New Approach to Oligonucleotide Microarrays Using Zirconium Phosphonate-Modified Surfaces

Abstract

A new approach to oligonucleotide arrays is demonstrated that utilizes zirconium phosphonate-derivatized glass slides. The active slides are prepared by binding Zr(4+) to surfaces terminated with organophosphonate groups previously deposited using either Langmuir-Blodgett or self-assembled monolayer methods. Oligonucleotide probes modified with a terminal phosphate bind strongly to the active zirconium phosphonate monolayer, and arrays for detecting fluorescent targets have been prepared using commercial spotting and scanning instruments. Preferred binding to the surface of the terminal phosphate of the modified probes instead of the internal phosphate diester groups is demonstrated and shown to yield increased fluorescence intensity after hybridization with labeled targets. A significant decrease in background signal is achieved by treating the slides with bovine serum albumin after spotting and before hybridization. A further increase in fluorescence after hybridization is observed when using a poly-guanine spacer between the probe oligomer and the terminal phosphate. Combining these modifications, an intensity ratio of nearly 1000 is achieved when comparing 5'-phosphate-modified 33-mer probes with unmodified probes upon hybridization with fluorescent targets.

Ti4+‐Immobilized Magnetic Composite Microspheres for Highly Selective Enrichment of Phosphopeptides

“…So, each metal ion coordinates to more than one phosphate molecule and each phosphate group also binds to more than one metal ion. Therefore, the extremely strong binding of the titanium ions provides a very stable, well-defi ned interface of phosphate-Ti 4 + , where the located titanium ions are very active and can further react with other exposed phosphate groups, [ 49 ] such as the phosphate groups of phosphopeptides.…”

Metal Phosphonates Applied to Biotechnologies: A Novel Approach to Oligonucleotide Microarrays

“…An inorganic system that we have found to meet these requirements is a series of thin films of metal organophosphonates and organophosphates. [41][42][43][44][45][46][47] In the solid-state, many examples form layered structures with organic sheets separating continuous inorganic networks of metal ions coordinated by the phosphonate or phosphate oxygen atoms. [48] An example is the layered Zr(O 3 PC 6 H 5 ) 2 shown in Figure 4.…”

Robust phosphoproteome enrichment using monodisperse microsphere–based immobilized titanium (IV) ion affinity chromatography

“…In this case, the MO6 are octahedrally coordinated by oxygen atoms, with the three oxygens of each phosphonate bound to three different zirconium ions 31 . Notably, the unique coordination of Zr 4 + or Ti 4 + with the phosphate/phosphonate group has been shown to have a richness of applications, including DNA microarrays 32 , protein microarrays 33 and self-assembled monolayers 34 . We recently developed a new generation of IMAC for phosphopeptide enrichment [35][36][37][38][39] by using the unique property of Zr(IV) or Ti(IV) phosphate/ phosphonate chemistry.…”