A COLORIMETRIC METHOD FOR MEASURING INDICAN

1960 ◽  
Vol 38 (3) ◽  
pp. 253-262 ◽  
Author(s):  
A. M. Marko ◽  
F. B. Reynolds
Keyword(s):  
Potassium Salt ◽  
Sodium Acetate ◽  
Quantitative Measurement ◽  
Colorimetric Method ◽  
Urine Samples ◽  
Review Of The Literature ◽  
Optimum Conditions ◽  
Qualitative Test ◽  
Colored Compound ◽  
Colored Reaction Product

A qualitative test for indican (indoxyl-O-sulphate, usually as the potassium salt) has been adapted for the quantitative measurement of indican. The method involves the condensation of indican and p-dimethylaminobenzaldehyde in the presence of acid to yield an orange-colored compound. When an excess of sodium acetate is added, the orange-colored reaction product is converted to a cherry-red derivative. The effects of time, acids, temperature, and concentration of reagents on the reaction have been studied and optimum conditions have been selected to obtain a standard curve.Unsatisfactory analytical results are obtained when this method is applied directly to urine samples and a method for the quantitative elution of indican from charcoal columns has, therefore, been devised. With this modification quantitative recoveries have been achieved with indican alone and with indican added to urine samples.In addition a review of the literature pertaining to indican measurement and indigoid pigments is presented.

A COLORIMETRIC METHOD FOR MEASURING INDICAN

1960 ◽  
Vol 38 (1) ◽  
pp. 253-262
Author(s):  
A. M. Marko ◽  
F. B. Reynolds
Keyword(s):  
Potassium Salt ◽  
Sodium Acetate ◽  
Quantitative Measurement ◽  
Colorimetric Method ◽  
Urine Samples ◽  
Review Of The Literature ◽  
Optimum Conditions ◽  
Qualitative Test ◽  
Colored Compound ◽  
Colored Reaction Product

A qualitative test for indican (indoxyl-O-sulphate, usually as the potassium salt) has been adapted for the quantitative measurement of indican. The method involves the condensation of indican and p-dimethylaminobenzaldehyde in the presence of acid to yield an orange-colored compound. When an excess of sodium acetate is added, the orange-colored reaction product is converted to a cherry-red derivative. The effects of time, acids, temperature, and concentration of reagents on the reaction have been studied and optimum conditions have been selected to obtain a standard curve.Unsatisfactory analytical results are obtained when this method is applied directly to urine samples and a method for the quantitative elution of indican from charcoal columns has, therefore, been devised. With this modification quantitative recoveries have been achieved with indican alone and with indican added to urine samples.In addition a review of the literature pertaining to indican measurement and indigoid pigments is presented.

scholarly journals The colorimetric and microfluidic paper-based detection of cysteine and homocysteine using 1,5-diphenylcarbazide-capped silver nanoparticles

RSC Advances ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 3295-3303 ◽  
Author(s):  
Sattar Shariati ◽  
Gholamreza Khayatian
Keyword(s):  
Silver Nanoparticles ◽  
Human Urine ◽  
Quantitative Measurement ◽  
Urine Samples ◽  
Human Urine Samples

A simple and novel portable method for the quantitative measurement of cysteine and homocysteine in human urine samples is presented.

SOME CHARACTERISTICS OF BRAIN TYROSINE HYDROXYLASE

1967 ◽  
Vol 45 (10) ◽  
pp. 1557-1563 ◽  
Author(s):  
E. G. McGeer ◽  
S. Gibson ◽  
P. L. McGeer
Keyword(s):  
Tyrosine Hydroxylase ◽  
Rat Brain ◽  
Phosphate Buffer ◽  
Sodium Acetate ◽  
Acetate Buffer ◽  
Sodium Acetate Buffer ◽  
Optimum Conditions ◽  
Hydroxylase Activity ◽  
Michaelis Constant ◽  
Brain Tyrosine Hydroxylase

