They are used to visually signal the acidity or alkalinity of an aqueous (water-based) solution. Despite its larger molecular weight of 670g/mol it runs faster than Xylene cyanol (539g/mol) because of its larger negative charge (hydroxyl groups).. Bromophenol blue is also a pH indicator which is yellow below pH=3 . Demonstration experiments using universal indicators. Since acetic acid is a weak acid and sodium hydroxide is a strong base, that is, base is stronger than acid: pH(end point) = pH(equivalence) A typical recipe includes 1-propanol, sodium salt, sodium hydroxide, monosodium salt, phenolphthalein, methyl red, bromothymol blue, and thymol blue. Since the relative strength of the acid and base determined by working backwards agrees with the information given in the question we are reasonably confident that our answer is plausible. Call 800-372-6726. Bromophenol Blue sodium salt (3,3,5,5-Tetrabromophenolsulfophthalein); Undefined, for electrophoresis; Suitable for use with agarose or polyacrylamide gel electrophoresis (PAGE); Bromophenol blue sodium salt is used as tracking dye in electrophoresis; Bromophenol Blue is a pH indicator, and a range for several different indicators. Reference: C.A. This 30 mL (one ounce) bottle of bromophenol blue (also known as bromphenol blue) is a 0.4% solution in water. Your email address will not be published . However, the apparent color shifts mostly depend on the concentration and/or path length through which the solution is observed. Advantec MFS 7010030 pH Test Paper, Narrow Range, Booklet, Bromophenol Blue, pH 2.8-4.4, 7mm Width, 70mm Length (Pack of 200) [7][8] A common demonstration of BTB's pH indicator properties involves exhaling through a tube into a neutral solution of BTB. (2) What is the relationship between what you know and what you need to find out? Bromophenol blue (BPB) is most commonly used as an agarose gel electrophoresis size marker. As a biological stain, it plays an important role to stain proteins and nucleic acids. The solution was poured (20 mL) into Petri dishes and 1 mM ampicillin was added to . to light purple to dark purple. Compare this item Bromophenol Blue sodium salt BeanTown Chemical Please do not block ads on this website. We can rule out bromophenol blue [5], Bromothymol blue is synthesized by addition of elemental bromine to thymol blue in a solution in glacial acetic acid. The test may be false-positive in the presence of other alkaline substances such as blood or semen, or in the presence of bacterial vaginosis. As an acidbase indicator, its useful range lies between pH3.0 and 4.6. Copyright 2006-2023 Thermo Fisher Scientific Inc. All rights reserved, Spectroscopy, Elemental and Isotope Analysis. Preparation of 6X DNA Loading Dye (Bromophenol blue, Xylene Cyanol FF, Ficoll 400) - Laboratory Notes. strong acid + weak base, resultant solution pH < 7 (acidic), weak acid + strong base, resultant solution pH > 7 (basic), strength of acid = strength of base, resultant solution pH = 7 (neutral). indicator that undergoes a color change over this range. Some content on this page could not be displayed. Bromophenol blue is used as a tracking dye in electrophoresis, as a color marker in gel electrophoresis and polyacrylamide gel electrophoresis. Store at 4C. Beyond the ranges shown, the color of the indicator will remain the same. pH's yielding the characteristic sigmoid shaped titration curve. Bromophenol blue is used as a tracking dye for electrophoresis. (c) You may be expected to calculate the pH of the solution. They are used to visually signal the acidity or alkalinity of an aqueous (water-based) solution. It is a good indicator of dissolved carbon dioxide (CO2) and other weakly acidic solutions. In PH. pH indicators generally change color over a range of two pH units. This phenomenon is called dicromatic colour[1].. Bromophenol blue is commonly used in entry-level lab courses to stain proteins in wet-mount slides. Please enable javascript and pop-ups to view all page content. need to select the indicator that would best show that the pH of a solution has Bromophenol Blue. arrow_forward. Bromophenol is also used as a colour marker to monitor the process of agarose gel electrophoresis and polyacrylamide gel electrophoresis. This Thermo Scientific Chemicals brand product was originally part of the Alfa Aesar product portfolio. [3] Highly acidic Bromothymol blue is magenta in color. Work