkan residu. Oleh karena penggunaan pestisida yang intensif di lapangan, residu pestisida dalam sayuran, terutama sayuran yang biasa dikonsumsi dalam bentuk bahan mentah, merupakan masalah yang perlu diperhatikan dalam hubungannya dengan kualitas dan keamanan sayuran terhadap kesehatan masyarakat. Untuk itu dilakukan analisis residu pestisida dalam sayuran seperti sawi, kangkung, kentang, kubis, dan tomat yang diperoleh dari pasar swalayan dan pasar tradisional. Kadar residu pestisida pada sayuran dianalisis menggunakan metode QuEChERS (Quick, Easy, Cheap, Effective, Rugged, and Safe) dan instrumen LC- MS/MS (Liquid Chromatography Tandem Mass Spectrometry). QuEChERS merupakan teknik mudah dan cepat untuk analisis pestisida dengan ekstraksi dan pemurnian. Teknik ini hanya memerlukan sedikit peralatan serta tidak meninggalkan limbah dengan jumlah yang besar sebab hanya menggunakan sedikit sampel. Berdasarkan hasil penelitian, didapatkan kandungan residu pestisida carbaryl pada sayuran kentang sebesar 3,83 ng/mL, residu pestisida carbaryl pada sayuran kubis sebesar 3,83 ng/mL, serta residu pestisida carbaryl dan chlorpyrifos pada sayuran tomat sebesar 5,46 ng/mL dan 7,40 ng/mL. Berdasarkan hasil-hasil tersebut, dapat dikatakan bahwa sayuran sawi, kangkung, kentang, kubis, dan tomat yang diperoleh dari pasar swalayan dan pasar tradisional aman dari residu pestisida sebab jumlah kadar yang diperoleh masih dibawah LoD dan batas maksimum residu yang telah ditetapkan Permentan (2011).

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Pesticides have an important role for human beings especially in the field of agriculture to eradicate pests and insects in order to obtain good crops. However, there is a chance that applying pesticides in vegetables leave many residues. Because of the intensive use of pesticides in the field, pesticide residues in vegetables, especially vegetables that commonly consumed in the form of raw materials, become an issue that needs to be considered in relation to the quality and safety of vegetables on public health. Therefore, analysis of pesticide residues in vegetables such as lettuce, kale, potatoes, cabbages, and tomatoes obtained from supermarkets and traditional markets.

Contents of pesticide residues in vegetables was analyzed using the QuEChERS (Quick, Easy, Cheap, Effective, Rugged, and Safe) and LC-MS/MS (Liquid Chromatography Tandem Mass Spectrometry) instrument. QuEChERS is an easy and fast technique for the analysis of pesticides by extraction and purification. This technique requires only minimal equipment and does not leave large amounts of waste because it only uses a small sample. Based on these results, obtained content carbaryl pesticide residues in potatoes at 3.83 ng / mL, carbaryl pesticide residues in cabbage at 3.83 ng / mL, and the pesticide carbaryl and chlorpyrifos residues in tomatoes at 5.46 ng / mL and 7.40 ng / mL. Based on these results, it can be said that the vegetables cabbage, kale, potatoes, cabbage, and tomatoes obtained from supermarkets and traditional markets safe from pesticide residue levels obtained because the number is still below the LOD and the maximum residue limits established by Permentan (2011 )."

"ABSTRAKDalam rangka mengukur kandungan vitamin B1, B2 dan B9 secara simultan dalam tepung terigu yang difortifikasi telah dikembangkan metoda yang cepat, selektif, akurat menggunakan kromatografi cair tandem triple quadrupole spektrometri massa (LC-MS/MS). Analisis dilakukan menggunakan tehnik ionisasi elektrospray (ESI) positive mode dan detektor MS-MS menggunakan multi reaction monitoring (MRM) mode. Ion prekursor dan ion produk pada m/z 265 → 144 untuk vitamin B1, 377 → 243 untuk vitamin B2, dan 442 → 295 untuk vitamin B9 digunakan untuk identifikasi dan karakterisasi.Kinerja metoda yang dievaluasi adalah selektifitas, linearitas, rentang, akurasi, limit deteksi, limit kuantitasi. Hasil analisis statistik menunjukkan selektifitas yang baik, koefisien korelasi (r2) untuk vitamin B1, B2, B9 adalah 0.9986, 0.9999, 0.9988 dengan rentang konsentrasi 0,1 ? 200 ppb, limit deteksi (LOD) 3,10 (B1), 4,60 (B2), 7,0 (B9), μg/L, limit kuantitasi (LOQ) 10,0 (B1), 15,0 (B2), 23,0 (B9), μg/L dan akurasi 90,89 % (B1), 78,11 % (B2), 64,01 % (B9).

