Affinity Selection-Mass Spectrometry (AS-MS)

Affinity Selection-Mass Spectrometry (AS-MS) is a revolutionary label-free biophysical technology dedicated to hit identification in early drug discovery, serving as a robust complement to traditional High-Throughput Screening (HTS). This cutting-edge approach directly identifies small molecule binders targeting therapeutic proteins without relying on reporter systems, enzymatic assays, or chemical modifications, making it ideal for intractable drug targets such as GPCRs, ion channels, protein-protein interaction (PPI) targets, and non-enzymatic proteins.

AS-MS hit screening operates by incubating target proteins with compound libraries, separating bound small molecules from non-specific binders via affinity selection, and identifying active binders with high-resolution mass spectrometry. This targeted workflow unlocks unique values for hit identification:

• Label-Free Detection: Eliminates interference from fluorescent tags or probe modifications, preserving native protein conformation and ensuring authentic target-ligand interactions for accurate hit discovery.
• High Sensitivity & Specificity: Captures weak to moderate affinity binders that may be missed by HTS, enriching a broader pool of potential hits and reducing false negative rates.
• Broad Target Compatibility: Adaptable to purified proteins, membrane proteins, and multi-subunit complexes, supporting hit screening for diverse drug targets across oncology, neurology, inflammation and metabolic diseases.
• Library Versatility: Compatible with small molecule libraries, fragment libraries, natural product libraries and peptide libraries, catering to customized hit screening demands.

As a core brand of STEMart, PharmaAnalytica delivers tailored AS-MS hit screening services for global biotech, pharmaceutical enterprises and academic research institutions. Leveraging advanced mass spectrometry platforms, automated sample processing systems and rigorous data analysis pipelines, we efficiently mine high-quality hit compounds from diverse compound libraries, accelerating the transition from target validation to lead optimization and overcoming the limitations of conventional functional screening in hit discovery.

Standard AS-MS Hit Screening Workflow

PharmaAnalytica follows a strict 4-phase standardized workflow for AS-MS hit screening, ensuring efficient, accurate and reliable identification of bioactive hit compounds:

1. Experimental Design & Optimization: Customize screening schemes based on target protein properties and client requirements, optimize incubation conditions, buffer systems and affinity separation parameters to maximize specific binding efficiency.
2. Library Incubation & Affinity Selection: Incubate target proteins with compound libraries using the ZX Bio automated liquid handling system; separate bound small molecules from unbound components via ultrafiltration, size exclusion or immunoprecipitation to enrich active binders.
3. Mass Spectrometry Detection & Data Acquisition: Subject enriched ligand samples to high-resolution mass spectrometry analysis, collect molecular data efficiently, and conduct preliminary quality control to filter invalid signals and ensure data reliability.
4. Hit Identification & Report Delivery: Analyze mass spectrometry data with professional bioinformatics software to identify positive hit compounds; conduct preliminary validation of binding activity, eliminate false positives, and deliver a comprehensive screening report with hit structures, binding information and follow-up recommendations.

PharmaAnalytica's Technology Platfom

Advantages of PharmaAnalytica's AS-MS Hit Screening Services

Customized Screening Solutions

Tailor workflows for different target types, library scales and research objectives, meeting personalized hit screening needs for various drug discovery projects.

Integrated Automation & Quality Control

Combines automated sample processing with strict multi-level QC, ensuring data reproducibility and screening reliability throughout the process.

Efficient Turnaround Time

Streamlined experimental workflow and professional technical team accelerate hit discovery progress, shortening the cycle of early drug discovery.

Seamless Follow-Up Support

Provide subsequent hit validation, structure-activity relationship (SAR) analysis and lead optimization services, building a closed loop for early drug discovery.

Backed by STEMart's strong R&D strength and PharmaAnalytica's expertise in early drug discovery, our AS-MS hit screening services provide a label-free, high-efficiency solution for identifying novel bioactive hits. We empower clients to overcome bottlenecks in traditional screening, unlock high-value drug candidates, and drive breakthroughs in innovative drug development.