Interaction of biomolecules sequentially deposited at the same location using a microcantilever-based spotter

Abstract

A microspotting tool, consisting of an array of micromachined silicon cantilevers with integrated microfluidic channels is introduced. This spotter, called Bioplume, is able to address on active surfaces and in a time-contact controlled manner picoliter of liquid solutions, leading to arrays of 5 to 20-microm diameter spots. In this paper, this device is used for the successive addressing of liquid solutions at the same location. Prior to exploit this principle in a biological context, it is demonstrated that: (1) a simple wash in water of the microcantilevers is enough to reduce by >96% the cross-contamination between the successive spotted solutions, and (2) the spatial resolution of the Bioplume spotter is high enough to deposit biomolecules at the same location. The methodology is validated through the immobilization of a 35mer oligonucleotide probe on an activated glass slide, showing specific hybridization only with the complementary strand spotted on top of the probe using the same microcantilevers. Similarly, this methodology is also used for the interaction of a protein with its antibody. Finally, a specifically developed external microfluidics cartridge is utilized to allow parallel deposition of three different biomolecules in a single run.

Technological Challenges and Future Issues for the Detection of Circulating MicroRNAs in Patients With Cancer

“…The coupling of several targets on the same detection platform remains a scientific challenge with strong clinical potential. One interesting option for multiple functionalization (with resolutions in the order of 10 μm) could be the use of microcontact printing or tools for drop delivery, derived from MEMS technology and capable in theory of sampling and depositing very small volumes of solution (Berthet-Duroure et al, 2008; Salomon et al, 2012). Such experiment would be a first step toward multiplexing detection systems.…”

Multiplexed Remote SPR Detection of Biological Interactions through Optical Fiber Bundles

“…A soft microcantilever (Bioplume V6, LAAS, Toulouse, France), a polymeric replication of a previously developed silicon microcantilever [39,40] fabricated by 3D-printing of a DS-3000 photoresist (DWS, Thiene, Italy) with a Dilase 3D printer (Kloe SA, St Mathieu de Tréviers, France) [41,42], was used to deposit microdrops of solutions on the microstructured face of the bundle. Details on the polymeric microcantilever conception are reported in the electronic Supplementary Materials ( Figure S4).…”

Scanning Probe Microscope-Based Fluid Dispensing

“…With an applied voltage range of 0 to 210 V, droplets of 5 to 40 μm diameters with volumes 20 fL to 14 pL were deposited [90]. The deposition of polymers, biological solutions, and metal particles were also demonstrated [91,92]. The aspiration of liquid by electrowetting was possible with this device [93].…”