backwards: Assume we use phenolpthalein, what sort of acid and base would be used in the titration? Different indicators change color . Search It is typically sold in solid form as the sodium salt of the acid indicator. The solution's pH will range from 2.8 to 4.5. (see Calculating pH of Aqueous Salt Solutions). . would be best to show that the pH of a solution has changed from eight to 11 is The background colour represents the colour of the solution containing the indicator over the same range of pH values. Which indicator is blue at a pH of Since the equivalence point for the titration (pH=7) occurs within the pH range for the visible colour change of the indicator (the end point between pH 6.8 and 8.4), this indicator can be used for this titration. pH No information available Melting Point/Range 279 C / 534.2 F Boiling Point/Range No information available Flash Point No information available Evaporation Rate Not applicable Flammability . below a pH of three and blue above a pH of approximately 4.6. Solutions of the dye therefore are blue. bromophenol blue, that is often used as an acid-base indicator. Using bromothymol blue you wouldn't be able to distinquish between an acid with pH 4 from an acid with pH 5. At the equivalence point the only species in solution is NaCl(aq) which has pH=7. At low pH, the dye absorbs ultraviolet and blue light most strongly and appears yellow in solution. over different pH ranges. and bromothymol blue, as from pH eight to 11 both indicators will remain blue. (ii) Decide on the pH range of the indicator and hence name the most suitable acid-base indicator to use: Ideally, indicator's colour change at the end point should occur at the same pH as the equivalence point of the neutralisation reaction. Thermo Fisher Scientific. Nagwa uses cookies to ensure you get the best experience on our website. Determine the pH of the solution at the equivalence point: Use a table of indicator colour and pH range to choose an indicator which changes colour over a pH range that includes the equivalence point. Bromophenol blue is used as a tracking dye in electrophoresis, as a color marker in gel electrophoresis and polyacrylamide gel electrophoresis. On these ranges, phenolphthalein goes from colorless to pink, methyl red goes from red to yellow, and bromothymol blue goes from yellow to blue. Customers are responsible for shipping costs. pH of five is bromophenol blue. Notes In solution at pH 3.6 (in the middle of the transition range of this pH indicator) obtained by dissolution in water without any pH adjustment, bromophenol blue has a characteristic green red color. Some documentation and label information may refer to the legacy brand. Part 2. (Its peak absorbance is 600nm at a basic pH of 12.) . [2], The presence of one moderate electron-withdrawing group (bromine atom) and two moderate donating groups (alkyl substituents) are responsible for bromothymol blue's active indication range from a pH of 6.0 to 7.6. (i) Decide the pH at the equivalence point of the titration: For an acid-base titration, the pH of the final solution depends on the relative strength of the acid and the strength of the base: acid stronger than base: pH(equivalence) < 7, strength of acid = strength of base: pH(equivalence) = 7, base stronger than acid: pH(equivalence) > 7. Search pH < 6.0 the solution appears to be yellow, at the end point, between pH 6.2 and 7.6, the solution appears to be green (an equimolar mixture of blue and yellow), pH < 6.8 the solution appears to be yellow, at the end point, between pH 6.8 and 8.4, the solution appears to be orange (an equimolar mixture of red and yellow), pH < 8.0 the solution appears to be yellow, pH > 9.6 the solution appears to be blue, at the end point, between pH 8.0 and 9.6, the solution appears to be green (an equimolar mixture of yellow and blue), pH < 8.3 the solution appears to be colourless, pH > 10.0 the solution appears to be magenta, at the end point, between pH 8.3 and 10.0, the solution appears to be pale pink (an equimolar mixture of colourless and magenta), pH > 6.0 the solution appears to be yellow, at the end point, between pH 4.4 and 6.0, the solution appears to be orange (an equimolar mixture of pink and yellow). It is sometimes used to define cell walls or nuclei under the microscope. BUT phenolphthalein changes colour between pH 8.3 and 10.0, so, at the equivalence point the phenolphthalein remains colourless. At neutral pH, the dye absorbs red light most strongly and transmits blue light. pH range > 7 therefore the base must be stronger than the acid. Xylene cyanol and orange G may also be used for this purpose.