Workflow of MRM/PRM Quantitative Analysis

MRM (Multiple Reaction Monitoring) and PRM (Parallel Reaction Monitoring) are widely used quantitative analysis techniques in modern mass spectrometry, applied extensively in biomedical research, drug development, and clinical diagnostics. They enable quantitative analysis of specific target molecules with high sensitivity and selectivity, providing researchers with powerful analytical tools.

 

MRM Analysis Process

1. Sample Preparation

(1) Extraction

The extraction of target molecules from the sample is the primary step in MRM analysis, commonly achieved through liquid-liquid extraction and solid-phase extraction. Different sample matrices can affect the extraction efficiency of target molecules.

 

(2) Concentration

To improve analytical sensitivity, extracted samples often need to be concentrated to remove interfering substances.

 

2. Mass Spectrometry Parameter Setup

(1) Ionization

Techniques such as Electrospray Ionization (ESI) or Matrix-Assisted Laser Desorption/Ionization (MALDI) are used to convert target molecules into ions.

 

(2) Reaction Selection

In MRM, selecting precursor and characteristic product ions is crucial to ensure accurate detection of target molecules in complex matrices.

 

3. Data Acquisition

During mass spectrometric analysis, MRM periodically monitors selected precursor and product ion pairs to obtain quantitative information about the target molecules.

 

4. Data Analysis

Specialized software analyzes the acquired mass spectrometric data to calculate the concentration of target molecules, comparing them with standard curves.

 

PRM Analysis Process

1. Sample Preparation

The sample preparation process for PRM is similar to that for MRM, with a focus on optimizing extraction and concentration steps to ensure the quality and quantity of target molecules.

 

2. Mass Spectrometry Parameter Setup

(1) Full Ion Scanning

PRM employs a Full-Scan monitoring mode that provides more comprehensive information, suitable for the analysis of unknown or complex samples.

 

(2) Selection of Characteristic Ions

The process of selecting characteristic ions in PRM requires more caution to ensure that the chosen ions adequately represent the target molecules.

 

3. Data Acquisition

A key advantage of PRM is its ability to provide qualitative analysis during the quantitative process, offering a more comprehensive profile of molecular characteristics.

 

4. Data Analysis

In the data analysis phase, PRM quantitatively compares sample and standard profiles based on characteristic ion spectra, often requiring more complex data processing and calculations.

 

Comparison and Applications

MRM and PRM each have their strengths. MRM is characterized by high throughput and sensitivity, making it suitable for large-scale sample analyses; while PRM offers more comprehensive molecular information, ideal for in-depth analysis of complex samples. Both techniques play crucial roles in biomarker screening, drug metabolism research, and proteomics.

 

The MRM and PRM quantitative analysis processes provide powerful tools for biological research. By carefully designing experimental workflows and data analysis strategies, researchers can more accurately reveal the molecular characteristics in biological samples, supporting data-driven research in related fields.