ProteinChip technology arrays

The ProteinChip System from Ciphergen Biosystems uses patented SELDI (Surface-Enhanced Laser Desorption/Ionization) ProteinChip technology to rapidly perform the separation, detection, and analysis of proteins at the femtomole level directly from biological samples. ProteinChip Systems use ProteinChip Arrays which contain chemically (cationic, anionic, hydrophobic, hydrophilic, etc.) or biochemically (antibody, receptor, DNA, etc.) treated surfaces for specific interaction with proteins of interest. Selected washes create on-chip, high-resolution protein maps. This protein mass profile, or reten-tate map of the proteins bound to each of the ProteinChip Array surfaces, is quantitatively detected in minutes by the ProteinChip Reader. 

In contrast, ProteinChip technology allows the detailed analysis of A(3 fragments and their modifications (22). Peptides are captured on arrays coated with anti-Ap Ab, washed to remove nonspecifically bound fragments, and finally detected by SELDI-TOF MS. The resolution of the technique allows the discrimination of peptides of similar mass and modified products, e.g., oxidized peptides versus native peptides, which differ by only 16 Da. ProteinChip technology has been used extensively to detect Af> fragments in various samples, including cell culture supernatants, serum, plasma, and cerebrospinal fluid (CSF) (21-23). 

Fig. 2. Capture of A(3 using Ab-coated ProteinChip arrays. Preactivated arrays with exposed active sites are shown in (A). Ab are covalently bound to the array via amine groups (B). Exposed active sites are blocked using Tris-containing buffer (C). Samples are added to the array, incubated for 1 1 h (D), and washed to remove nonspecifically bound proteins (E). EAM is applied to each spot (F), and the array is introduced into the ProteinChip reader where the laser is fired onto the chip surface. Proteins retained on the array surface are subsequently resolved via TOF-MS, which displays the mass-to-charge value and signal intensities of each protein (G, H). (Adapted from ProteinChip technology training course, Bio-Rad Laboratories.)...

ProteinChip technology [15] special array surfaces are used to selectively retain entire subsets of proteins directly, and in a single step from biological samples. Thus, in contrast to HPLC-MS, which combines elution chromatography with MS, SELDI-MS combines retention chromatography with MS. 

Reddy G, Dalmasso EA. SELDI ProteinChip(R) array technology protein-based predictive medicine and drug discovery applications. J Biomed Biotechnol 2003 2003 237-241. 

The use of SELDI ProteinChip array technology in 29. renal disease research. Methods Mol. Med. 2003, 86,... 

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