Tyrosine hydroxylase from brain homogenates differed from tyrosine hydroxylase from adrenal homogenates in being particle-bound, insensitive to cofactors, possessing a lower Michaelis constant for tyrosine, and being responsive to slightly different optimum conditions of pH and buffer. The combination of 0.02 M mercaptoethanol and 0.1–1.0 mM 2-amino-4-hydroxy-6,7-dimethyltetrahydropteridine (DMPH4) increased tyrosine hydroxylase activity in beef adrenal homogenates 15-fold, but was without effect on activity in rat brain homogenates. The Km for tyrosine in beef adrenal homogenates was 4 × 10−6 M, and in rat brain homogenates was 0.45 × 10−6 M. Conversion in beef adrenal homogenates was maximum in 0.6 M sodium acetate buffer, pH 6.0, and in rat brain homogenates was maximum in 0.28 M phosphate buffer, pH 6.2.

scholarly journals The inhibition of N-acetyl-β-d-glucosaminase by the (1→4)- and (1→5)-lactones of N-acetylglucosaminic acid

1970 ◽  
Vol 119 (2) ◽  
pp. 303-306 ◽  
Author(s):  
T. E. Couling ◽  
R. Goodey
Keyword(s):  
Paper Chromatography ◽  
Relative Stability ◽  
Quantitative Measurement ◽  
Colorimetric Method ◽  
Countercurrent Distribution

The inhibition of N-acetyl-β-d-glucosaminase activity by 2-acetamido-2-deoxy-d-gluconolactone was examined. Separation of the (1→4)- and (1→5)-lactones was achieved by using paper chromatography or countercurrent distribution and identification was obtained by examination of the relative stability of the components of separated material. Quantitative measurement of the two lactones was by kinetic titration or by a colorimetric method based on their reaction with hydroxylamine. It was shown that only the (1→5)-lactone acted as an inhibitor of N-acetyl-β-d-glucosaminase.

scholarly journals PEMBUATAN SELULOSA ASETAT DARI α -SELULOSA TANDAN KOSONG KELAPA SAWIT

2013 ◽  
Vol 2 (3) ◽  
pp. 33-39 ◽  
Author(s):  
M Roganda L Lumban Gaol ◽  
Roganda Sitorus ◽  
Yanthi S ◽  
Indra Surya ◽  
Renita Manurung
Keyword(s):  
Acetic Acid ◽  
Oil Palm ◽  
Sodium Acetate ◽  
Glacial Acetic Acid ◽  
Acid Anhydride ◽  
Ftir Analysis ◽  
Optimum Conditions ◽  
Empty Fruit Bunches ◽  
Last Stage ◽  
Cellulose Materials

Utilization of empty fruit bunches of oil palm in Indonesia is still very low, so it should be developed further. One of them by researching the manufacture of cellulose acetate from oil palm empty fruit bunches. The process used in this study is the cellanase with α-cellulose materials. Stages reaction is activation, acetylation, hydrolysis, neutralization and drying. Activation in thethree-neck flask with the addition of 50 ml of glacial acetic acid and stirredfor 3 hour,then added 15 ml of acetic acid anhydride as acetylation agent. Acetylation performed with the variation of time, 2, 2.5, 3, 3.5 hours.  In the hydrolysis step, add 2 ml of water and5 ml of glacial acetic acid. The reaction lasted for 30 minutes, then added 1 g of sodium acetate for neutralization, neutralization lasts for 5 minutes.  Then do the washing up to the smell of acetic acid is lost, and the last stage is the drying is done with a temperature below 50 oC.  The resulting products are then analyzed the degree of substitution, melting point, and then carried out FTIR analysis.  The results obtained when the optimum conditions for the acetylation reaction is 2.5 - 3 hours.

scholarly journals Au Extraction from Mineral Rocks with Aeration-Cyanidation Hydrometallurgy and Comparative Study of Its Effectiveness in Various Methods and Solvents

