TargetEx has extensive experience in protein engineering and expressing gene sequences across various expression systems as well as in assay development and HT screening. 

We have developed proprietary technologies (e.g. RefoldAll™) to increase the efficiency of drug discovery and development. Commercially, TargetEx offers clients ‘off the shelf’ services and collaborative research and development.

We understand the importance of confidentiality and communication in exploring and operating research projects. We encourage direct scientist to scientist communication at all stages in order to provide timely feedback on the progress of the project. We believe that our suite of advanced protein and screening facilities can deliver cost-effective solutions throughout your developmental efforts.

Drug Discovery Services

The drug discovery support services stem from our capability to express the molecular target in an appropriate expression system.

Target Protein Expression

We apply a lentiviral expression system or the traditional selection methods for recombinant cell line generation. The activity of the molecular target is a must.


Target focused library generation and virtual screening

Target-focused compound libraries are designed to interact with an individual protein target or target families. Target-focused libraries are used for assay validation followed by assay development; rapid hit generation when initiating new drug discovery projects; or hit validation generated around the newly identified active compounds in a screening campaign.

For further details see: Target-focused library generation

Assay development and screening

Assay development and screening services support our partner’s projects in the early phase of drug discovery. We can offer fragment base, biochemical assays, and cellular assays covering most of the major target classes. Assay development and screening are supported by our in-house recombinant protein production and cell culture facilities. MT and HT assays are conducted in 96-well and 384-well plate formats. Plate handling is fully robotized using proper liquid handling devices and integrated readers. Assay read-outs include fluorescence, luminescence, absorbance, and radioactivity. Besides Target Ex’s available assays, the client’s assays can be accommodated in our facilities. The screening quality is continuously monitored by well-established statistical parameters (z’-factor, S/B ratio) and reported to the client as part of the study report delivered periodically or at the end of the campaign. 

Protein expression services: Xpress Xpert- Integrated service from problem to solution

XpressXpert™ is a comprehensive modular protein expression service which delivers purified recombinant proteins according to client-supplied protein sequence data. Our integrated services include the following modules:
* Target-oriented choice of expression system. We have used the following host cells to produce recombinant proteins: E. coli, yeast, insect (Sf9 or Hi5) and mammalian cells
* Codon optimization according to the host cell codon usage in order to improve the expression level
* Subcloning into expression vector
* Production of the biomass using shaking cultures
* Protein purification development
* Quality control: recombinant protein identification by LC-MS and biological activity measurement

Protein purification development

TargetEx offers protein purification development services for industrial customers. We can perform the experiments in pilot laboratory scale using only up-scalable methods (e.g. deep filtration, cross flow filtration, various column chromatography methods, etc.) to fulfill the analytical requirements. After technology transfer, the customers can easily upscale the production. TargetEx has previous experience on the following areas:
* Subunit vaccine purification
* VLP (Virus Like Particle) purification
* Bacteriophage purification
* Alternative strategies for therapeutic protein purification

Services for protein analytics

Our recombinant proteins are not just bands on an SDS PAGE gel! Their activity is checked by relevant biochemical assays and/or we can use biophysical methods for protein structural studies.
The list of available protein analytical services:
* Immunoblot
* LC MS/MS identification
* Various functional assays
* ELISA assay
* Endotoxin assay
* Protein concentration measurement by BCA assay
* DNA content determination by a fluorometric method or using specific qPCR DNA probes
* DNase or RNase activity assay
* Binding assay by SPR
* CD measurement
* Phage display
* Differential scanning calorimetry (DSC)
* Differential scanning fluorometry (DSF)
* Isothermal titration calorimetry (ITC)

ISO 9001 certified protein production services:

In 2018 due to customer demand, we introduced the ISO9001 quality management system. Now our development protocol reflects the current ISO regulations: First we elaborate the technology to produce and purify the target protein. After that we upscale the production up to the protein amount required by the customers.  When these steps are completed SOPs (Standard Operating Procedures) are created and the customer directed product is registered into the quality management system.  Consequently, our production line strictly follows the rules of ISO 9001. You can read our Quality Policy here.


TargetEx Ltd.

H-2120 Dunakeszi Madách Imre u 31/2.


Zsolt Lőrincz, PhD

Chief Executive Officer


Tel.: +36-30-352-9529

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