The Correspondence with Beer's Law for the Optical Density of Stained Protein Patterns on Filter Paper as a Function of Surface Protein Concentration

1955 ◽  
Vol 1 (5) ◽  
pp. 329-344 ◽  
Author(s):  
V H Rees ◽  
D J R Laurence
Keyword(s):  
Protein Concentration ◽  
Protein Pattern ◽  
Surface Protein ◽  
General Situation ◽  
Protein Patterns ◽  
Experimental Conditions ◽  
Scanning Method ◽  
Beer's Law ◽  
Beer’S Law ◽  
Protein Density

Abstract The results obtained here consistently failed to show deviations from Beer's law for optical densities less than 1.4, and the use of scanning as a convenient method for differential protein estimations would appear to be justified. The methods described may enable other workers to make similar tests of the method with a minimum of preliminary development, and some may succeed in obtaining significant failure of Beer's law in their apparatus. The use of apparatus of this type would enable the variation of the deviations with arrangement of the optical system, etc., to be worked out, but the following experimental conditions are already known to lead to significant deviations: 1. Use of dry paper instead of lightly oiled paper. 2. An inadequate light ifiter for the photocell. 3. An illuminated slit too long to be completely covered by the protein pattern. 4. Variations in protein density over the slit, either because the slit is too wide or because the protein pattern has been applied unevenly. 5. Use of low quality ifiter paper containing "pin holes." 6. A dye uptake which is not proportional to protein content of the paper [Martin and Franglen (14)]. The failure of Crook, Harris, and Warren (4) to substantiate Beer's law does not indicate the most general situation for the application of the scanning method. The application of Beer's logarithmic law to the scanning of dyed protein patterns has been investigated by methods described in detail. No deviations could be found for optical densities less than 1.4 for amidoschwarz 1OB or less than 1.1 for azocarmine B staining. The scanning method can be used for evaluation of protein fractions if care is taken.

scholarly journals Spectrophotometric Determination of Aciclovir, Cefepirne Hydrochloride, Etamsylate and Metoclopramide Hydrochloride Usina 1,10 Phenanttrroline—Fe(lll) Reaqent

2004 ◽  
Vol 72 (1) ◽  
pp. 73-86 ◽  
Author(s):  
Marwa S. Elazazy ◽  
Abdalla Shalaby ◽  
M. N. Elbolkiny ◽  
Hawa M. Khalil
Keyword(s):  
Spectrophotometric Determination ◽  
Pharmaceutical Formulations ◽  
Accurate Method ◽  
Pure Form ◽  
Reagent Blank ◽  
Experimental Conditions ◽  
Beer's Law ◽  
Beer’S Law ◽  
Metoclopramide Hydrochloride

A simple, rapid, sensitive and accurate method for the determination of aciclovir, cefepime HCI, etamsylate and metoclopramide HCI in pure form and in pharmaceutical formulations is developed.The method is based on the fomabon of tris(o-phenanthroline) iron(ll) complex (Ferroin) upon the reaction of the ated drugs wrth iron(lll )-o- phenanthroline mixture. The ferroin complex is colorimetncally measured at λmax 510 nm against a reagent blank. 0ptimization of the experimental conditions is described. Beer's law is obeyed in the concentration range from 0.25–30 µg ml−1 with molar absorpitivities (ε) ranging from 4.796 x 103–9.51 2 x 104 L.mol−1.cm−1 and Sandell sensitivities (S) of 2.129 x 10−3–34.5 x 10−3 µg cm−2. The developed method is applied successfully for the determination of the cited drugs in pure forms and in the corresponding pharmaceutical formulations without any interferences from common excipients.

Novel UV Spectrophotometric Method for the Quantitative Analysis of CefpodoximeProxetil in Pharmaceutical Formulations by First Derivative Technique

2017 ◽  
Vol 8 (03) ◽  
Author(s):  
Potdar S. S. ◽  
Karajgi S. R. ◽  
Simpi C. C. ◽  
Kalyane N. V.
Keyword(s):  
Quantitative Analysis ◽  
Spectrophotometric Method ◽  
Dosage Form ◽  
Pharmaceutical Formulations ◽  
First Derivative ◽  
Good Linearity ◽  
Beer's Law ◽  
Beer’S Law ◽  
Tablet Dosage ◽  
Ich Guideline

The spectrophotometric method for estimation of CefpodoximeProxetil employed first derivative amplitude UV spectrophotometric method for analysis using methanol as solvent for the drug. CefpodoximeProxetil has absorbance maxima at 235nm and obeys Beer’s law in concentration range 10-50µg/ml with good linearity i.e. r2 about 0.999. The recovery studies established accuracy of the proposed method; result validated according to ICH guideline. Results were found satisfactory and reproducible. The method was successfully for evaluation of CefpodoximeProxetil in tablet dosage form without interference of common excipients.

