Albumin Assay Kits

Albumin is a hydrophilic simple protein mostly present in cells and body fluids. Plasma albumin (M.W. 69,000, pl 4.9) occupies approximately 56% - 60% of total plasma proteins. Plasma albumin is synthesized in the liver cells, plays an important role in maintaining blood osmotic pressure, and contributes the transfer of hydrophobic substances e.g. fatty acids, bilirubin, and thyroxine by binding them. Concentration of albumin in plasma is lowered in liver cirrhosis due to decreased biosynthesis, in malnutrition and pyrexial diseases due to increased consumption of albumin, and in renal damage due to secretion into urine. By measuring both albumin and total protein concentrations, the albumin-to-globulin ratio (A/G ratio) can be determined. The A/G ratio serves as a valuable marker for a range of conditions, including liver disease, kidney disease, nutritional disorders, multiple myeloma, and chronic inflammatory conditions.

In normal healthy subjects, excretion of plasma albumin into urine is very little (approx. 30 mg/day), but concentration of urinary albumin is increased in glomerulonephritis, nephritic syndrome, and diabetic nephropathy since albumin excretion into the urine is increased in renal diseases. It also sometimes increases in pyrexia, hypertension, congestive heart failure (CHF), and urinary tract infection (UTI). A transient increase of urinary albumin concentration is observed after hard exercise, physical work, high-temperature bath, mental excitement, stress, intake of much protein, and before menstruation even in healthy subjects and these are called physiological/functional/exercise proteinuria (albuminuria). Orthostatic proteinuria is sometimes observed in teenagers as well.

In humans, a rare congenital disorder called hypoalbuminemia, sometimes referred to as analbuminemia, is characterized by the presence of only very small amounts of albumin. Clinical symptoms include mild edema and moderate hypotension, with no evidence of liver dysfunction or proteinuria. Rat models for analbuminemia have been developed. A model analbuminemia rat has been established by Dr. Sumi Nagase in Sasaki Institute (Japan) which has been derived from Sprague-Dawley strain and is called Nagase analbuminemia rat (NAR).

Urinary albumin measurements are commonly performed using TIA method. Fujifilm Wako offers TIA reagents optimized for automated analyzers compatible with specimens from rats, mice, and monkeys. For applications requiring higher sensitivity, ELISA is recommended. Fujifilm Wako’s ELISA kits support a wide range of research needs, such as investigating the association between blood or urinary albumin levels and specific diseases, studying albumin biosynthesis in vitro, detecting contamination of FBS/FCS in biologically active substances derived from cell cultures, and monitoring albumin production as an indicator of success in liver cell or tissue transplantation in NAR. Fujifilm Wako also offers LabAssay™ Albumin, a biochemical assay kit based on the bromocresol green (BCG) method, providing a simple and rapid solution for measuring albumin in blood.

How to Choose Kits

Fujifilm Wako offers three product options tailored to different research needs:
i) Reagents for Automated Analyzers
ii) ELISA kits
iii) biochemical assay kits
Please note that the applicable sample types vary by product — refer to the sections below for further details.

i) Reagents for Automated Analyzers

Features

• Rapid measurement (10 minutes)
• Wide measurement range with excellent reproducibility
• Compatible with general-purpose automated biochemical analyzers

For details on analysis parameters, please contact us.

Appearance
Product Name	LBIS™ Mouse Urinary Albumin Assay Kit	LBIS™ Rat Urinary Albumin Assay Kit
Product No. (Package Size)	295-92701 (60 tests)	297-92901 (60 tests)
	291-92703 (250 tests)	293-92903 (250 tests)
Calibration curve range	6.17-500 μg/mL	6.17-500 μg/mL
Analysis sample	Mouse serum*/urine	Rat serum*/urine
Sample volume	6 μL	6 μL

Mouse and rat albumin control serum are available for quality control purposes.
* Since serum albumin concentrations are higher than those in urine, a dilution of approximately 10,000 to 1,000,000 is required.

ii) ELISA Kits

Features

• Enables rapid measurement
• Requires only a small sample volume
• Provides high measurement accuracy and excellent reproducibility
• Uses environmentally friendly preservatives
• Supplied as ready-to-use liquid reagents

iii) Biochemical Assay Kit

Features

• Results in approximately 20 minutes
• Requires only 2 μL of sample
• No dilution of blood samples required
• Blood A/G ratio can be calculated (when used in combination with LabAssay™ Total Protein, Code No. 295-98801)

Kit Performance

Example of Calibration Curve

Bovine Albumin Standard

Mouse Albumin Standard

Rat Albumin Standard