Our high-quality services depend on the best instrumentation on the market, and optimized setups for each individual machine. We can thus provide you with the information you need, as fast as possible.
Below you will find a list of the analysis we perform and the instruments we use for each.
Please contact us, if you need additional information about our methods and instrumentation.
Quantitative amino acid analysis of purified or total protein content
The protein mixture or purified protein sample is subject to hydrolysis, thus creating free amino acids. IEX-HPLC then analyzes these with post-column ninhydrin derivatization. The method accurately identifies and quantifies up to 20 amino acids and calculates the total protein content from the summed amino acid amounts.
We use an amino acid standard mixture to calibrate the instrument and also apply a NIST BSA standard to assess each batch run’s precision and accuracy. Finally, we run a standard amino acid solution for every five samples to correct ninhydrin activity.
Sodium Dodecyl Sulfate–Polyacrylamide 1D and 2D Gel Electrophoresis (SDS-PAGE)
This protein separation method uses a polyacrylamide gel as a medium and SDS for denaturation. After denaturation, the proteins have a negative charge, which migrates towards an anode (+). Larger molecules are restrained more than smaller molecules in the gel, thus separating them based on their size.
SDS-PAGE separation can be either One Dimensional (1D) or Two Dimensional (2D):
Enzyme-Linked Immunosorbent Assay (ELISA)
The immunological, plate-based assay measures and quantifies molecules, such as antibodies, peptides, and proteins.
In a ‘sandwich ELISA,’ the 96-well microtiter plate is coated with a capture antibody that binds the sample antigen (e.g., protein). Hereafter, a detecting antibody binds the antigen. A secondary antibody binds and cleaves an added substrate through its linked enzyme, thus leading to a detectable signal. The signal depends on the antigen amount.
Electrospray Ionization (ESI)
The ionization technique transforms ions of proteins and peptides from a liquid solution to a gaseous state before mass spectrometric detection. ESI Mass Spectrometry (ESI-MS) has high sensitivity and robustness, thus making it well-suited for non-volatile molecules and complex sample solutions.
Liquid Chromatography Mass Spectrometry (LC-MS & LC-MS/MS)
An HPLC separates the peptides and proteins (in liquid solution) according to chemical properties like hydrophobicity, size, and charge. The components are released from the stationary phase into the mobile phase and subsequently detected and analyzed in the mass spectrometer (MS). If the mixture is subject to tandem mass spectrometry (MS/MS), the first MS selects precursor ions by their mass (m/z), fragments them, and then detects them as product ions in the second MS.
Combining LC-MS with UV detection is also possible, thereby achieving UV trace chromatogram, MS ion current chromatogram, and MS spectra. This method is known as UV HPLC analysis.
NanoLC-MS/MS
A variant of LC-MS/MS with flow rates in the nanoliter/min range. NanoLC-MS/MS has a very long analysis time due to low flow rates. The system can thus only run smaller sample amounts but has higher sensitivity than the conventional LC-MS/MS setup.
SWATH LC-MS/MS
SWATH mass spectrometry is a data-independent acquisition (DIA) technique for detecting and quantifying all detectable compounds in a complex sample. Only the SCIEX TripleTOF instrument performs this analysis.
Multiple Reaction Monitoring (MRM LC-MS/MS)
Technique especially suited for quantification of specific, single proteins of particular interest (HCPs). MRM has high sensitivity and specificity, thus making it perfect for targeted analysis of a set of low-level proteins, even if they are only ppm-level abundant.
High-Performance Liquid Chromatography (HPLC analysis)
Form of column chromatography, where the sample solution in solvent (mobile phase) pumps through the column (stationary phase) at high pressure. The technique separates and identifies molecules based on their chemical properties. You will often use a UV or fluorescent detector in cases without an HPLC coupled to the mass spectrometer.
Reversed-Phase (RP-HPLC)
Most commonly used HPLC type with a non-polar stationary phase and an aqueous, polar mobile phase. In RP-HPLC, hydrophobic molecules interact with the stationary phase, whereas hydrophilic molecules elute first.
Size Exclusion (SEC-HPLC)
Type of HPLC that separates molecules based on their molecular size. The column packing with delicate, porous beads allows for separating small and big molecules since the smaller molecules can enter the pores. Thus, they move slower than larger molecules that cannot interact and enter the pores.
Ion Exchange (IEX-HPLC)
Type of HPLC that separates ionizable molecules based on their net charge. After loading the protein sample on the column, a washing step removes impurities before proteins elute from the column with a change in pH or a salt gradient.
Hydrophilic Interaction Liquid Chromatography (HILIC)
HILIC is an alternative HPLC mode with a polar stationary phase and an aqueous mobile phase, often as a gradient from a high percentage of organic solvent to a high ratio of the aqueous solvent. HILIC is especially useful for separating polar compounds, such as glycosylated proteins and released glycans.
Automated robotics for multi-step sample handling
Robust and reproducible sample preparation is a critical element in the high-quality analysis of biologics. Therefore, top-of-the-line pipetting robotics are applied together with in-house developed procedures to secure fast and consistent sample preparation.