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Updated: Aug 8, 2026
Development and Validation of an Ultrasensitive Single Molecule Array Digital Enzyme-linked Immunosorbent Assay for Human Interferon-α
Published on: June 14, 2018
Self-assembled monolayer-based piezoelectric crystal immunosensor for the quantification of total human
1Institute of Material Research and Engineering, National University of Singapore, Block S7 Level 3, 10 Kent Ridge Crescent, 119260, Singapore.
Insights
This study introduces a novel piezoelectric (Pz) immunosensor for accurately measuring total human immunoglobulin E (IgE) in serum. The developed Pz immunosensor demonstrates high precision and reliability, correlating well with existing commercial tests.
Area of Science:
- Biosensors
- Analytical Chemistry
- Immunotechnology
Background:
- Accurate quantification of total human immunoglobulin E (IgE) is crucial for diagnosing allergic diseases.
- Existing methods for IgE detection may have limitations in precision, cost, or complexity.
- Development of sensitive and reliable immunosensors is an active area of research in diagnostics.
Purpose of the Study:
- To develop and validate a piezoelectric (Pz) immunosensor for the quantitative detection of total human IgE in serum samples.
- To evaluate the performance characteristics of the Pz immunosensor, including sensitivity, precision, and accuracy.
- To compare the Pz immunosensor's performance against established commercial diagnostic kits.
Main Methods:
- Fabrication of a piezoelectric immunosensor using a 10 MHz AT-cut gold-coated crystal resonator.
- Immobilization of anti-human IgE antibodies onto the resonator surface via self-assembled monolayers (SAMs).
- Quantification of total human IgE in serum samples within a specific concentration range (5-300 IU/ml).
Main Results:
- The Pz immunosensor achieved high precision with a coefficient of variation (CV) less than 8%.
- Results from 28 patient serum samples showed strong agreement with two commercial kits (FAST Test and Pharmacia-CAP), with correlation coefficients of 0.94 and 0.90, respectively.
- The sensor demonstrated reusability up to five times without significant loss of activity and exhibited 3-5 times less non-specific binding compared to conventional cross-linking methods.
Conclusions:
- The developed piezoelectric immunosensor offers a precise and reliable method for quantifying total human IgE in serum.
- The sensor's performance is comparable to commercial diagnostic kits, suggesting its potential for clinical application.
- The use of self-assembled monolayers (SAMs) enhances sensor performance by improving surface structure and reducing non-specific binding, while also allowing for sensor regeneration and reuse.
Abstract:
This work presents a piezoelectric (Pz) immunosensor for the quantification of total human IgE in serum samples. The anti-human IgE is deposited on the surface of the 10 M Hz AT-cut gold coated crystal resonator by self-assembled technique, and serves as a receptor layer. The highly ordered self-assembled monolayers (SAMs) ensure well-controlled surface structure and offer many advantages to the performance of the sensor. The fabricated Pz sensor can quantitatively detect human serum IgE in the range of 5-300 IU/ml with high precision (CV < 8%). A total of 28 patient serum samples are detected by the Pz sensor, and the results agree well with those given by two commercially provided test kits (Total IgE FAST Test, Pharmacia-CAP). The correlation coefficients are 0.94 between FAST and Pz sensor, and 0.90 between CAP and Pz sensor, respectively. After regeneration with urea and glycine buffer the coated crystal can be reused five times without appreciable loss of activity. Compared with conventional cross-linking methods, nonspecific binding caused by the SAM binding method is three to five times less.