2019 ◽  
Vol 4 (2) ◽  
pp. 115
Author(s):  
Dhita Ariyanti ◽  
Muhammad Syaifuddin
Keyword(s):  
Economic Value ◽  
Liquid Extraction ◽  
Optimum Conditions ◽  
Sodium Bisulphite ◽  
Membrane Method ◽  
Qualitative Test ◽  
Hydrometallurgical Method ◽  
Characterization Test ◽  
Gold Metal ◽  
Better Than

<p>Indonesia is a country with abundant mining potential, one of it is gold (Au) which has a high economic value. Separation of gold metal from mineral rock consists of several methods, such as extraction, hydrometallurgy, and membrane emulsifier technology. These three methods produce different effectiveness of percentage recovery (%recovery), depend on the optimum conditions of each method and type of solvent. This study aims to separate the gold metal from mineral rocks through the hydrometallurgical method with an aeration-cyanidation solvent combination. Hidrometallurgy method is liquid extraction from ores. The test used is a qualitative test of SnCl<sub>2</sub> solution and characterization test with XRF. The results showed that the percentage of recovery (%recovery) of Au with aeration and cyanidation process for 24 hours was 92.8%. Aeration and cyanidation better than emulsifier membrane method and hydrometallurgy with sodium bisulphite, hydrogen peroxide, Cyanex 272 and NH<sub>4</sub>Cl 0.9 M.</p>

scholarly journals The role of neuroplasticity in stroke nursing

2021 ◽  
Vol 17 (2) ◽  
pp. S20-S25
Author(s):  
Niamh C Kennedy
Keyword(s):  
Brain Damage ◽  
Multidisciplinary Team ◽  
Recovery Process ◽  
Stroke Recovery ◽  
Pivotal Role ◽  
Review Of The Literature ◽  
Optimum Conditions ◽  
Stroke Patients ◽  
Role Of Nursing

Background: Neuroplasticity refers to the brain's ability to reorganise and change in response to experience or after brain damage. Neuroplasticity is an imperative component of recovery from stroke, and rehabilitation aims to capitalise on this during a patient's recovery. Aims: To highlight the role of neuroplasticity in stroke recovery and to explore how stroke nursing can use it. Methods: The paper is a narrative review of the literature on neuroplasticity and role of nursing in stroke recovery. Findings: Nurses can play a pivotal role in ensuring optimum conditions for neuroplasticity through a variety of means. These include the encouragement of repetition, integration of repetition into everyday tasks, creating a stimulating environment, educating stroke patients as well as their carers about the recovery process and working as part of multidisciplinary team. Conclusions: This paper highlights the important role stroke nursing can play in enhancing neuroplasticity during stroke recovery.

scholarly journals Penetapan Kadar Flavonoid Total Ekstrak Etanol Biji Pinang (Areca catechu L.) Menggunakan Metode AlCl3

2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Agitya Resti Erwiyani ◽  
Dina Sihot Rejeki Gultom ◽  
Dian Oktianti
Keyword(s):  
Ethyl Acetate ◽  
Colorimetric Method ◽  
Betel Nut ◽  
Standard Curve ◽  
Areca Catechu ◽  
Qualitative Test ◽  
Quercetin Concentration ◽  
The Relationship ◽  
Curve Equation

