Adding function to characterization: Combining mass spectrometry with surface plasmon resonance

Abstract

Since Sir J.J. Thomson of the Cavendish Laboratory at the University of Cambridge constructed the first mass spectrometer (then called a parabola spectrograph) at the turn of the last century, mass spectrometry (MS) has become the most ubiquitous analytical technique in use today. It represents a powerful tool in the study of all substances, because it provides more information about the composition and structure of a substance from a smaller amount of sample than any other analytical technique. It is also a powerful quantitative tool. Femtograms (10 15 g) of carcinogenic pesticide residues can be quantitated and identified in foodstuffs, whereas a genetic abnormality can be characterized from mere femtomole (10 15 mol) quantities of a protein.

A survey of the year 2002 commercial optical biosensor literature

“…While Biacore technology is still employed primarily to study proteins, antibodies, receptors, peptides, 399-466 and oligonucleotides, it is increasingly used to characterize extracellular matrix components, 548-590 small molecules, 591-627 lipids, 628-671 carbohydrates and self-assembled monolayers. [717][718][719][720][721][722][723][724] In addition, biosensors are now more commonly used in food science, [700][701][702][703][704][705][706][707][708][709] in combination with mass spectrometry, [710][711][712][713][714][715][716] in clinical studies, [725][726][727][728][729][730] and in studying complex biological systems such as fibrils and cells. [731][732][733][734][735][736][737][738][739] Forty-seven articles described studies performed using Affinity Sensors' IAsys instruments (www.affinity-sensors.…”

Surface Plasmon Resonance/Mass Spectrometry Interface

“…In this respect, matrix-assisted laser/desorption ionization (MALDI)-MS seems to be the perfect complement. Not only does it offer all the advantages related to the determination of molecular masses of biomolecules as is presented in a wealth of scientific literature but it is also tolerant to functionalized hydrogel surfaces, which should allow the direct analysis of bound species on the sensor chip surface. , Therefore, both techniques have been applied in parallel, but there have also been several efforts to integrate SPR and MS synergistically. ,− For this combination, the analyte is either eluted from the SPR chip and respotted onto the MS target, ,, or the SPR chip (mostly known from Biacore) is taken from its holder and refitted into a custom-made MS target . While the first method keeps the biosensor chip reusable, but is hampered by time- and sample-consuming transfer steps, the second is more direct, but involves currently the destruction of the sensor chip and some manufacturing.…”