scholarly journals Estimation of Tadalafil Using Derivative Spectrophotometry in Bulk Material and in Pharmaceutical Formulation

2014 ◽  
Vol 2014 ◽  
pp. 1-6 ◽  
Author(s):  
Zamir G. Khan ◽  
Amod S. Patil ◽  
Atul A. Shirkhedkar
Keyword(s):  
Wavelength Range ◽  
Area Under Curve ◽  
Pharmaceutical Formulation ◽  
Second Order ◽  
Order Derivative ◽  
Uv Spectrophotometry ◽  
First Order ◽  
Beer's Law ◽  
Beer’S Law ◽  
Derivative Uv Spectrophotometry

Four simple, rapid, accurate, precise, reliable, and economical UV-spectrophotometric methods have been proposed for the determination of tadalafil in bulk and in pharmaceutical formulation. “Method A” is first order derivative UV spectrophotometry using amplitude, “method B” is first order derivative UV spectrophotometry using area under curve technique, “method C” is second order derivative UV spectrophotometry using amplitude, and “method D” is second order derivative UV spectrophotometry using area under curve technique. The developed methods have shown best results in terms of linearity, accuracy, precision, and LOD and LOQ for bulk drug and marketed formulation as well. In N,N-dimethylformamide, tadalafil showed maximum absorbance at 284 nm. For “method A” amplitude was recorded at 297 nm while for “method B” area under curve was integrated in the wavelength range of 290.60–304.40 nm. For “method C” amplitude was measured at 284 nm while for “method D” area under curve was selected in the wavelength range of 280.80–286.20 nm. For methods A and B, tadalafil obeyed Lambert-Beer’s law in the range of 05–50 μg/mL while for “methods C and D”, tadalafil obeyed Lambert-Beer’s law in the range of 20–70 μg/mL, and-for “methods A, B, C, and D” the correlation coefficients were found to be > than 0.999.

Computer Techniques for Making Beer's Law Calculations of Concentrations from Spectral Data.

1966 ◽  
Vol 38 (12) ◽  
pp. 1794-1796 ◽  
Author(s):  
D. F. Detar
Keyword(s):  
Spectral Data ◽  
Beer's Law ◽  
Beer’S Law

scholarly journals Enhancement of drought tolerance in Triticum aestivum L. seedlings using Azospirillum brasilense NO40 and Stenotrophomonas maltophilia B11

2021 ◽  
Vol 45 (1) ◽  
Author(s):  
Wedad A. Kasim ◽  
Mohamed E. H. Osman ◽  
Mohamed N. Omar ◽  
Samar Salama
Keyword(s):  
Triticum Aestivum ◽  
Drought Stress ◽  
Drought Tolerance ◽  
Azospirillum Brasilense ◽  
Stenotrophomonas Maltophilia ◽  
Protein Pattern ◽  
Triticum Aestivum L ◽  
Protein Patterns ◽  
Wheat Seedlings ◽  
Enhanced Production

Abstract Background The effectiveness of two PGPB; Azospirillum brasilense NO40 and Stenotrophomonas maltophilia B11 was investigated in enhancing the drought tolerance of wheat (Triticum aestivum L.) seedlings cultivar Gemiza9. The inoculated or uninoculated grains were sown in unsterilized sandy soil and watered normally untill the 8th day. Drought stress was initiated by completely withholding water for 7 days (until wilting). Samples were collected after 15 days from sowing to evaluate some growth criteria, damage and defense indicators and to analyze the roots’ protein pattern. Results The results showed that inoculating wheat seedlings with these strains significantly diminished the inhibitory effects of drought stress on the relative water content of roots, shoots and leaves; area of leaves; contents of pigments (chlorophyll a and b) and ascorbic acid; and on the protein patterns of roots. Moreover, the bacterial inoculation notably reduced the drought-induced damage indicated by lower leakage of electrolytes and less accumulation of Malondialdehyde and hydrogen peroxide, surprisingly with less enhanced production of proline and activities of catalase and peroxidase than their uninoculated counterparts. Under normal conditions, inoculating wheat plants with these PGPB resulted in significantly promoted growth and elevated contents of pigments and altered protein patterns of roots. Conclusion Overall, we can say that both Azospirillum brasilense NO40 and Stenotrophomonas maltophilia B11 were able to deactivate the growth inhibition in wheat seedlings to some extent, while maintaining a certain level of efficient protection against damage under drought stress.