[6]. Save my name, email, and website in this browser for the next time I comment. Foster, L. S.; Gruntfest, I. J. Bromophenol blue (115-39-9) Chemical Names and Synonyms. Consider thymol blue (pH range 8.0 - 9.6) or phenolphthalein (8.3 - 10.0) as suitable indicators. Expert Solution. When the pH increases to about 3.1, the colour of the indicator starts to look more orange than red so the end point of the titration as indicated by the indicator has been reached. Your email address will not be published. The table below shows the color range for several different indicators. Imagine we are adding NaOH(aq) to HCl(aq) in a conical flask. Contribute to chinapedia/wikipedia.en development by creating an account on GitHub. An appropriate indicator for an acid-base titration will change colour over a narrow pH range, and have distinctive colour at lower pH and a different, distinctive colour at higher pH. For a given solute, there is often one wavelength (or a small range of wavelengths) at which the absorbance is greatest (and therefore the transmittance the least). each of the three remaining indicators. Some examples are given below: Methyl red : published 3.1 to 4.4 (total interval 1.3 pH units) bromophenol blue: published 3.0 to 4.6 (total interval 1.6 pH units) The original Alfa Aesar product / item code or SKU reference has not changed as a part of the brand transition to Thermo Scientific Chemicals. Let us know if you liked the post. It is employed as an electrophoresis tracking dye and also finds its uses as an industrial dye, a laboratory acid-base indicator and a biological stain to detect proteins and nucleic acids (absorbance at 610 nm), particularly when staining living tissues. As we slowly add NaOH (base) to the acid, the pH gradually increases. The indicator that would be best to show that the pH of a solution has changed from 8 to 11 will be an indicator that undergoes a color change in this pH range. Ground-only (No-Fly) chemicals are limited to the 48 contiguous U.S. states and Canada. No ads = no money for us = no free stuff for you! Since the equivalence point for the titration (pH=5.28) occurs within the pH range for the visible colour change of the indicator (the end point between pH 4.4 and 6.0), this indicator can be used for this titration. show that the pH of a solution has changed from eight to 11? The nature of this aqueous salt solution determines the pH of the resultant solution. As a pH indicator, bromothymol blue, for example, would be useful between from about pH 6.0 to pH 7.6. Bromthymol blue changes color over a pH range from 6.0 (yellow) to 7.6 (blue). Most living tissues prosper at a near-neutral pHthat is, a pH close to 7. Bromothymol blue has been used in conjunction with phenol red to monitor the fungal asparaginase enzyme activity with phenol red turning pink and bromothymol blue turning blue indicating an increase in pH and therefore enzyme activity. The litmus test is quick and simple, but it suffers from a few limitations. Therefore: pH(end point) > 7, Phenolphthalein would be the best choice because its whole pH range is greater than 7, that is, its pH range is 8.3 - 10.0. 1 equivalent of a base is the quantity which supplies 1 mole of OH-. Uses of bromophenol blue indicator include testing for soap in unwashed biodiesel and glycerol. BUT the equivalence point of the titration will not occur until well after this colour change, at pH=7, so the end point occurs BEFORE the equivalence point. Which indicator is blue at a pH of 5? J Adv Res.2016 Jan;7(1):113-24. Bromophenol blue changes color at pH less than 7 Antacid titration is an acid-base titration in which antacid that acts as bases and is mainly composed of metal hydroxides like NaOH reacts with excess amount of acid such as HCl. To answer the first question, we T21481 CAS 115-39-9. Xylene cyanol and Orange G may also be used for this purpose. An intermediate of the deprotonation mechanism is responsible for the greenish color in neutral solution.