Protein Microarray Service

Background

What is Protein Microarray?

Protein Microarray, or protein chip, is a high-throughput analysis tool that lets you check out gene expression at the protein level and explore how proteins interact on a large scale, covering things like antigen-antibody, DNA-protein, and RNA-protein interactions. This technique involves sticking thousands of unique proteins onto a solid surface like a slide or microplate to catch the target, much like classic ELISA assays. The core principles include protein expression and purification, getting proteins onto the array surface, and spotting protein interactions. These arrays are generally split into analytical and functional types, plus there’s a reverse phase option where tissue or cell lysates are dabbed onto slides.

Fig. 1. Procedures of proteome microarray construction and application. (Qi, et al., 2019)

Types of Protein Microarray

Protein microarrays come in three main types, each offering unique applications in proteomics to study protein interactions and functions comprehensively:

• Analytical Protein Microarrays : These are like antibody microarrays focused on detecting proteins. They can use direct labeling or a sandwich assay format with reporter antibodies to spot target proteins. They’re great for analyzing complex protein mixes, measuring binding affinity, specificity, and expression levels.
• Functional Protein Microarrays : These arrays pack full-length functional proteins or protein domains. These microarrays help researchers dive into the biochemical activities of whole proteomes, checking out connections like protein-protein, protein-DNA, protein-RNA, protein-lipid, and protein-small molecule interactions. They’re key players in both basic research and clinical work, backing up studies on proteomes and post-translational tweaks in different organisms.
• Reverse-Phase Protein Microarrays (RPAs) : This type has a different setup where tissue or cell lysates are sampled onto slides. They’re used to analyze samples from different states directly, like tissue or cell extracts, with high sensitivity and precision. They’re especially handy for studying changes in specific proteins and modifications during disease progression, playing a key role in biomarker discovery.

Fig. 2. Common formats used for the preparation of protein microarrays. (Berrade, et al., 2011)

What is Protein Microarray Service Used for?

Microarray technology is a powerful tool with significant applications due to its ability to handle large data volumes with accuracy. Here’s how it is utilized in several critical fields:

• Protein Interaction Studies

Microarray technology enables swift identification and examination of protein interactions, crucial for comprehending complex cellular signaling and molecular processes. Microarray technology helps scientists discover the structure of protein complexes, understand how proteins interact dynamically, and figure out the control mechanisms inside protein networks.

• Large-Scale Protein Analysis

This technology excels at analyzing numerous proteins simultaneously, allowing for the investigation of thousands in just one experiment. This drastically improves research efficiency and output. It’s transformative for analyzing extensive protein expression patterns, aiding disease research, drug discovery, and biomarker identification.

• Antibody Specificity Screening

Microarray tools streamline antibody research, helping to find and assess specific antibodies with ease. By placing target antigens on a microarray, researchers can swiftly check how specific and strong antibodies are, making the selection process faster.

• Biomarker Screening

Microarray technology is crucial in finding and confirming biomarkers. By examining how proteins are expressed in various disease conditions, scientists can uncover biomarkers useful for diagnosis, prognosis, and monitoring treatment, which is vital for progressing personalized and precise medical approaches.

• Drug Target Validation and Screening

Microarray technology significantly contributes to confirming drug targets and spotting potential drug candidates. By studying how drugs affect protein behavior and expression, it aids in refining how drugs are designed and assessing their effectiveness and safety.

Service Procedure

Platforms

Our specialized protein microarray platform is equipped with high-precision chip spotters, high-resolution scanners, automated liquid handling systems, and environmental controls to ensure experimental sensitivity and stability. By integrating advanced surface modification, non-specific adsorption suppression, multi-mode detection (such as fluorescence, chemiluminescence, and SPR), alongside high-throughput data collection and bioinformatics analysis, we deliver efficient, accurate, and customized protein microarray services to meet the demands of research and drug development.

Service Contents

Professional Microarray Technology

• Antibody microarrays: Used for identifying antibodies that bind to proteins.
• Antigen microarrays: Employed to examine how specific antibodies are and to assess immune reactions.
• Whole-proteome microarrays: large-scale protein function studies and marker discovery.
• Reversed-phase microarray: Analysis of protein expression in samples to aid disease research.
• Peptide microarrays: for epitope mapping and vaccine development.
• Glycosyl microarray: Study the interaction of sugar molecules with proteins and antibodies.

Protein Function Analysis Service

Our microarray services offer extensive solutions for protein function analysis. These include examining protein-protein interactions, screening small molecules that interact with proteins, determining antibody specificity and strength, identifying new therapeutic targets, validating target functions, assessing drug efficacy, and studying alterations in protein activity. These services not only accelerate the drug discovery and development process, but also provide scientific basis for personalized medicine and precision therapy, deeply reveal the complexity of protein function, and promote the progress of biomedical research.

