Novel atomizer source
High Performance Liquid Chromatography/Mass Spectrometry analysis of real-world biological substances in difficult matrices is often presented with problems with low signal to noise ratio, high limits of detection etc. To overcome this, expensive or difficult preparation or expensive technologies have to be used, raising the cost in time and money for such analyses. The scientists at the University of Tartu have devised a new and improved design for an electrospray inlet source nebulizer for an HPLC-MS interface that offers significant gain of signal, a raise in signal quality and a greater suppression of matrix effect as compared to ordinary atomizers at a lower costs.
Background
Spray atomizers are used in analytical chemistry to bring a liquid sample into gas phase so that it can be brought into the analysis region of a measuring device without too much of the solvent/eluent disturbing or masking the analytical signal. The critical parameters here are droplet size and ionization efficiency, which have an effect on the vaporization ratio of the droplets, etc.
There exists a wide range of applications in analytical chemistry where an atomizing interface is necessary. Case in point – electrospray ionization sources in LC/MS systems. These applications are often related to detecting traces of biological (and bio-similar) substances from difficult matrices such as water from natural sources, fruit and tissue. The problems with those are the complex interactions between the multitude of substances in the sample and the behaviour and characteristics of the analyte itself which tend to mask the signal and make an accurate analysis difficult.
The Solution
The team has modified a standard injection atomizer system design to enhance the atomization by introducing another stream of gas into the nozzle via a concentric array of capillaries (see more in international patent application no. WO2012146979). The exact geometry of the arrangement is the key here to obtain the smallest droplets (see Figure 1).
Intermittent concentric conical jets of gas and eluent combine to generate a so-called nano-mist that exhibits easier ionization and quicker vaporization which in turn results in a greater sensitivity of the detector. The atomizer can be used in many different liquid-vacuum interfaces, such as electrospray ionization sources (ESI), atmospheric-pressure ionisation sources (APCI), atmospheric- pressure photoionization sources (APPI), and the like in LC/MS systems. Of these, ESI are most used and versatile, being the de-facto standard in LC-MS interfaces in analysing biological matrixes, water etc.
This comparatively low-tech solution allows keeping any production and application costs low. By optimizing the gas flow in the capillaries one can easily regulate the detector signal-to-noise ratio to suit the sensitivity to the specific analyte while suppressing other signals. The system has been tested with some of the most common pesticides (Carbendazime, Thiabendazole, Imazalil, Methiocarbin) in some of the most difficult matrices, e.g. garlic and onion. Tests with standard Agilent LC-MS systems have shown up to a 10x lower limit of detection, and up to 50% less signal suppression from matrix effect.
The Offer
We offer a licensing and/or development cooperation model to develop the technology into a product or a part of one. The expected outcome is an enhanced atomizer as a modification to an existing system, a feature in a new system or a standalone (e.g. third party) upgrade suitable for selected systems, showing comparable or better results to competing, more expensive options.
The principles of managing IP generated during such a cooperation is open for discussion with licensing and assignment options available. Usually, UT would retain publication rights for research results with a 30 day refusal period for the commercial partner for any sensitive material
The team
The team behind the technology at the University of Tartu consists of specialists in the relevant areas, covering fields from analytical chemistry, LC-MS to fluidics. The head of the team is Anneli Kruve, Ph.D., with Koit Herodes, Ph.D., Ivo Leito, Ph.D, Rünno Lõhmus, Ph.D. and Ants Lõhmus, Ph.D. providing their expertise in their respective fields of expertise.
The team has significant scientific merit as well as experience in offering Contract Research services to companies.
Keywords
Electrospray, high performance liquid chromatography, mass-spectrometry, LC-MS, Mass spectroscopy, Ions, Nebulize, Mass Analyzer, Ionisation, Capillary, Nebulise, Spray, Ionization, Duct, Effluent, Inject, Atomize, Conduit, Emit, Atomise, Analyte, Cone.