Pinang merupakan tanaman yang banyak tersedia di Indonesia dan memiliki berbagai manfaat. Pemanfaatan air rebusan biji pinang digunakan masyarakat dalam membersihkan dan menyembuhkan luka infeksi. Biji pinang mengandung senyawa fenolik seperti flavonoid, tannin, asam galat, katekin, beta-sitosterol, gum dan asam amino. Biji pinang dilakukan purifikasi untuk mengilangkan zat ballast yang tidak dibutuhkan. Penelitian ini bertujuan untuk menetapkan kadar flavonoid total ekstrak kasar dan ekstrak terpurifikasi. Metode yang digunakan dalam penetapan kadar adalah metode kolorimetri AlCl3. Penetapan kadar flavonoid dilakukan pada panjang gelombang 413,5 nm dengan standar baku pembanding kuersetin. Plot hubungan antara konsentrasi kuersetin versus absorbansi diperoleh persamaan kurva baku sebesar y = 0,0088x – 0,17 dengan nilai R2 sebesar 0,9998. Uji kualitatif menunjukkan ekstrak biji pinang tanpa purifikasi, dengan perlakuan purifikasi n-heksan dan etil asetat mengandung metabolit sekunder diantaranya flavonoid, saponin, tannin dan fenol. Purifikasi pelarut n-heksan didapatkan hasil rendemen lebih banyak dibandingkan ekstrak yang dipurifikasi dengan pelarut etil asetat. Kadar flavonoid ekstrak tanpa purifikasi, ekstrak purifikasi pelarut n-heksan dan etil asetat berturut – turut sebesar 69,13 ; 130,3 ; dan 94,73 mgQE/g. Hal tersebut sebanding dengan perolehan % rendemen tertinggi diperoleh dari ekstrak terpurifikasi n-heksan. Purifikasi pada ekstrak akan menyebabkan hilangnya zat ballast dalam ekstrak sehingga kandungan flavonoid pada ekstrak akan lebih tinggi.Kata kunci : flavonoid, metode AlCl3, ekstrak, purifikasiAreca nut is a plant that is widely available in Indonesia and has various benefits. Utilization of boiled betel nut water is used by the community to clean and heal infected wounds. Betel nuts contain phenolic compounds such as flavonoids, tannins, gallic acid, catechins, beta-sitosterol, gum, and amino acids. Areca seeds are purified to remove unnecessary ballast substances. This study aims to determine the total flavonoid levels of crude extract and purified extract. The method used in the assay is the AlCl3 colorimetric method. Determination of flavonoid levels was carried out at a wavelength of 413.5 nm with a quercetin standard. The plot of the relationship between quercetin concentration versus absorbance obtained a standard curve equation of y = 0.0088x - 0.17 with an R2 value of 0.9998. The qualitative test showed that betel nut extract without purification, with purification treatment of n-hexane and ethyl acetate, contained secondary metabolites including flavonoids, saponins, tannins, and phenols. The purification of the n-hexane solvent obtained more yields than the extract purified with ethyl acetate solvent. The flavonoid levels of the extract without purification, the purified extract of n-hexane and ethyl acetate were 69.13; 130.3; and 94.73 mg QE / g. This is comparable to the highest% yield obtained from purified extracts of n-hexane. Purification of the extract will cause the loss of ballast substances in the extract so that the flavonoid content in the extract will be higher.Keywords: flavonoids, AlCl3 method, extract, purification

Colorimetric Method for the Determination of Starch in Tobacco

1972 ◽  
Vol 55 (1) ◽  
pp. 209-213
Author(s):  
A J Sensabaugh ◽  
Kenneth L Rush
Keyword(s):  
Acid Treatment ◽  
Quantitative Measurement ◽  
Starch Content ◽  
Colorimetric Method ◽  
Colored Complex ◽  
Iodine Complex ◽  
Mesh Screen ◽  
Colorimetric Data ◽  
Tobacco Sample

Abstract A method is presented for extracting and determining the starch content of tobacco. Dried tobacco is ground to pass a 60 mesh screen, interfering colored materials are removed from the tobacco by a methanol-water extraction, and the starch is extracted from the tobacco by a perchloric acid treatment. Final quantitative measurement of the starch is made on a colored starch–iodine complex. The absorbance of this colored complex at 600 nm is proportional to the concentration of the starch in solution and can be related to the starch content of the original tobacco sample. Also included is a procedure for the isolation of pure tobacco starch. Such material was prepared for use as a calibration standard needed for the calculation of starch content of tobacco samples from the colorimetric data.

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