scholarly journals Analisis Kadar Kafein dalam Kopi Bubuk Lokal yang Beredar di Kota Palu

2018 ◽  
Vol 7 (4) ◽  
pp. 189
Author(s):  
I Nyoman Suwiyarsa ◽  
Siti Nuryanti ◽  
Baharuddin Hamzah
Keyword(s):  
Quantitative Analysis ◽  
Qualitative Analysis ◽  
Thin Layer ◽  
Thin Layer Chromatography ◽  
Percent Level ◽  
Caffeine Content ◽  
Coffee Powder ◽  
The City ◽  
Layer Chromatography ◽  
Caffeine Level

Analysis of caffeine level in local coffee powder that circulates in Palu city have been done. The purpose of this study was to determine the level of caffeine in local coffee powder, which is engaged in several markets in the city of Palu. Levels of caffeine in the study will be compared with the standard caffeine content according to the SNI 01-3542-2004, i.e. 0.45-2% w/w. The method used for qualitative analysis was the thin layer chromatography and for quantitative analysis was using UV-Vis spectrophotometry. The results of qualitative analysis of six local coffee powders A, B, C, D, E, and F showed each a Rf value between 0.32 to 0.40. Levels of caffeine (per 1 g of coffee powder) quantitatively ranging from brand samples A to F were 0.83, 2.06, 1.60, 2.63, 1.29, and 1.72%, respectively, percent level of caffeine of six samples of local powdered coffee, samples A, C, E and F in terms of SNI 01-3542-2004 were between 0.45-2.00% (w/w), while sample B and sample D exceeds 2% were 2.06% and 2.63%.

scholarly journals ANALISIS PEWARNA RHODAMIN B PADA SAOS BAKSO TUSUK YANG BEREDAR DIBEBERAPA SEKOLAH DASAR DI KOTA MANADO

PHARMACON ◽  
2019 ◽  
Vol 8 (1) ◽  
pp. 120
Author(s):  
Balqis Muzdhalifah ◽  
Sri Sudewi ◽  
Gayatri Citraningtyas
Keyword(s):  
Elementary Schools ◽  
Quantitative Analysis ◽  
Qualitative Analysis ◽  
Thin Layer ◽  
Thin Layer Chromatography ◽  
Food Products ◽  
Synthetic Dye ◽  
Layer Chromatography ◽  
Rhodamin B ◽  
Color Visualization

ABSTRACTRhodamin B is a red synthetic dye commonly used as paper dyes, textiles or inks. Food products that are often added by Rhodamin B by irresponsible producers is sauce. The purpose of this study was to determine the presence and levels of Rhodamin B found in skewers meatballs sold in several elementary schools in Manado City using Thin Layer Chromatography and UV-Vis Spectrophotometer. The results of the study obtained that the results of the qualitative analysis using TLC obtained 5 sampels identified based on Rf value parameters and color visualization. Quantitative analysis of UV-Vis spectrophotometer produced Rhodamin B level values for each sample which was calculated using regression formula y = 0,0726 x + 0,0432 and R2 = 0,9957. The sample code A1 was 3,443 ± 0,080 μg/mL, B1 was 3,057 ± 0,150 μg/mL, B2 was 5,881 ± 0,170 μg/mL, C1 was 3,884 ± 0,130 μg/mL, and C2 was 4,517 ± 0,140 μg/mL. The conclusion in this study is that skewer meatballs circulating in several elementary schools in Manado City contains Rhodamin B. Keywords: Rhodamin B, Skewer Meatballs Sauce, Thin Layer Chromatography, UV-Vis Spectrophotometer. ABSTRAKRhodamin B merupakan pewarna sintetik berwarna merah yang umum digunakan sebagai pewarna kertas, tekstil atau tinta. Produk pangan yang sering di tambahkan Rhodamin B oleh produsen yang tidak bertanggung jawab adalah saos. Tujuan penelitian ini adalah untuk mengetahui keberadaan dan kadar Rhodamin B yang terdapat pada saos bakso tusuk yang dijajakan pada beberapa Sekolah Dasar di Kota Manado menggunakan metode Kromatografi Lapis Tipis dan Spektrofotometer UV-Vis. Hasil penelitian yang diperoleh bahwa hasil analisis secara  kualitatif menggunakan KLT diperoleh  5 sampel teridentifikasi berdasarkan parameter nilai Rf dan visualisasi warna. Analisis kuantitatif spektrofotometer UV-Vis menghasilkan nilai kadar Rhodamin B tiap sampel masing-masing yang dihitung dengan menggunakan rumus regresi y= 0,0726 x + 0,0432 dan nilai R2 = 0,9957.  Sampel kode A1 sebesar 3,443 ± 0,080 μg/mL , B1 sebesar 3,057 ± 0,150 μg/mL, B2 sebesar 5,881 ± 0,170 μg/mL, C1 sebesar 3,884 ± 0,130 μg/mL, dan C2 sebesar 4,517 ± 0,140 μg/mL. Kesimpulan dalam penelitian ini yaitu saos bakso tusuk yang beredar di beberapa sekolah dasar di Kota Manado mengandung Rhodamin B.  Kata Kunci: Rhodamin B, Saos Bakso Tusuk, Kromatografi Lapis Tipis, Spektrofotometer UV-Vis.

