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A versatile snap chip for high-density sub-nanoliter chip-to-chip reagent transfer.

Li H, Munzar JD, Ng A, Juncker D - Sci Rep (2015)

Bottom Line: Misalignment, which for direct transfer ranged from 150-250 μm, was reduced to <40 μm for double transfer.The versatility of the snap chip is illustrated with a 4-plex homogenous enzyme inhibition assay analyzing 128 conditions with precise timing.The versatility and high density of the snap chip with double transfer allows for the development of high throughput reagent transfer protocols compatible with a variety of applications.

View Article: PubMed Central - PubMed

Affiliation: 1] Biomedical Engineering Department, McGill University, Montréal, QC, H3A 0G1, Canada [2] McGill University and Genome Quebec Innovation Centre, McGill University, Montréal, QC, H3A 0G1, Canada.

ABSTRACT
The coordinated delivery of minute amounts of different reagents is important for microfluidics and microarrays, but is dependent on advanced equipment such as microarrayers. Previously, we developed the snap chip for the direct transfer of reagents, thus realizing fluidic operations by only manipulating microscope slides. However, owing to the misalignment between arrays spotted on different slides, millimeter spacing was needed between spots and the array density was limited. In this work, we have developed a novel double transfer method and have transferred 625 spots cm(-2), corresponding to >10000 spots for a standard microscope slide. A user-friendly snapping system was manufactured to make liquid handling straightforward. Misalignment, which for direct transfer ranged from 150-250 μm, was reduced to <40 μm for double transfer. The snap chip was used to quantify 50 proteins in 16 samples simultaneously, yielding limits of detection in the pg/mL range for 35 proteins. The versatility of the snap chip is illustrated with a 4-plex homogenous enzyme inhibition assay analyzing 128 conditions with precise timing. The versatility and high density of the snap chip with double transfer allows for the development of high throughput reagent transfer protocols compatible with a variety of applications.

No MeSH data available.


Related in: MedlinePlus

Misalignment of spots following direct and double transfer methods, with a schematic illustrating the consequences of angular misalignment.(a) Box plots of spatial misalignment in each of 16 nitrocellulose pads on one assay slide (1024 spots) using the direct transfer method. Nitrocellulose pad numbers are the same as indicated in Fig. 3(b) Schematic illustration on how mirroring of the transfer reagents on the assay slide amplifies the angular misalignment α between the slide and the inkjet XY stages by a factor 2. The box plots in (a) and (c) show the upper and lower quartile as box edges, the median value is indicated by the box centerline, and the whiskers show the range of the data. (c) Box plots showing the misalignment for spots of each of 16 nitrocellulose pads on one slide (1024 spots) using the double transfer method. (d) Schematic illustration of double transfer method to overcome the angular misalignment. (e,f) Distribution of misalignment of 3072 spots from three independent experiments: (e) the direct transfer method, with 20 μm bins, and (f) the double transfer method, with 5 μm bins.
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f4: Misalignment of spots following direct and double transfer methods, with a schematic illustrating the consequences of angular misalignment.(a) Box plots of spatial misalignment in each of 16 nitrocellulose pads on one assay slide (1024 spots) using the direct transfer method. Nitrocellulose pad numbers are the same as indicated in Fig. 3(b) Schematic illustration on how mirroring of the transfer reagents on the assay slide amplifies the angular misalignment α between the slide and the inkjet XY stages by a factor 2. The box plots in (a) and (c) show the upper and lower quartile as box edges, the median value is indicated by the box centerline, and the whiskers show the range of the data. (c) Box plots showing the misalignment for spots of each of 16 nitrocellulose pads on one slide (1024 spots) using the double transfer method. (d) Schematic illustration of double transfer method to overcome the angular misalignment. (e,f) Distribution of misalignment of 3072 spots from three independent experiments: (e) the direct transfer method, with 20 μm bins, and (f) the double transfer method, with 5 μm bins.

Mentions: Misalignment of the direct and double transfer methods was quantified by measuring the distance between pairs of overlaid spots of transferred and sessile drops. The misalignment was rendered visible by using fluorescently labeled antibodies as reagents; the sessile and transferred antibodies were labeled with green and red fluorescent dyes, respectively, Fig. 3. When using the direct transfer method, a systematic misalignment was observed between spots of first and second reagents along the horizontal axis, ranging from ~150 μm at the top of the slide to ~250 μm at the bottom, as shown in Fig. 4a and SI Fig. 2a-b.