[2]. It is mostly used in applications that require measuring substances that would have a relatively neutral pH (near 7). When cells are grown in tissue culture, the medium in which they grow is held close to this physiological pH. 3,3-Bis[3-bromo-4-hydroxy-2-methyl-5-(propan-2-yl)phenyl]-2,1, InChI=1S/C27H28Br2O5S/c1-13(2)17-11-20(15(5)23(28)25(17)30)27(19-9-7-8-10-22(19)35(32,33)34-27)21-12-18(14(3)4)26(31)24(29)16(21)6/h7-14,30-31H,1-6H3, InChI=1/C27H28Br2O5S/c1-13(2)17-11-20(15(5)23(28)25(17)30)27(19-9-7-8-10-22(19)35(32,33)34-27)21-12-18(14(3)4)26(31)24(29)16(21)6/h7-14,30-31H,1-6H3, Brc1c(O)c(cc(c1C)C3(OS(=O)(=O)c2ccccc23)c4cc(c(O)c(Br)c4C)C(C)C)C(C)C, Except where otherwise noted, data are given for materials in their, http://www.sciencelab.com/msds.php?msdsId=9927468, "Substituent effects on absorption spectra of pH indicators: An experimental and computational study of sulfonphthaleine dyes", "Thin film optical BTB pH sensors using solgel method in presence of surfactants", "The Equilibrium Constant for Bromothymol Blue: A General Chemistry Laboratory Experiment Using Spectroscopy", "Isolation and screening of L-asparaginase free of glutaminase and urease from fungal sp", "The determination of rupture of the membranes", Bromothymol Blue (Sodium Salt) -Sigma Aldrich, https://en.wikipedia.org/w/index.php?title=Bromothymol_blue&oldid=1138089652, Short description is different from Wikidata, Pages using collapsible list with both background and text-align in titlestyle, Articles containing unverified chemical infoboxes, Creative Commons Attribution-ShareAlike License 3.0, This page was last edited on 7 February 2023, at 23:58. Beyond the ranges shown, the color Ideally: pH at the end point = pH at the equivalence point. In solution at pH3.6 (in the middle of the transition range of this pH indicator) obtained by dissolution in water without any pH adjustment, bromophenol blue has a characteristic green red colour, where the apparent colour shifts depending on the concentration and/or path length through which the solution is observed. Our ammo is only required to be shot with our rental guns. that undergo a color change over a specific pH range. Required fields are marked *. Copyright 2023 The gel must firstly be immersed in a fixation solution containing acid (phosphoric acid or acetic acid) and alcohol (ethanol or methanol) as a . An aqueous solution of acetic acid (ethanoic acid), CH3COOH(aq), is a weak acid. Bromthymol blue changes color over a pH range from 6.0 (yellow) to 7.6 (blue). A suitable indicator would be methyl red (pH range 4.4 - 6.0), The equivalence point for the reaction is represented by the blue line at pH=5.28. [8] This means it has the largest change in colour hue, when the thickness or concentration of observed sample increases or decreases. Jul 2018 - Present4 years 9 months. Bromophenol Blue is the standard that is almost always used on a polyacrylamide gel cast in a solution of dodecyl sulfate. Bromothymol is used in obstetrics for detecting premature rupture of membranes. Magic Pitcher Demonstration. cresolphthalein. They would both appear yellow. 3,3-bis(3,5-dibromo-4-hydroxyphenyl)-3H-2,1-benzoxathiole-1,1-dione, OC1=C(Br)C=C(C=C1Br)C1(OS(=O)(=O)C2=CC=CC=C12)C1=CC(Br)=C(O)C(Br)=C1, Visual transition interval pH 3.0 (yellow) to pH 4.6 (blue). METHYL RED: The IUPAC name for methyl red is 2 -(N, N-dimethyl-4-aminophenyl) azobenzene carboxylic acid. Bromothymol blue is the most commonly used pH indicator and is in low concentration and size container and low toxicity. Indicator Thymol Blue Bromophenol Blue pKa 1.65 4.10 5.00 Methyl Red Bromothymol Blue Phenophthalein The K values for citric acid are: 7.30 9.50 4 Ka1 = 8.4 x 10-4 Ka2 = 1.8 x 10-5 Ka3 = 4.0 x 10-6. Reaxys. Bromophenol blue has a characteristic green red color in solution at pH 3.6 (in the middle of the transition range of this pH indicator). want to know which indicator is blue at a pH of five. changed from eight to 11. alizarine yellow is yellow, cresolphthalein is colorless, bromothymol blue is The table shows us the range of pH values in which four different indicators change color. Catalog No. yellow, and bromophenol blue is blue. Despite its name, bromothymol blue solution may sometimes appear . A small amount of phenol red added to this growth medium will have a pink-red color under normal conditions. Learn more about our Privacy Policy. This indicator turns red when it is added to acidic solutions. Here, weve extended the colors for Description. Find out how LUMITOS supports you with online marketing. So bromophenol blue will be yellow Other indicators work in different pH ranges. Not for Human or Veterinary or Therapeutic Use. This Thermo Scientific Chemicals brand product was originally part of the Alfa Aesar product portfolio. A suitable indicator for the titration of the weak acid CH3COOH(aq) and the strong base NaOH(aq) would be either thymol blue (pH range 8.0 - 9.6) or phenolphthalein (pH range 8.3 - 10.0). 