Aflatoxins: Improved Resolution by Thin Layer Chromatography

1969 ◽  
Vol 52 (4) ◽  
pp. 669-672 ◽  
Author(s):  
R D Stubblefield ◽  
G M Shannon ◽  
O L Shotwell
Keyword(s):  
Quantitative Analysis ◽  
Relative Humidity ◽  
Qualitative Analysis ◽  
Thin Layer ◽  
Thin Layer Chromatography ◽  
Water Concentration ◽  
Solvent System ◽  
Solvent Systems ◽  
Layer Chromatography ◽  
System Water

Abstract Water was added to solvent systems for TLC of aflatoxins to achieve more reproducible results in laboratories where temperature and relative humidity vary. Resolution of the toxins also improved. Increments of water were added to solvent systems composed of acetone-chloroform (10 + 90, 12 + 88, and 15 + 85, v/v). As the water concentration was increased, separation of aflatoxins B2 and G1 improved. These two toxins are usually the most difficult to resolve in these solvent systems. Separations were the best with wateracetone-chloroform (1.5 + 12 + 88, v/v/v). Water added to methanol-chloroform (3 + 97, v/v) improved resolution of this solvent system but not enough for quantitative analysis, or at times, qualitative analysis. The solvent system water-methanol-ether (1 + 3 + 96, v/v/v) separated aflatoxins as well as water-acetone-chloroform (1.5 + 12 + 88, v/v/v).

Investigation and Identification of the Bromination Products of Dimethoxyamphetamines

1976 ◽  
Vol 59 (5) ◽  
pp. 1162-1169
Author(s):  
Keith Bailey ◽  
Denise R Gagné ◽  
Richard K Pike
Keyword(s):  
Magnetic Resonance ◽  
Qualitative Analysis ◽  
Thin Layer ◽  
Thin Layer Chromatography ◽  
Infrared Spectra ◽  
Proton Magnetic Resonance ◽  
Positive Identification ◽  
Aromatic Bromination ◽  
Layer Chromatography ◽  
Magnetic Resonance Spectra

Abstract The qualitative analysis of the aromatic bromination products of the 6 isomeric dimethoxyamphetamines and their hydrochloride or hydrobromide salts is described. Their ultraviolet, mass, and proton magnetic resonance spectra are not sufficiently different for distinction but infrared spectra allow a positive identification to be made and reference spectra are provided for the bromination products of 2,4-, 2,5-, 2,6-, 4,5-, and 3,5-dimethoxyamphetamines. The application of gas-liquid and thin layer chromatography for the analysis of these products is discussed. The bromination of 2,3-dimethoxyamphetamine consistently gave mixtures which could not be separated satisfactorily; spectra are included for completeness of the comparison of products.

An Improved Assay of UV-induced Thymine-Containing Dimers in Saccharomyces cerevisiae

1975 ◽  
Vol 30 (11-12) ◽  
pp. 804-810 ◽  
Author(s):  
W. W. Fäth ◽  
M. Brendel
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Quantitative Analysis ◽  
Thin Layer ◽  
Thin Layer Chromatography ◽  
Highly Efficient ◽  
Layer Chromatography ◽  
Specific Labelling

Abstract The method for assaying thymine-containing dimers in yeast is based on highly efficient ([3H]-deoxythymidine-5′-monophosphate) DNA-specific labelling and employs ascending thin layer chromatography. It allows satisfactory quantitative analysis down to UV-doses of 500 erg/mm2.

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