scholarly journals Extraction and Determination of Caffeine Concentrations in Coffee, Tea and Chocolate Milk Available in Saudi Markets

2019 ◽  
pp. 1-5
Author(s):  
Sarra Talab
Keyword(s):  
Saudi Arabia ◽  
Quantitative Analysis ◽  
Local Market ◽  
Chocolate Milk ◽  
Caffeine Content ◽  
Extracting Solvent ◽  
Caffeine Level

In this work a study was performed using UV/Vis spectrophotometer to determine the concentrations of caffeine in coffee, tea and chocolate milk available in local market in Riyadh, Saudi Arabia. Quantitative analysis was carried using dichloromethane as extracting solvent. Results showed that the minimum caffeine level was observed in the chocolate milk (16.38 ppm) and the highest caffeine content observes in coffee (32 ppm).

scholarly journals Trace Determination of Selected Heavy Metal Ions in Bleaching Creams in the Local Market of Saudi Arabia

2017 ◽  
Vol 14 (4) ◽  
pp. 1349-1354
Author(s):  
Faten M. Ali Zainy
Keyword(s):  
Heavy Metals ◽  
Heavy Metal ◽  
Saudi Arabia ◽  
Direct Determination ◽  
Optical Emission ◽  
Local Market ◽  
Icp Oes ◽  
Recovery Percentage ◽  
High Concentrations

ABSTRACT: Bleaching cream and cosmetics products of skin have risk of toxicity and deleterious effects to the human health because of their multiplicative contamination with heavy metals and uncertain mixing of different components. Thus, the present study reports a comprehensive study on the trace selected heavy metal (Hg, Cd, Ti, Bi, Pb, As and Tl) determination in 16 samples of bleaching creams and samples mixture of bleaching creams simultaneously to get a double activity (shiny and faster) on the skin from the local market of Saudi Arabia. Samples were digested with high pressure microwave technique followed by direct determination by inductive coupled plasma - optical emission spectrometer (ICP-OES). Hg, Bi, Ti and Pb levels on samples were found equal 5739.16, 7013.53, 21407.73, 456.70 µg/g, respectively whereas other elements (Cd, As and Tl) were found less than 28.99 ppm. One sample of the mixtures showed high concentrations of Hg (13338.50 µg/g,) and Bi (619.23 µg/g). Thus, creams and cream mixtures containing heavy metals above the permissible limit must be blind. The lower detection limits (LOD) were achieved at 2.5-50 µg/g concentration level, RSD was less than 14.72%, and recovery percentage for cosmetics were in the range of 88.52 -99.62%. The proposed method for sample digestion and ICP-OES measurements was fast, precise, convenient and provided good recovery of the tested elements.

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 Kadar Kafein Dari Serbuk Teh Hitam, Teh Hijau dan Teh Putih (Camellia sinensis L.)

2016 ◽  
Vol 1 (1) ◽  
pp. 15-17
Author(s):  
Ratih Kusuma Wardani ◽  
M. A. Hanny Ferry Fernanda
Keyword(s):  
Green Tea ◽  
Black Tea ◽  
Liquid Extraction ◽  
The Body ◽  
Uv Spectrophotometry ◽  
White Tea ◽  
Caffeine Content ◽  
Brewing Time ◽  
Caffeine Level

ABSTRAKTeh diklasifikasikan menjadi 3 jenis yaitu teh hitam, teh hijau dan teh putih. Teh mengandung senyawa kafein yang dapat bermanfaat dan merugikan bagi tubuh. Senyawa kafein dalam teh dapat dipisahkan dengan metode ekstraksi cair-cair menggunakan kloroform dan penambahan CaCO3. Penentuan kadar kafein menggunakan metode spektrofotometri UV diukur pada panjang gelombang 275 nm. Kadar kafein dipengaruhi oleh suhu dan waktu penyeduhan. Semakin tinggi suhu dan lama waktu penyeduhan, kadar kafein dalam teh semakin meningkat. Kadar kafein dari berbagai jenis teh dari kadar yang tinggi ke rendah berturut-turut yaitu serbuk teh hitam, teh putih dan teh hijau dengan suhu penyeduhan 95ᵒC selama 10 menit.Kata Kunci: Teh hitam, teh hijau, teh putih, kafein, spektrofotometri UVABSTRACTTea is classified into three type, which are black tea, green tea and white tea. Tea contains caffeine compound that can be beneficial and harmful for the body. Caffeine compound in tea can be separated by liquid extraction method using chloroform and addition of CaCO3. The determination of the caffeine content measured by UV spectrophotometry at 275 nm. Caffeine level is influenced by temperature and brewing time. The highertemperature and the longer brewing time, the level of caffeine in tea increase. The caffeine content of various types of tea from high to low level respectively are black tea powder, white tea and green tea with temperature of 95ᵒC and 10 minutes brewing time.Keywords: Black tea, green tea, white tea, caffeine, UV spectrophotometry

An Improved Quantitative Image Analyser

1977 ◽  
Vol 35 ◽  
pp. 226-227
Author(s):  
J.P. Fallon ◽  
P.J. Gregory ◽  
C.J. Taylor
Keyword(s):  
Feature Extraction ◽  
Quantitative Analysis ◽  
Frequency Content ◽  
General Sense ◽  
Physical Measurements ◽  
Quantitative Image ◽  
Image Analyser ◽  
Automatic Methods ◽  
Quantitative Results

Quantitative image analysis systems have been used for several years in research and quality control applications in various fields including metallurgy and medicine. The technique has been applied as an extension of subjective microscopy to problems requiring quantitative results and which are amenable to automatic methods of interpretation.Feature extraction. In the most general sense, a feature can be defined as a portion of the image which differs in some consistent way from the background. A feature may be characterized by the density difference between itself and the background, by an edge gradient, or by the spatial frequency content (texture) within its boundaries. The task of feature extraction includes recognition of features and encoding of the associated information for quantitative analysis.Quantitative Analysis. Quantitative analysis is the determination of one or more physical measurements of each feature. These measurements may be straightforward ones such as area, length, or perimeter, or more complex stereological measurements such as convex perimeter or Feret's diameter.