High Throughput Detection Service

Our microarray services employ advanced techniques like fluorescence and chemiluminescence for precise data collection, ideal for high-throughput processes such as large-scale screenings and biomarker research. This approach ensures quick and precise examination of protein samples in antigen-antibody specificity, host-microbe relationships, and protein-protein interactions. We support critical areas like disease diagnostics, pathogen investigations, autoimmune disorders, neurodegenerative conditions, and cancer, significantly aiding precision medicine.

Microarray ELISA Service

Our microarray service significantly increases the throughput and sensitivity of the assay with an upgraded ELISA microarray technology, which is particularly suitable for large-scale quantitative biomarker detection. This service not only supports multiple ELISA methods, including direct, indirect, sandwich and competitive ELISA, to meet different detection needs, but also enables simultaneous analysis of hundreds of different proteins, reducing cost and effort, and providing strong support for biomarker discovery and validation.

Our Advantages

• Leading Technology Platform and Experienced Team : Our state-of-the-art technological framework is backed by a team of seasoned professionals, ensuring top-tier delivery.
• High Sensitivity and Specificity : Achieved through advanced surface modification and detection techniques, we guarantee accurate results.
• High Throughput Capability : Our systems support large-scale protein screening and detection, accelerating the research process significantly.
• Comprehensive Data Analysis Support : We provide extensive support for data analysis to extract meaningful insights from complex datasets.
• Customized Solutions : Tailored solutions to meet the diverse needs of our clients, offering personalized approaches to unique challenges.
• Data Reliability and Repeatability : Automated platforms coupled with stringent quality control measures ensure the consistency and reliability of experimental results.

Case Study

Background

This project involves screening interaction peptides between two proteins using a peptide array. The array is created based on peptide sequences provided by the client, each being 12 amino acids long. In total, 227 distinct peptides are synthesized onto a single chip. The array is then exposed to biotin-labeled proteins P1 and P2. P1 interacts with the newly created peptide chip, while P2 interacts with a regenerated version of the chip. To detect biotin signals, HRP-Streptavidin is applied; the presence of color indicates protein-peptide binding, while an absence of color indicates no binding.

Methods

The experimental method mainly includes three steps: synthesis of peptide array, incubation of peptide array with protein and regeneration of peptide chip. During the synthesis process, FMOC-amino acids are automatically transferred to the activated membrane to form a peptide array, which is completed through a series of washing and deprotection steps. The incubation procedure involves treating peptide chips with blocking solution, incubating them with biotin-labeled proteins, then detecting binding sites with HRP-streptavidin, and imaging. Peptide chip regeneration removes bound proteins through denaturation and acid treatment for reuse.

Results

In this project, we performed peptide array experiment for screening interaction peptides and two proteins.
Some peptides on the peptide array chip can interact with the tested protein, combined with image analysis, 9-11, 13-17, 30-32, 64-76, 162-168, 171, 200-209 peptide spots on the peptide array have obvious color development effects with P1 protein; the peptide spots in these regions 13-15, 31-33, 64-74, 161-168, 200-208 on the regenerated polypeptide array have obvious color development effect with P2 protein.

Fig. 3. The Hybridization signal intensity image between the peptide chip and the P1 protein.

Fig. 4. The Hybridization signal intensity image between the peptide chip and the Protein P2.

FAQs

• Q: What are the minimum sample requirements for microarray services?

  A: Sample requirements depend on array type and experimental design, for example, protein sample sizes are generally 1-10 µg, which will be detailed at protocol confirmation.

• Q: Do you support customized services?

  Yes, we support full process customization from protein fragment design to microarray construction, and we can adapt the experimental design and data analysis to the customer's research objectives.

• Q: How does protein microarray technology compare to traditional ELISA?

  Protein microarray technology surpasses traditional ELISA in throughput and sensitivity. It can analyze thousands of proteins at once, unlike ELISA, which is limited to a few targets per assay. This method also uses less sample and reagents, which enhances efficiency and data yield.

• Q: Are microarray services compatible with intricate biological samples like serum and plasma?

  Absolutely, our microarray service is tailored to handle complex biological fluids, including serum and plasma. It effectively identifies numerous proteins and biomarkers in these samples, providing crucial information for diagnosing diseases and conducting research.

References:

• Qi H.; et al. Proteome microarray technology and application: higher, wider, and deeper. Expert Rev Proteomics. 2019;16(10):815-827.
• Berrade L.; et al . Protein microarrays: novel developments and applications. Pharm Res . 2011;28(7):1480-1499.