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Abstract

In order to monitor the fortification level of vitamins B1, B2 dan B9 in wheat flours simoultansly, developed a selective, fast and accurate methods using the liquid Chromatography with tandem triple quadrupole mass spectrometry (LC-MS/MS) technique. The analysis was performed using electrospray ionization (ESI) tehnique with positive mode and the instrument was set in MRM (Multiple Reaction Monitoring) . Ion precursor and product was identified and characterized at m/z 265 → 144 for vitamin B1, 377 → 243 for vitamin B2, dan 442 → 295 for vitamin B9.

The methods performance was evaluated in regard to selectivity, linearity, range, accuracy, limit of detection, limit of quantitation. The statistical analysis of the result showed good selectivity, correlation coefficient (r2) 0.9986, 0.9999, 0.9988 vitamins B1, B2, B9 respectively, with the concentration range 0,1 ? 200 μg/L, limit of detection (LOD) 3,10 (B1), 4,60 (B2), 7,0 (B9), μg/L, limit of quantitaion (LOQ) 10,0 (B1), 15,0 (B2), 23,0 (B9), μg/L and accuracy 90,89 % (B1), 78,11 % (B2), 64,01 % (B9)."

"Sebuah metode LC-MS/MS telah dikembangkan dan divalidasi, untuk penentuan simultan dari asam trans, trans-mukonat, asam hippurat, 2-metil asam hippurat, 3-metil asam hippurat, dan 4 -metil asam hippurat dalam urin manusia sebagai biomarker dari paparan benzena, toluena dan xilena (BTX). Setelah ekstraksi fase padat dan pemisahan LC, sampel dianalisis dengan spektrometer massa triple quadrupole dan dioperasikan dalam mode ion negatif. Metode ini memenuhi kriteria validasi dalam hal linearitas, rentang, presisi, batas deteksi, batas kuantisasi, serta persen perolehan kembali. Diperoleh nilai R2 ≥ 0,996 dengan rentang 0 ppm ? 1 ppm. Nilai presisi yang dinyatakan dengan %RSD berada pada 0,784 % - 3,272 %. Batas deteksi dari lima analit berkisar antara 0,035 ppm - 0,068 ppm. Batas kuantisasi dari lima analit berkisar antara 0,117 ppm - 0,218 ppm. Persen perolehan kembali mampu mencapai kisaran 85%-99% Tingkat sensitivitas yang tinggi membuat metode ini cocok untuk pemantauan biologis rutin untuk paparan BTX baik di wilayah kerja maupun lingkungan sekitar. Metode divalidasi diterapkan untuk menilai paparan BTX dalam tubuh 7 orang petugas lalu lintas perkotaan dengan kadar BTX berkisar 0.04 ppm ? 46,21 ppm.

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A liquid chromatography?tandem mass spectrometry (LC?MS/MS) method was developed and fully validated, for the simultaneous determination of trans, transmuconic acid, hippuric acid, 2-methyl hippuric acid, 3-methyl hippuric acid, and 4-methyl hippuric acid in human urine as biomarkers of exposure to benzene, toluene and xylenes (BTX). After solid phase extraction and LC separation, samples were analyzed by a triple?quadrupole mass spectrometer operated in negative ion mode. This method of validation criteria in terms of linearity, range, precision, detection limits, quantitation limits, and percent recovery. Obtained values R2 ≥ 0.996 in the range 0 ppm - 1 ppm. Precision values are expressed as % RSD was at 0.784% - 3.272%. Detection limit of five analytes ranged from 0.02 ppm - 0.038 ppm. Quantitation limit of five analytes ranged from 0.035 ppm - 0.068 ppm. Percent recoveries are able to achieve the range of 85% -99%. Levels of high sensitivity makes this method suitable for routine biological monitoring for exposure to BTX both in the workplace or the environment. Validated method is applied to assess exposure to BTX in the body 7 of urban traffic officer with BTX levels ranging from 0:04 ppm - 46.21 ppm."