The Original 96Well Format

The original MADGE format[3] uses a two-dimensional plastic former in conjunction with one glass plate coated with gamma-methacryloxypropyltrimethooxysilane (sticky silane). The plastic former contains a 2-mm-deep, 100 x 150-mm rectangular ''swimming pool.'' Within the pool, there are ninety-six 2-mm cubic ''teeth'' (well formers) in an 8 x 12 array with 9-mm pitch directly compatible with 96-well plates. The array is set on a diagonal of 18.4° relative to the long side of the ''pool,'' which is parallel to the eventual direction of electropho-resis, giving gel track lengths of 26.5 mm (Fig. 1A). The gel former is placed horizontally, acrylamide mix poured into the pool, and the glass plate overlaid (Fig. 1B). After the gel has set, the glass plate is prized off, bearing its open-faced 96-well gel. It should be noted that although the diagonal-array approach may appear complex, many users have noted that this is the simplest gel preparation and sample tracking system they have ever used. Additionally, the human eye/brain is extremely good at pattern recognition and the small-scale user, once accustomed, is not obliged to use image

Fig. 1 Outline of components of MADGE system. (A) Schematic plan view of 96-well MADGE. Direction of electrophoresis is marked with an arrow relative to well A1. (B) Steps a-d for pouring a single 96-well PAGE MADGE gel. Gels can also be poured in batches in a purpose-built box, or gel mix can be poured through the small gap at one end into a preassembled sandwich of gel former and glass plate.

(C) Ninety-six-pin passive replicator—essential for loading of high-density (384-768 well) MADGE gels. Either 8- or 12-channel pipettes or 96-pin devices can be used for 96-well gels. Air displacement rather than passive pins must be used for submerged gels.

(D) ''Dry'' box gel stack frames and ''dry'' gel boxes for multiple ''dry'' box gel electrophoresis. (View this art in color at www.dekker.com.)

Fig. 1 Outline of components of MADGE system. (A) Schematic plan view of 96-well MADGE. Direction of electrophoresis is marked with an arrow relative to well A1. (B) Steps a-d for pouring a single 96-well PAGE MADGE gel. Gels can also be poured in batches in a purpose-built box, or gel mix can be poured through the small gap at one end into a preassembled sandwich of gel former and glass plate.

(C) Ninety-six-pin passive replicator—essential for loading of high-density (384-768 well) MADGE gels. Either 8- or 12-channel pipettes or 96-pin devices can be used for 96-well gels. Air displacement rather than passive pins must be used for submerged gels.

(D) ''Dry'' box gel stack frames and ''dry'' gel boxes for multiple ''dry'' box gel electrophoresis. (View this art in color at www.dekker.com.)

analysis software. A 26.5-mm track length (2 x 4 diagonal of array) such as in Fig. 1A or greater such as the 2 x 6 diagonal in Fig. 3 (see section below on higher-resolution MADGE), using Polyacrylamide gel matrix, is efficient for many post-PCR analyses involving simple band pattern recognition. We also use agarose MADGE gels anchored on a hydrophilic plastic such as GelBond for checking long PCR products. Polyacrylamide MADGE gels are robust, reusable, directly stackable for storage or use, and fully compatible with industry-standard PCR microplates, thus minimizing procedural information transfers and enabling direct 96-channel pipetting. However, considerable advantage is gained even with 8- and 12-channel pipettes.

Short track length/run time, compactness, and scalability with hand-sized robust slab gels accessible for direct human interaction are additional benefits of MADGE. Startup costs are minimal, so ''third-world'' laboratories can also apply the system. Essentially, any analysis which can be reduced to short tracks (e.g., <3 cm) gains the throughput advantages. One technician can process

10-100 gels (960-38,400 tracks) per day according to the application and the MADGE implementation in use. Typical applications, in many laboratories worldwide, have been for allele-specific PCR and restriction digest checking post-PCR, for single-nucleotide genotyping in many samples in parallel in genetic epidemiological (''DNA bank'') research. Such MADGE-based approaches have been used extensively in our own laboratory (e.g., Ref. [4]) and in other laboratories (e.g., Refs. [5,6]). Another laboratory implemented complete genome mapping using high-throughput PCR from radiation hybrid cell lines combined with 96-well reusable MADGE-checking gels.

Getting Started With Dumbbells

Getting Started With Dumbbells

The use of dumbbells gives you a much more comprehensive strengthening effect because the workout engages your stabilizer muscles, in addition to the muscle you may be pin-pointing. Without all of the belts and artificial stabilizers of a machine, you also engage your core muscles, which are your body's natural stabilizers.

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