Lateral resolution of the electron microbeam analysis

1978 ◽  
Vol 36 (1) ◽  
pp. 542-543
Author(s):  
H.J. Dudek
Keyword(s):  
Quantitative Analysis ◽  
Depth Resolution ◽  
Lateral Resolution ◽  
Cylindrical Particle ◽  
Correction Procedure ◽  
X Ray ◽  
Element Concentrations ◽  
Microbeam Analysis ◽  
The Matrix

The chemical inhomogenities in modern materials such as fibers, phases and inclusions, often have diameters in the region of one micrometer. Using electron microbeam analysis for the determination of the element concentrations one has to know the smallest possible diameter of such regions for a given accuracy of the quantitative analysis.In th is paper the correction procedure for the quantitative electron microbeam analysis is extended to a spacial problem to determine the smallest possible measurements of a cylindrical particle P of high D (depth resolution) and diameter L (lateral resolution) embeded in a matrix M and which has to be analysed quantitative with the accuracy q. The mathematical accounts lead to the following form of the characteristic x-ray intens ity of the element i of a particle P embeded in the matrix M in relation to the intensity of a standard S

Application of EDS Technique for OSP Film Thickness Measurement

2006 ◽  
Author(s):  
Prong Kongsubto ◽  
Sirarat Kongwudthiti
Keyword(s):  
Thin Film ◽  
Quantitative Analysis ◽  
Joint Strength ◽  
Critical Factor ◽  
Thickness Measurement ◽  
Ic Manufacturing ◽  
And Control ◽  
Film Thickness Measurement ◽  
Non Destructive

Abstract Organic solderability preservatives (OSPs) pad is one of the pad finishing technologies where Cu pad is coated with a thin film of an organic material to protect Cu from oxidation during storage and many processes in IC manufacturing. Thickness of OSP film is a critical factor that we have to consider and control in order to achieve desirable joint strength. Until now, no non-destructive technique has been proposed to measure OSP thickness on substrate. This paper reports about the development of EDS technique for estimating OSP thickness, starting with determination of the EDS parameter followed by establishing the correlation between C/Cu ratio and OSP thickness and, finally, evaluating the accuracy of the EDS technique for OSP thickness measurement. EDS quantitative analysis was proved that it can be utilized for OSP thickness estimation.

HPLC-UV Method for Determination of Famotidine from Pharmaceutical Products

2018 ◽  
Vol 69 (2) ◽  
pp. 297-299
Author(s):  
Adriana Nita ◽  
Delia Mirela Tit ◽  
Lucian Copolovici ◽  
Carmen Elena Melinte (Frunzulica) ◽  
Dana Maria Copolovici ◽  
...  
Keyword(s):  
Acetic Acid ◽  
Quantitative Analysis ◽  
Linear Response ◽  
Mobile Phase ◽  
Acetic Acid Solution ◽  
Pharmaceutical Products ◽  
Quantification Limit ◽  
Validation Parameters ◽  
Hplc Analyses

The aim of this study was to develop and validate a rapid, accurate, and exact method for the quantitative determination of famotidine in pharmaceutical products. The HPLC analyses were performed by using a mobile phase containing methanol:1% acetic acid solution=30:7 (v/v), at a flow rate of 0.4 mL/min.The total time of the method was 10 min, and the retention time of famotidine was 4.16 min. The detection was evaluated at l=267 nm. The method has been validated by using different validation parameters. The linear response of the detector for famotidine peak area was observed at concentrations ranging from 0.1 to 0.0001 mg mL-1 , resulting in a correlation coefficient of 0.99998. The values of the detection limit and of the quantification limit are 0.00048 mg mL-1 and 0.00148 mg mL-1, respectively. The method proposed allowed accurate (with a relative error of less than 2%) and precise (RSD values less than 2.0%) determination of famotidine content in pharmaceutical products and can be used for its rapid quantitative analysis.

Examination of Conditions for the Determination of Carbamate Pesticides in Soils

1992 ◽  
Vol 57 (8) ◽  
pp. 1632-1638 ◽  
Author(s):  
Věra Tatarkovičová ◽  
Zdeněk Stránský
Keyword(s):  
Activated Carbon ◽  
Solvent Extraction ◽  
Soil Type ◽  
Extraction Procedure ◽  
Purification Procedure ◽  
Factors Affecting ◽  
Carbamate Pesticides ◽  
Rp Hplc ◽  
Extracting Solvent

The procedure for the determination of carbamate pesticides in soil was optimized. The following factors affecting the final results were investigated: extracting solvent, extraction procedure, extract purification procedure, and soil type. Triple extraction with acetone and purification of the extract on a two-stage purification column containing an activated carbon-silica gel 1+1 mixture were found optimal. The extracts after treatment were analyzed by RP-HPLC with UV detection. The method developed allows carbamate pesticides in soil to be determined at concentrations in excess of 30 μg kg-1.

Sign in / Sign up

Export Citation Format

Share Document