Thiobarbiturate and fructosamine assays: significance and interest of the borohydride blank

Abstract

The acute-phase reaction (APR) induces the production by the liver of short-lived glycoproteins. The carbohydrate moiety of these proteins is thought to interfere with the thiobarbiturate (TBA) and nitroblue tetrazolium colorimetric tests which are used for assaying non-enzymatic glycosylation (NEG) of serum proteins. The aim of the present study was to assess the effect of the APR on the specificity of the colorimetric tests in non-diabetic and diabetic subjects. A positive correlation was found between C-reactive protein (CRP), an APR glycoprotein, and non-specific TBA reactivity as determined after borohydride reduction (BH4-resistant TBA, BR-TBA), both in non-diabetics (r = 0.61; P < 0.01) and diabetics (r = 0.68; P < 0.01). The BH4-sensitive specific TBA (SP-TBA) was not influenced by glycoproteins, and its increase in diabetics was correlated with the nitroblue tetrazolium assay (r = 0.89; P < 0.01). An independent effect of diabetes and APR on non-specific TBA was also demonstrated, suggesting an effect of hyperglycaemia on both protein glycation and glycosylation. TBA with borohydride reduction is an attractive tool for the study of complex glycoproteins in diabetes.

Raman Spectroscopy Provides a Powerful Diagnostic Tool for Accurate Determination of Albumin Glycation

“…Nevertheless, as detailed by Sacks [33], these methods are not widely used because of their lack of suitability for routine clinical laboratory application. For example, the aforementioned colorimetric assays suffer from lack of specificity [34] and are vulnerable to the presence of free glucose, uric acid or lipemia [35]–[37]. Furthermore, the development of monoclonal antibodies specific to glycated albumin [38], while beneficial in principle, has not caused a rise in the availability of commercial glycated albumin assays at this present time.…”

Comprehensive overview of human serum albumin glycation in diabetes mellitus

“…However, the above traditional methods have their own characteristics or drawbacks. For example, colorimetric analysis methods such as nitro-blue tetrazolium and thiobarbituric acid have high unspecificity[ 49 ]; fructosamine assays provide higher specificity and reliability[ 50 ]; HPLC method has a high sensitivity[ 41 ]; phenylborate-containing acrylamide gel electrophoresis method is time-consuming and not suitable for clinical measurement[ 51 ]. In recent years, electrochemical quantitative analysis methods with high sensitivity and specificity have also been developed[ 52 ].…”

Emerging trends in optical sensing of glycemic markers for diabetes monitoring

“…Several reagent-specific colorimetric methods, notably featuring thiobarbituric acid [20] and nitroblue tetrazolium [21], have also been used, but their high degree of non-specificity and interference from free glucose renders the less attractive for routine usage [22]. A number of the existing approaches were broadly used for glycated protein (or fructosamine) measurements and it is only recently that a significant thrust to develop and to standardize glycated albumin assays has taken place [14].…”