scholarly journals A spectrophotometric method for determination of fluorophore-to-protein ratios in conjugates of the blue fluorophore 7-amino-4-methylcoumarin-3-acetic acid (AMCA)

1990 ◽  
Vol 38 (1) ◽  
pp. 87-94 ◽  
Author(s):  
M W Wessendorf ◽  
S J Tallaksen-Greene ◽  
R M Wohlhueter
Keyword(s):  
Acetic Acid ◽  
Optical Density ◽  
Extinction Coefficient ◽  
Spectrophotometric Method ◽  
Extinction Coefficients ◽  
Beer's Law ◽  
Beer’S Law ◽  
The Given

7-Amino-4-methylcoumarin-3-acetic acid (AMCA) has been found to be a useful fluorophore for immunofluorescence. The present study describes a spectrophotometric method for determining the ratio of moles AMCA to moles protein (or the f/p ratio) in an AMCA-conjugated IgG. The concentration of a substance absorbing light can be determined spectrophotometrically using Beer's Law: Absorbance = Concentration x Extinction coefficient. From Beer's law, one can derive the following formula for determining the f/p ratio of AMCA-IgG conjugates: f/p = (epsilon 280IgG).A350 - (epsilon 350IgG).A280/(epsilon 350AMCA).A280 - (epsilon 280AMCA).A350 where A is the optical density of the conjugate at the given wavelength and epsilon is the extinction coefficient of a substance at the wavelength specified. Using conjugates of model proteins, it was found that the extinction coefficients of the AMCA moiety of AMCA-conjugated protein were 1.90 x 10(4) at 350 nm and 8.29 x 10(3) at 280 nm. Similarly, it was found that the extinction coefficients of swine IgG were 1.56 x 10(3) at 350 nm and 1.26 x 10(5) at 280 nm. Thus, for AMCA-conjugated swine IgG: f/p = (1.26 x 10(5)).A350 - (1.56 x 10(3)).A280/(1.47 x 10(4)).A280 - (6.42 x 10(3)).A350 [corrected]. Based on this formula, the f/p ratios of some AMCA-IgG conjugates useful for immunohistochemistry have been found to range between 6 and 24.

Extending the Range of Beer's Law in FT-IR Spectrometry. Part I: Theoretical Study of Norton—Beer Apodization Functions

1998 ◽  
Vol 52 (11) ◽  
pp. 1403-1408 ◽  
Author(s):  
Changjiang Zhu ◽  
Peter R. Griffiths
Keyword(s):  
Theoretical Study ◽  
Ir Spectrometry ◽  
Beer's Law ◽  
Ft Ir ◽  
Beer’S Law

scholarly journals Rapid Spectrophotometric Determination of Phenoxazine

2010 ◽  
Vol 7 (2) ◽  
pp. 1001-1005
Author(s):  
Baghdad Science Journal
Keyword(s):  
Detection Limit ◽  
Spectrophotometric Determination ◽  
Acidic Medium ◽  
Absorption Maximum ◽  
Aqueous Samples ◽  
Economic Method ◽  
Beer's Law ◽  
Beer’S Law ◽  
The Stability

A rapid high sensitive and inexpensive economic method has been developed for the Determination of phenoxazine by using molecular spectrophotometry. The method is based on the oxidation of phenoxazine by potassium (meta)periodate in acidic medium. The oxidation conditions were selected to enhance the sensitivity and the stability of the pink colored species which shows an absorption maximum at 530 nm. The Beer’s law was obeyed for phenoxazine concentration range from 1 to 6 µg mL-1 with 0.003 µg mL-1 detection limit and provided variation coefficients between 0.4 to 1.7 %. This method was successfully applied for the determination of phenoxazine in aqueous samples

THE DETERMINATION OF PHOSPHOLIPID PHOSPHORUS

1949 ◽  
Vol 27e (3) ◽  
pp. 159-163 ◽  
Author(s):  
J. M. R. Beveridge ◽  
S. E. Johnson
Keyword(s):  
Color Stability ◽  
Accurate Method ◽  
Inorganic Phosphorus ◽  
Strict Adherence ◽  
Beer's Law ◽  
Beer’S Law ◽  
Excellent Color ◽  
Colorimetric Procedure

A simple accurate method for the determination of phospholipid phosphorus is described. Conditions for the digestion of phospholipid have been developed permitting the utilization of a colorimetric procedure for inorganic phosphorus that is characterized by excellent color stability and strict adherence to Beer's law over a range of 0 to 65 μgm. of phosphorus.

Beer’s Law

2013 ◽  
pp. 184-184
Keyword(s):  
Beer's Law ◽  
Beer’S Law
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