3,3,5,5-tetrabromophenolsulfonephthalein, BPB, Albutest, Tetrabromphenol Blue, Oc1c(Br)cc(cc1Br)C2(OS(=O)(=O)c3ccccc23)c4cc(Br)c(O)c(Br)c4, 1S/C19H10Br4O5S/c20-12-5-9(6-13(21)17(12)24)19(10-7-14(22)18(25)15(23)8-10)11-3-1-2-4-16(11)29(26,27)28-19/h1-8,24-25H. All rights reserved. five? An aqueous solution of sodium hydroxide, NaOH(aq), is a strong base. 1997-2023 LUMITOS AG, All rights reserved, https://www.chemeurope.com/en/encyclopedia/Bromophenol_blue.html, Your browser is not current. So the indicator that is blue at a An aqueous solution of hydrochloric acid, HCl(aq), is a strong acid. To prepare a solution for use as indicator in volumetric work, dissolve 0.1g in 100cm3 of 50% (v/v) ethanol.[5]. This phenomenon is called dichromatic color. What would happen if we used phenolphthalein? Animal Cell Culture. The table below gives a list of common laboratory pH indicators. This means that we should select an Hearing and eye protection rentals are available for $0.50 each. Used as a pH indicator, it changes color over a pH range from 3.0 (yellow) to 4.6 (blue). When the bromophenol blue migration front reaches the bottom of the gel, the second dimension is finished and the acrylamide gel can be removed from the glass plates. Chris should use the phenolphthalein indicator. Choose an indicator that changes colour at pH=7, Choose an indicator that changes colour at pH < 7, Choose an indicator that changes colour at pH > 7. [9] However, a recent study suggests that methyl red is more useful in determining activity due to the bright yellow ring formed in the zone of enzyme activity.[10]. $12.00 for second shooter on same lane. Since bromophenol blue carries a slight negative charge at moderate pH, it will migrate in the same direction as DNA or protein in a gel; the rate at which it migrates varies according to gel density and buffer composition, but in a typical 1% agarose gel in TAE buffer or TBE buffer, bromophenol blue migrates at the same rate as a DNA fragment of approximately 500 base pairs. [5] Bromophenol blue is structurally related to phenolphthalein (a popular indicator). It may also be used in the laboratory as a biological slide stain. Titrate to pH 6.8 with conc. Bromophenol blue is also used as a color marker to monitor the process of agarose gel electrophoresis and polyacrylamide gel electrophoresis. In practice, pH(equivalence) occurs within the pH range of the indicator: pH(lower limit colour change) < pH(equivalence point) < pH(upper limit colour change)(. Read what you need to know about our industry portal chemeurope.com. . The background colour represents the colour of the solution containing the methyl red indicator over the same range of pH values. All products from TargetMol are for Research Use Only. At low pH, the dye absorbs ultraviolet and blue light most strongly and appears yellow in solution. On this Wikipedia the language links are at the top of the page across from the article title. More soluble in methyl and ethyl alcohols ,benzene, and in acetic acid. a drastic color change from approximately pH eight to pH 10, changing from colorless Clinical trial: N/A. Bromophenol blue, Tetrabromophenolsulfonephthalein, is an acid-base indicator whose useful range as an indicator lies between pH 3.0 and 4.6. M r range % acrylamide Deionized . Preparation of 6X DNA Loading Dye (Bromophenol blue, Xylene Cyanol FF, Ficoll 400) - Laboratory Notes, Ammonium Acetate [CH3COONH4] Molecular Weight Calculation, Aluminum Sulfide [Al2S3] Molecular Weight Calculation, Aluminum Oxide [Al2O3] Molecular Weight Calculation, Aluminum Fluoride [AlF3] Molecular Weight Calculation, Aluminum Bromide [AlBr3] Molecular Weight Calculation, Aluminum Sulfate [Al2(SO4)3] Molecular Weight Calculation, Aluminum Hydroxide [Al(OH)3] Molecular Weight Calculation. Because acetic acid is a weak acid, Chris has decided to titrate it with an aqueous solution of sodium hydroxide because this is a strong base. Question: Chris the Chemist has been asked to determine the concentration of acetic acid (ethanoic acid) in Gran's homemade apple cider vinegar. The