Interferences in the Assay of Serum Albumin Using the Bromcresol Green Lab Report

Interferences in the Assay of Serum Albumin Using the Bromcresol Green Indicator - Lab Report Example Albumin's molecular structure was reported from research in the past 30 years. Albumin's clinical importance was discussed, explaining that the test for Albumin is not a marker for any specific disease, while it is an important indicator for the physiological condition of the body. It was explained that an abnormally high result for Albumin needs to resolved and at face-value is considered a spurious result. The cause of elevated albumin levels are usually a result of accompanying serum proteins, acute phase infections, elevated immunoglobulins(found in multiple myeloma), or autoimmune issues. The BCG method was thoroughly researched. It is a valuable test for screening, when performing mass analysis of blood work in large clinical laboratories. It has fallen out of favor with laboratory clinicians for fear that the test can mask hypoalbunemia and low readings. BCG is an acid-base indicator, its acid to base color change is from yellow to blue, with a range in pH from 4.2-5.6. The de tection of hypoalbunemia is always important to a physician. Low Albumin readings are indicative of a deteriorating condition in the body. An alternative to the BCG indicator is Bromcresol Purple(BCP), also an acid–base indicator. A comparison studies have been performed of the two methods. When compared to a benchmark analytic method Capillary Zone Electrophoresis(CZE), the positive bias for BCG was 3.77, while BCP faired much better with 0.67. Our experiment produced linear curves needed in detection and quantification of albumin concentrations. We demonstrated the effect on accompanying globulins elevating the result in BCG determinations of albumin. We also showed that time, reagent concentration and wavelength of absorbance significantly affect albumin readings. We bring to consideration for further testing the affect of pH on the test. Background and Literature review In clinical medical laboratories the testing for serum albumin, globulins and total protein are standard procedures, performed daily. Theses assays may also be requested STAT or on an emergency basis for patients suffering a crisis situation. The techniques for determining albumin and total protein are numerous and varied. Most clinical laboratories perform three routine three routine examinations; 1) Total Protein(TP) 2) Serum Albumin(Alb) 3) Serum Globulins Human blood contains both a cellular and liquid portion. Albumin is the most abundant protein in the human circulatory system1 and contributes 80% to providing colloid osmotic pressure2. Albumin is chiefly responsible for maintenance of the blood's acid-base balance, commonly referred to as pH3. In mammals it is synthesized by the liver as a preproalbumin. It undergoes a two cleavage processes before release into the body's circulation in its final form. It has been determined that the half-life of a albumin molecule is 19 days4.. Figure 1: Molecular Cleavage of albumin from preproalbumin->proalbumin->albumin Figure 2: The classical perception of the Albumin molecule Peters, T., Jr. (1985). Serum Albumin. Adv. Protein Chem.37; 161-2455 Figure 3: Primary, secondary and tertiary structure (Carter and Ho, 1994) . 6 This picture shows the bovine albumin amino acid sequence. The BSA molecule is made up of three homologous domains (I, II, III) which are divided into nine loops (L1-L9) by 17 disulphide bonds. The loops in each domain are made up of a sequence of large-small-large loops forming a triplet. Each domain in turn is the product of two subdomains (IA, IB, etc.). The primary structure of albumin is unusual among extracellular proteins in possessing a single