Albumin Quantification Made Easy: Working with Bethyl’s ELISA Kits

Few proteins shape blood plasma as profoundly as albumin. Its concentration responds sensitively to changes in various organs – from kidney damage (albuminuria) and the secretory activity of hepatocytes to leakage indicators in the retina, blood–brain barrier, or lungs [1]. Accordingly, the detection of albumin holds great importance across diverse fields: in the food industry, it is essential to ensure minimal albumin levels to prevent allergic reactions, while in vaccine production, excessively high albumin concentrations may increase the risk of anaphylactic shock [2].

A variety of methods are available for the detection of albumin — among them, ELISA has proven to be a particularly robust and reproducible technique. It can be applied to numerous matrices, including serum, plasma, cerebrospinal fluid, urine, milk, or BALF (bronchoalveolar lavage fluid). With clearly structured protocols, consistent documentation, and kits available for different species, the albumin ELISAs from our partner Bethyl Laboratories provide a reliable foundation for confidently comparing data from preclinical models, organoid systems, or quality control studies [3].

These topics await you:

1) Albumin in brief: Structure, Binding, and Functions

2) Quantifying Albumin with Bethyl ELISAs

3) Why Choose Bethyl Albumin ELISAs

Albumin in brief: Structure, Binding, and Functions

Albumin is the most abundant plasma protein in humans, present in the blood at particularly high concentrations. It is synthesized in the liver, consists of approximately 580–590 amino acids (≈ 66 kDa), and functions as an ampholyte – meaning it can reversibly bind both negatively and positively charged molecules. As a result, albumin performs a wide range of essential tasks: it transports bilirubin, free fatty acids, riboflavin, metal ions, and drugs, while also contributing to the stabilization of blood pH [4].

In biomedical research, particularly in mouse models, albumin serves as a sensitive marker for organ function and tissue damage. In nephrology, it is used as an indicator of albuminuria (e.g., UACR) and reflects STAT1-dependent inflammatory processes in models such as cast nephropathy. Beyond the bloodstream, albumin is also employed as a marker of tissue injury: in cases of retinal vascular leakage or in the lungs, albumin levels in BALF reliably indicate the extent of the lesion [1].

Quantifying Albumin with Bethyl ELISAs

In everyday laboratory work, one factor matters most when measuring albumin: reliability. The albumin ELISAs from Bethyl Laboratories are designed to provide a streamlined workflow while delivering robust, reproducible data. Pre-coated plates, well-defined reagents, and clearly structured manuals minimize preparation time. The procedure remains consistent across various sample types — including serum, plasma, cerebrospinal fluid, milk, and urine — allowing for reliable series measurements without the need to adjust the protocol each time [3].

A few practical key details make implementation in the lab straightforward: each well uses 100 µl, and measurements are performed in duplicates. The kits employ a standard curve ranging from 0.69 to 500 ng/ml (Fig. 1). The curve shown is exemplary — for each assay, an individual 4-parameter logistic (4-PL) curve is generated from the supplied standards. Recommended starting dilutions for sample preparation are provided and have proven effective in quickly reaching the optimal measurement range. Signal detection is performed as an endpoint measurement at 450 nm — an established standard that easily integrates into existing analysis workflows [3].

Albumin_ELISAs_Fig1 — **Figure 1: Exemplary standard curve (***Mouse Albumin ELISA E99-134*)*. A new curve should be generated for each plate; values may vary between runs [2].*

Another advantage of the Bethyl Laboratories Albumin ELISAs is the broad range of available kits: in addition to human samples, equivalent versions are offered for mouse, rat, pig, and bovine samples. The procedure remains nearly identical across species, making it easy to switch between models while ensuring a high degree of data comparability.

Product	Product Number	Price
Human Albumin ELISA Kit	E88-129	850 €
Mouse Albumin ELISA Kit	E99-134	850 €
Bovine Albumin ELISA Kit	E11-113	850 €
Rat Albumin ELISA Kit	E111-125	850 €
Pig Albumin ELISA Kit	E101-110	850 €

Practical guidance on wash steps and plate handling is clearly presented, supporting accurate execution. This helps minimize background signals and reliably maintain high reproducibility of measurements [2].

Why Choose Bethyl Albumin ELISAs

Bethyl Laboratories combines a robust assay design with clear and transparent documentation. The well-established sandwich format, featuring a biotinylated detection antibody and a separate streptavidin-HRP step, enables highly sensitive signal detection [2]. The assays also excel in specificity: the Bovine Albumin ELISA generates a concentration-dependent signal exclusively for bovine serum albumin, while bovine IgG, IgA, IgM, transferrin, and human albumin produce only background signals (Fig. 2) [2].

Albumin_ELISAs_Fig2 — **Figure 2: Specificity of the (***Bovine Albumin ELISA Kit*)*. Tested against bovine IgG, IgA, IgM, bovine transferrin, and human albumin [2].*

A distinctive feature of the Bethyl kits is their fully integrated production: all steps — from animal husbandry and immunization to development, manufacturing, and validation — take place in a single location. Combined with close collaboration with leading scientists and an ever-expanding target portfolio, this ensures seamless process control. This reduces sources of variation, such as lot-to-lot differences, and guarantees reproducible results across multiple runs [5].