[{"data":1,"prerenderedAt":-1},["ShallowReactive",2],{"doc-seo-621338-105":3,"detail-sidebar-cat-0-en-105":79,"doc-detail-621338-en":129},{"code":4,"msg":5,"data":6},0,"ok",{"site_id":7,"language":8,"slug":9,"title":10,"keywords":11,"description":12,"schema_data":13,"social_meta":72,"head_meta":74,"extra_data":76,"updated_unix":78},105,"en","biuret-protein-assay-determination-of-protein-concentration-by-biuret-method-expected-learning-outcomes","Biuret Protein Assay - Determination of Protein Concentration by Biuret Method - Expected Learning Outcomes","","Biuret Protein Assay determines protein concentration through the formation of a violet/blue color complex. Cu2+ ions in Biuret reagent react with amide groups (-NH) present in peptide bonds under basic pH, producing a color whose intensity is proportional to the number of participating peptide bonds. The protocol includes preparing a BSA standard (10 mg/ml), preparing Biuret reagent and NaOH solutions, incubating samples with the reagent, then measuring absorbance at about 540 nm and plotting a standard curve to calculate unknown protein levels.",{"@graph":14,"@context":71},[15,34,54],{"@type":16,"itemListElement":17},"BreadcrumbList",[18,23,27,31],{"item":19,"name":20,"@type":21,"position":22},"https://docshare.wps.com","Home","ListItem",1,{"item":24,"name":25,"@type":21,"position":26},"https://docshare.wps.com/document/","Document",2,{"item":28,"name":29,"@type":21,"position":30},"https://docshare.wps.com/document/exam/","Exam",3,{"item":32,"name":10,"@type":21,"position":33},"https://docshare.wps.com/document/biuret-protein-assay-determination-of-protein-concentration-by-biuret-method-expected-learning-outcomes/621338/",4,{"url":32,"name":10,"@type":35,"image":36,"author":41,"headline":10,"publisher":44,"fileFormat":47,"inLanguage":8,"description":12,"dateModified":48,"datePublished":48,"encodingFormat":47,"isAccessibleForFree":49,"interactionStatistic":50},"DigitalDocument",{"url":37,"@type":38,"width":39,"height":40},"https://docshare.wps.com/thumbnails/biuret-protein-assay-determination-of-protein-concentration-by-biuret-method-expected-learning-outcomes/621338.png","ImageObject",300,407,{"name":42,"@type":43},"Kyle","Person",{"url":19,"name":45,"@type":46},"DocShare","Organization","application/pdf","2026-10-20",true,{"@type":51,"interactionType":52,"userInteractionCount":22},"InteractionCounter",{"@type":53},"ViewAction",{"@type":55,"mainEntity":56},"FAQPage",[57,63,67],{"name":58,"@type":59,"acceptedAnswer":60},"What is the principle of the Biuret method for protein estimation?","Question",{"text":61,"@type":62},"Under basic pH, Cu2+ from Biuret reagent complexes with amide groups (-NH) formed from peptide bonds in proteins, producing a strong blue/violet color. The color intensity correlates with protein concentration.","Answer",{"name":64,"@type":59,"acceptedAnswer":65},"How is the standard curve created in this experiment?",{"text":66,"@type":62},"BSA standards of known concentrations are prepared, mixed with Biuret reagent, incubated, and their absorbance is measured (at about 540 nm). The absorbance values are used to plot the standard graph and calculate the concentration of the unknown sample.",{"name":68,"@type":59,"acceptedAnswer":69},"What reagents and solutions are required?",{"text":70,"@type":62},"Biuret reagent is prepared using CuSO4, sodium potassium tartrate, and 0.2 N NaOH. The experiment also uses 0.2 N NaOH, a BSA stock standard solution (10 mg/ml), and distilled water, along with glassware and a