Biochip technologyb consists in measuring an interaction between a probe (protein, antibody) grafted on a solid support (glass slide, silicon disc) and a target (protein) previously labelled or not (fluorophore,…).
The main stages for the implementation of antibody biochips are as follows:
- Deposit: two types of deposits exist either by contact, or by noncontact. With the current systems, the size of the spots is about 100 to 300 µm diameter and in our facilities we currently work with the MicroGrid spotter from BioRobotics. We’ll also be able soon to use in routine our new nanoarrayer, BioplumeTM.
- The support of deposit and immobilization system: One of the major problems in the preparation of protein biochips is the choice of the support which allows ensuring the immobilization of proteins and the preservation of their three-dimensional configuration, a crucial condition to evaluate affinities with its molecular partners (Angenendt et al, 2003 ; Sakanyan, 2005).
For better preserving these biological properties, a physical trapping, a covalent bond or an affinity binding are better adapted (see Sakanyan, 2005 for the various types of laying-up system). Thus, optimizations were realized either to increase the intensity of the signal, or to decrease the background noise, in order to increase the sensitivity (Seurynck-Servoss et al, 2007). New immobilisation systems are also available with the use of dendrimers, their principle lying on the addition of a spacer of dendrimer type, between the support and the antibody (Trévisiol et al., 2003). We could use at MicroBioChips anykind of these different supports.
- Quality of molecules spotted: commercial antibodies are mostly used for antibody biochips (Haab et al, 2001). Other molecules (aptamers, ankryrins …) which mimic the antibody effects and improve their stability, specificity, and their affinity on biochips are also developed (Wingren and Borrebaeck, 2006). The access to the contain being usually expensive, new approaches aimed at synthesizing the proteins directly on biochips have been developed but have to be optimized for a routine use (He et al, 2008 ; Ramachandran et al, 2008). (Seurynck-Servoss et al, 2007).
As we built a real expertise in protein array, we are able to provide you with tailor made services using commercial or home made proteins – antibodies.
- System of revelation: Currently, most of antibody biochips platforms use systems of revelation with fluorescence. These approaches allow a limit of detection from nanomolar to fentomolar range, a concentration which is sufficient to detect minority proteins in precious clinical samples. (Ingvarsson et al, 2006). Thus, it is possible to detect minority proteins in precious clinical samples.
Other methods of detection without labelling, such as the SPR (Surface Plasmon Resonance), are promising but not very widespread.
MicroBioChips has an extensive background with Cy3 (green) and Cy5 (red) dies for fluorescence revelation. In addition, results are revealed with the microarray Scanner InnoScan 700 from Innopsys.
- Quantification & analysis: Main efforts were set up for the management of the data resulting from the analyses on biochips (Wilkins et al, 2006) but efforts remain to be made to implement standardized procedures for the management of the data (quantification, standardization…). MicroBioChips use Mapix and MicroVigene Softwares to perform the microarrays analysis.
- Deposit: two types of deposits exist either by contact, or by noncontact. With the current systems, the size of the spots is about 100 to 300 µm diameter and in our facilities we currently work with the MicroGrid spotter from BioRobotics. We’ll also be able soon to use in routine our new nanoarrayer, BioplumeTM.
- The support of deposit and immobilization system: One of the major problems in the preparation of protein biochips is the choice of the support which allows ensuring the immobilization of proteins and the preservation of their three-dimensional configuration, a crucial condition to evaluate affinities with its molecular partners (Angenendt et al, 2003 ; Sakanyan, 2005).
For better preserving these biological properties, a physical trapping, a covalent bond or an affinity binding are better adapted (see Sakanyan, 2005 for the various types of laying-up system). Thus, optimizations were realized either to increase the intensity of the signal, or to decrease the background noise, in order to increase the sensitivity (Seurynck-Servoss et al, 2007). New immobilisation systems are also available with the use of dendrimers, their principle lying on the addition of a spacer of dendrimer type, between the support and the antibody (Trévisiol et al., 2003). We could use at MicroBioChips anykind of these different supports.
- Quality of molecules spotted: commercial antibodies are mostly used for antibody biochips (Haab et al, 2001). Other molecules (aptamers, ankryrins …) which mimic the antibody effects and improve their stability, specificity, and their affinity on biochips are also developed (Wingren and Borrebaeck, 2006). The access to the contain being usually expensive, new approaches aimed at synthesizing the proteins directly on biochips have been developed but have to be optimized for a routine use (He et al, 2008 ; Ramachandran et al, 2008). (Seurynck-Servoss et al, 2007).
As we built a real expertise in protein array, we are able to provide you with tailor made services using commercial or home made proteins – antibodies.
- System of revelation: Currently, most of antibody biochips platforms use systems of revelation with fluorescence. These approaches allow a limit of detection from nanomolar to fentomolar range, a concentration which is sufficient to detect minority proteins in precious clinical samples. (Ingvarsson et al, 2006). Thus, it is possible to detect minority proteins in precious clinical samples.
Other methods of detection without labelling, such as the SPR (Surface Plasmon Resonance), are promising but not very widespread.
MicroBioChips has an extensive background with Cy3 (green) and Cy5 (red) dies for fluorescence revelation. In addition, results are revealed with the microarray Scanner InnoScan 700 from Innopsys.
- Quantification & analysis: Main efforts were set up for the management of the data resulting from the analyses on biochips (Wilkins et al, 2006) but efforts remain to be made to implement standardized procedures for the management of the data (quantification, standardization…). MicroBioChips use Mapix and MicroVigene Softwares to perform the microarrays analysis.