A versatile snap chip for high-density sub-nanoliter chip-to-chip reagent transfer.

Li H, Munzar JD, Ng A, Juncker D - Sci Rep (2015)

Misalignment of spots following direct and double transfer methods, with a schematic illustrating the consequences of angular misalignment.(a) Box plots of spatial misalignment in each of 16 nitrocellulose pads on one assay slide (1024 spots) using the direct transfer method. Nitrocellulose pad numbers are the same as indicated in Fig. 3(b) Schematic illustration on how mirroring of the transfer reagents on the assay slide amplifies the angular misalignment α between the slide and the inkjet XY stages by a factor 2. The box plots in (a) and (c) show the upper and lower quartile as box edges, the median value is indicated by the box centerline, and the whiskers show the range of the data. (c) Box plots showing the misalignment for spots of each of 16 nitrocellulose pads on one slide (1024 spots) using the double transfer method. (d) Schematic illustration of double transfer method to overcome the angular misalignment. (e,f) Distribution of misalignment of 3072 spots from three independent experiments: (e) the direct transfer method, with 20 μm bins, and (f) the double transfer method, with 5 μm bins.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4493572&req=5

f4: Misalignment of spots following direct and double transfer methods, with a schematic illustrating the consequences of angular misalignment.(a) Box plots of spatial misalignment in each of 16 nitrocellulose pads on one assay slide (1024 spots) using the direct transfer method. Nitrocellulose pad numbers are the same as indicated in Fig. 3(b) Schematic illustration on how mirroring of the transfer reagents on the assay slide amplifies the angular misalignment α between the slide and the inkjet XY stages by a factor 2. The box plots in (a) and (c) show the upper and lower quartile as box edges, the median value is indicated by the box centerline, and the whiskers show the range of the data. (c) Box plots showing the misalignment for spots of each of 16 nitrocellulose pads on one slide (1024 spots) using the double transfer method. (d) Schematic illustration of double transfer method to overcome the angular misalignment. (e,f) Distribution of misalignment of 3072 spots from three independent experiments: (e) the direct transfer method, with 20 μm bins, and (f) the double transfer method, with 5 μm bins.
Mentions: Misalignment of the direct and double transfer methods was quantified by measuring the distance between pairs of overlaid spots of transferred and sessile drops. The misalignment was rendered visible by using fluorescently labeled antibodies as reagents; the sessile and transferred antibodies were labeled with green and red fluorescent dyes, respectively, Fig. 3. When using the direct transfer method, a systematic misalignment was observed between spots of first and second reagents along the horizontal axis, ranging from ~150 μm at the top of the slide to ~250 μm at the bottom, as shown in Fig. 4a and SI Fig. 2a-b.

Bottom Line: Misalignment, which for direct transfer ranged from 150-250 μm, was reduced to <40 μm for double transfer.The versatility of the snap chip is illustrated with a 4-plex homogenous enzyme inhibition assay analyzing 128 conditions with precise timing.The versatility and high density of the snap chip with double transfer allows for the development of high throughput reagent transfer protocols compatible with a variety of applications.

View Article: PubMed Central - PubMed

Affiliation: 1] Biomedical Engineering Department, McGill University, Montréal, QC, H3A 0G1, Canada [2] McGill University and Genome Quebec Innovation Centre, McGill University, Montréal, QC, H3A 0G1, Canada.

ABSTRACT
The coordinated delivery of minute amounts of different reagents is important for microfluidics and microarrays, but is dependent on advanced equipment such as microarrayers. Previously, we developed the snap chip for the direct transfer of reagents, thus realizing fluidic operations by only manipulating microscope slides. However, owing to the misalignment between arrays spotted on different slides, millimeter spacing was needed between spots and the array density was limited. In this work, we have developed a novel double transfer method and have transferred 625 spots cm(-2), corresponding to >10000 spots for a standard microscope slide. A user-friendly snapping system was manufactured to make liquid handling straightforward. Misalignment, which for direct transfer ranged from 150-250 μm, was reduced to <40 μm for double transfer. The snap chip was used to quantify 50 proteins in 16 samples simultaneously, yielding limits of detection in the pg/mL range for 35 proteins. The versatility of the snap chip is illustrated with a 4-plex homogenous enzyme inhibition assay analyzing 128 conditions with precise timing. The versatility and high density of the snap chip with double transfer allows for the development of high throughput reagent transfer protocols compatible with a variety of applications.

No MeSH data available.


Related in: MedlinePlus