Hydrodynamic DNA Shearer

Plaque Picker

High Capacity Shaker

Template Preparation Machine

Flow Through Micro-Centrifuge

Plasmid Preparation Machine

Thermocycler

Capillary Electrophoresis

Oligonucleotide Synthesizer

Arrayer

Scanner

This instrument was developed in Pat Brown's lab in the Biochemistry Department. 

The micro arrayer is a high-capacity system developed to monitor the expression of many genes in parallel. The instrument is used to hybridize cDNA drops onto coated slides, thus forming cDNA microarrays which are then scanned for fluorescence. By using steel quills, cDNA solution is dipped from 384-well plates and dotted onto up to 48 slides. The quill is positioned to be able to draw sufficient liquid from only 5 ul of the solution for delivery to all of the slides. The arraying of the dots on the slides allow eleven 384-well plates to be dotted onto a centimeter square. The head that contains the quills holds up to 16 of them, speeding up the rate at which the slides can be dotted. A plate can currently be micro-arrayed onto 48 slides in about 76 minutes when each sample is going to be dotted once; each sample can optionally be dotted one to three times. The slides that are used are silylated (specially coated) to produce a clearer scanned image. 

Microarrays are prepared by high-speed robotic printing of complementary DNAs onto glass slides. They are used for quantitative expression measurements of their corresponding genes. Because of the small format and high density of the arrays, hybridization volumes of 2 microliters can be used. This enables detection of transcripts in probe mixtures which were derived from 2 micrograms of total cellular messenger RNA. So far, differential expression measurements of 45 Arabidopsis genes have been made by means of this type of parallel, two-color fluorescence hybridization. We are planning to use the arrayer for other genomic applications. 

Thus the arrayer prints microarrays which are then scanned by a laser for the fluorescence data. For parallel expression, the arrayer followed by the scanner replaces the need for a sequencer by simple confirmation instead of resequencing. 

Performance and Specifications:

• Size of samle area on slide: 36x18 mm

 
• Typical dot spacing: 200 microns

 

For dots per sample:	1	2	3
Maximum number of slides:	48	48	48
Maximum 384-well plates:	27	13	9
Maximum samples/slides (dots):	10368	9984	10368
Single sample to 48 slides (seconds):	76	103	135
Each plate of 384 samples (minutes):	30	41	54
All plates of 384 samples (hours):	13.5	8.9	8.1

 

Drawings for this instrument are available from Pat Brown's lab