spectrophotometer.","https://schema.org",{"og:url":32,"og:type":73,"og:title":10,"og:site_name":45,"og:description":12},"article",{"robots":75,"canonical":32},"index,follow",{"doc_id":77,"site_id":7},621338,1792502422,{"code":4,"msg":80,"data":81},"success",[82,86,90,93,98,103,108,113,118,121,125],{"id":22,"doc_module":4,"doc_module_name":25,"category_name":83,"show_sort_weight":84,"slug":85},"Story & Novel",90,"story-novel",{"id":26,"doc_module":4,"doc_module_name":25,"category_name":87,"show_sort_weight":88,"slug":89},"Literature",80,"literature",{"id":33,"doc_module":4,"doc_module_name":25,"category_name":29,"show_sort_weight":91,"slug":92},70,"exam",{"id":94,"doc_module":4,"doc_module_name":25,"category_name":95,"show_sort_weight":96,"slug":97},5,"Comic",60,"comic",{"id":99,"doc_module":4,"doc_module_name":25,"category_name":100,"show_sort_weight":101,"slug":102},6,"Technology",50,"technology",{"id":104,"doc_module":4,"doc_module_name":25,"category_name":105,"show_sort_weight":106,"slug":107},7,"Healthcare",40,"healthcare",{"id":109,"doc_module":4,"doc_module_name":25,"category_name":110,"show_sort_weight":111,"slug":112},8,"Research & Report",30,"research-report",{"id":114,"doc_module":4,"doc_module_name":25,"category_name":115,"show_sort_weight":116,"slug":117},9,"Religion & Spirituality",20,"religion-spirituality",{"id":116,"doc_module":4,"doc_module_name":25,"category_name":119,"show_sort_weight":116,"slug":120},"World Cup","world-cup",{"id":122,"doc_module":4,"doc_module_name":25,"category_name":123,"show_sort_weight":122,"slug":124},10,"Lifestyle","lifestyle",{"id":126,"doc_module":4,"doc_module_name":25,"category_name":127,"show_sort_weight":94,"slug":128},19,"General","general",{"code":4,"msg":80,"data":130},{"doc_id":77,"user_id":131,"nickname":42,"user_avatar":132,"doc_module":4,"category_id":33,"category_name":29,"doc_title":10,"doc_description":12,"doc_content":133,"file_id":134,"file_url":135,"file_type":136,"file_size":137,"view_count":22,"is_deleted":4,"is_public":22,"is_downloadable":22,"audit_status":22,"page_count":99,"language":138,"language_code":8,"site_id":7,"html_lang":8,"table_of_contents":139,"faqs":140,"seo_title":141,"seo_description":12,"update_tm":142,"read_time":143,"preview_page_count":4},3985741905716,"https://ap-avatar.wpscdn.com/davatar_994ba38a5ba835b3df7d355c54d3ed8d","peptide bond  \n# Biuret reagentViolet color complex\n\n## DETERMINATION OFPROTEIN CONCENTRATIONBY BIURET METHOD\n\nStructure  \n\n| 2.1    | Introduction   | 2.4    | Procedure   |\n| --- | --- | --- | --- |\n|  | Expected Learning Outcomes   | 2.5    | Results   |\n| 2.2    | Principle   | 2.6    | Discussion   |\n| 2.3    | Materials Required   |  |  |\n| 2.1   |  INTRODUCTION   |  |  |\n\nA descent number of good and sensitive protein assay methods are available,however one of the simplest and most common is the Biuret Protein Assay.The Biuret method is based on the complexation of Cu²+to functional groupsin the protein's peptide bond.The determination of protein concentration is anessential technique in all aspects of protein studies and proteomics.Eachmethod has its own advantages and limitations and often it is necessary toobtain more than one type of protein assay for research applications.  \nProtein assays based on these methods are divided into two categories,(i)dye binding protein method and (ii)protein assays based on alkaline coppermethod.  \n### i.  Dye binding protein assay method\n\nThe dye binding protein assays are based on the binding of protein moleculesto Coomassie dye under acidic conditions.The binding of protein to the dyeresults in a spectral shift,the color of Coomassie solution changes from brown(absorbance maximum 465nm)to blue (absorbance maximum 610nm).Thechange in color density is read at 595nm and is proportional to the proteinconcentration.  \nii.Protein assays based on alkaline copper  \nIn the copper ion based protein assays,protein solutions are mixed with analkaline solution of copper salt,(cupric ions,Cu²+).The protein assay is basedon the interaction of cupric ions with protein in an alkaline solution and iscommonly referred to as the Biuret assay.The interaction of cupric ions (Cu²+)with protein results in a purple color that can be read at 540 nm.The amountof color produced is proportional to protein concentration.  \nIn spite of the availability of different methods of protein estimation,theapplication of the study is the point of concern for the study which you do.  \nExpected Learning Outcomes:After performing this experiment,you shall be able to  \n·explain the principle behind Biuret method;  \n·describe the composition of reagents used in Biuret method;  \n·plot the standard graph to measure protein concentration in a testsample;and  \n·able to distinguish between estimation of protein U.V absorption andBiuret method.  \n### 2.2PRINCIPLE\n\nBiuret is a small compound that forms when urea is heated allowing two ureamolecules to join.Urea molecules fused in this manner produce amide groups(-NH)at the center of the molecule which bind to cupric ions at a basic pH.The copper complexes that result from this interaction produce a strong bluecolor that can be measured with a spectrophotometer.Proteins also containamide groups.When an amino group and a carboxyl group join to form apeptide bond,the amino group(-NH₂)becomes an amide group(-NH).Atbasic pH,the proteins forms complex with copper ions.Because this reactionwas first observed with biuret,it is called the biuret reaction (Fig.2.1),andwhen this reaction is used to measure protein concentrations,it is called theBiuret Protein Assay.  \nThus,in this assay you will combine protein samples with Biuret Reagentwhich contains copper ions in a basic solution.The copper ions willcomplexwith the amide groups in the proteins to create a blue color that will bemeasured using a spectrophotometer.The intensity of the color formed isdirectly proportional to the number of peptide bonds participating in thereaction and thus in the amount of protein present.  \nViolet color complex  \nFig.2.1:Reaction of Biuret and copper complex,B.Biuret reagent reacts with analkaline solution of CuSO4 to form a violet chelate compound  \nThis relationship allows a standard curve to be created that is used tocalculate the concentration of protein in an unknown sample.  \n### 2.3 MATERIALS REQUIRED","cbCaiiThuQBVNMcA","https://ap.wps.com/l/cbCaiiThuQBVNMcA","pdf",1060620,"English","# DETERMINATION OFPROTEIN CONCENTRATIONBY BIURET METHOD\n## INTRODUCTION\n## PRINCIPlE\n## MATERIALS REQUIRED\n## PROCEDURE","[{\"question\":\"What is the principle of the Biuret method for protein estimation?\",\"answer\":\"Under basic pH, Cu2+ from Biuret reagent complexes with amide groups (-NH) formed from peptide bonds in proteins, producing a strong blue/violet color. The color intensity correlates with protein concentration.\"},{\"question\":\"How is the standard curve created in this experiment?\",\"answer\":\"BSA standards of known concentrations are prepared, mixed with Biuret reagent, incubated, and their absorbance is measured (at about 540 nm). The absorbance values are used to plot the standard graph and calculate the concentration of the unknown sample.\"},{\"question\":\"What reagents and solutions are required?\",\"answer\":\"Biuret reagent is prepared using CuSO4, sodium potassium tartrate, and 0.2 N NaOH. The experiment also uses 0.2 N NaOH, a BSA stock standard solution (10 mg/ml), and distilled water, along with glassware and a spectrophotometer.\"}]","Biuret Protein Assay - Determination of Protein Concentration by Biuret Method - Expected Learning Outcomes | PDF",1792465368,15]