original Alfa Aesar product / item code or SKU reference has not changed as a part of the brand transition to Thermo Scientific Chemicals. In vivo: So far, bromophenol blue has not been employd in animal in vivo study. Initially there is a large excess of acid, the solution is acidic, and the phenolphthalein indicator is colourless. Range Time (Non-Members) $20.00 per visit. The general carbon skeleton of bromothymol blue is common to many indicators including chlorophenol red, thymol blue, and bromocresol green. During this experiment, the yeast acted as a catalyst to remove oxygen from the hydrogen peroxide. The bromophenol blue is also used as a dye. To use all the functions on Chemie.DE please activate JavaScript. Weak acid + strong base salt + water Bromophenol blue is also used as a pH indicator with a transition range of pH 3 to 4.6. What would happen if we used a different indicator instead? It is a good indicator of dissolved carbon dioxide (CO 2) and other weakly acidic solutions. [11] Amniotic fluid typically has a pH > 7.2, bromothymol will therefore turn blue when brought in contact with fluid leaking from the amnion. A suitable indicator for this strong acid - strong base titration would be bromothymol blue (pH range 6.2 - 7.6) or phenol red (pH range 6.8 - 8.4). An aqueous solution of hydrochloric acid, HCl(aq), is a strong acid. Consider bromothymol blue (pH range 6.2 - 7.6) and phenol red (pH range 6.8 - 8.4) as possible indicators for this neutralisation reaction: A suitable indicator for this strong acid - strong base titration would be bromothymol blue (pH range 6.2 - 7.6) or phenol red (pH range 6.8 - 8.4). and Bromophenol Blue using a digital camera . Since bromophenol blue carries a slight negative charge at moderate pH, it will migrate in the same direction as DNA or protein in a gel; the rate at which it migrates varies according to gel density and buffer composition, but in a typical 1% agarose gel in a 1X TAE buffer or TBE buffer, bromophenol blue migrates at the same rate as a DNA fragment of about 300 base pairs, in 2% agarose as 150 bp. It changes from yellow at pH 3.0 to purple at pH 4.6; this reaction is reversible. BROMOPHENOL BLUE: In the pH scale, the pH value of the solution could be less than 4.0. Bromophenol blue (3,3,5,5-tetrabromophenolsulfonphthalein, BPB),[2] albutest[3] is used as a pH indicator, an electrophoretic color marker, and a dye. As CO2 is absorbed from the breath into the solution, forming carbonic acid, the solution changes color from green to yellow. The molecular weight of bromophenol blue is around 670 Daltons or grams per mole. Since the equivalence point for the titration (pH = 7) occurs within the pH range for the visible colour change of the indicator (the end point between pH 6.2 and 7.6), this indicator can be used for this titration. color change in this pH range. Bromophenol blue, Tetrabromophenolsulfonephthalein, is an acid-base indicator whose useful range as an indicator lies between pH 3.0 and 4.6. pH range (phenolphthalein) is 8.3 - 10.0 In the discussion above, we decided that we could use bromothymol blue or phenol red as indicators for the titration of NaOH(aq) (a strong base) with HCl(aq) (a strong acid) because these indicators change colour over a range of pH values that includes the pH of NaCl(aq) (the salt produced in the neutralisation reaction): At the equivalence point the only species in solution is NaCl(aq), bromothymol blue changes colour between pH 6.0 and 7.6, phenol red changes colour between pH 6.8 and 8.4. They work only in colorless solutions in which a color change can be observed and can only give an approximate pH value. Phenolphthalein is an indicator of acids (colorless) and bases (pink). Bromophenol blue is an acid phthalein dye. Reference: [1] Dhananasekaran S,Palanivel R,Pappu S. Adsorption of Methylene Blue, Bromophenol Blue, and Coomassie Brilliant Blue by -chitin nanoparticles. The deprotonation of the neutral form results in a highly conjugated structure, accounting for the difference in color. Used as a pH indicator, it changes color over a pH range from 3.0 (yellow) to 4.6 (blue). Uses of bromophenol blue indicator include testing for soap in unwashed biodiesel and glycerol. The approach utilizes purified BPB dye whose absorbance characteristics have been determined over a range of temperatures and salinities.
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