Typical applications of the DMF1000 Polishing the Patch Pipettes It is well known that the proper fire polishing of patch pipettes is the single most important factor for forming a stable giga-seal in patch clamp recording. This is even more important than the type of glass capillary used. Difficulties often arise in forming giga-seals because the polishing of patch pipettes using a conventional low magnification microforge is inadequate. However, since the DMF1000 uses a 40X long-working distance objective, pipette polishing is much more accurately controlled. Pipettes polished using the DMF1000 achieve excellent stable giga-seals with a wide variety of cells. Both whole cell patch pipettes and single channel patch pipettes can be conveniently polished with the DMF1000 to the highest quality and reproducibility achievable with any microforge. For the single-channel patch clamp pipettes the pipette needs to be pre-coated with Sylgard 184 before polishing. For this procedure the user can follow a simple and effective coating method described previously (Li, 1999) ProfessionalGrade Microscope MICROFORGES, PULLERS, The W30 professional-grade microscope is a best-seller in universities, medical schools, and reseach laboratories. Equipped for performance, its features include titaniumfinished DIN or Semi-Plan optics and a 30-year anti-fungal coating. The W30 is the choice for superior performance at a great price. W30S-LED W30ST-LED 503513 Binocular Microscope Trinocular Microscope 21 mm 10X Eyepiece with 100/10 reticle Microforging Holding Pipettes A holding pipette with a large blunt tip and a small opening is used to hold a floating cell in place prior to microinjection by applying suction to the rear of the pipette. The procedure for making holding pipettes involves three steps: squaring off, large bore flame polishing, and tip reducing. These steps are accomplished with a larger heating filament. Microforging Beveled Injection Pipettes Occasionally, a beveled large bore pipette is not sharp enough to penetrate a cell without damaging the area around the pipette. With the DMF1000 and the large heating filament, a sharp point can be formed on the beveled tip to assist the penetration of the cell. This process is referred to as contact stretching. Pipette Tip Calibration & Microinjection The integrated digital pneumatic pressure system can be used to calibrate the precise diameter (I.D.) of a micropipette tip, based on a technique described previously (Hagag & Randolph 1990, Bowman & Ruknudin 1999). The pressure system can also be used separately as a simple but highly accurate controller for microinjection applications. AC POWER MODULE TIMER RANGE (for heater & timer) NUMBER OF MEMORYS PRESSURE ADJUSTING RANGE PRESSURE RESOLUTION FILAMENTS DMF1000 SPECIFICATIONS HEATER AND TIMER CONTROL DIMENSIONS: Control Unit SHIPPING WEIGHT MICROSCOPE SHIPPING WEIGHT 100-240 VAC 50/60 Hz 0.01 to 360 sec 10 0.5 – 60 PSI (3.5 – 414 kPa 0.1 PSI (0.7 kPa) H4 — Small filament for working with 40× long working distance objective. H5 — Large filament for working with 10× objective. Filament adjustment assembly provided for both objectives. Auto or Manual via Pushbutton, TTL, or Optional Foot switch. 4 × 7 × 17⁄8 in. (10.2 × 17.8 × 4.8 cm) 4 lb. (1.8 kg) W30S-LED (see below) 16 lb. (7.3 kg) W30S-LED SPECIFICATIONS HEAD Binocular (Seidentopf) Inclined 30°, rotates 360° Dual diopter adjustment, Interpupillary distance range 55-75mm 10X/18 wide field eyepieces Quadruple forward-facing nosepiece DIN Plan, anti-fungal 4X, 10X, 40X, 100XR (oil) Parfocal, parcentric, color-coded Mechanical stage (140mm x 140mm) Coaxial drive controls XY Movement: 73mm x 43mm Coarse adjustment: range of 30mm Fine adjustment: graduation of 2μm Tension control knob Moveable Abbe condenser, NA 1.25, Iris diaphragm Variable LED light source (3W bulb) 110V/220V switchable electronics BEVELERS NOSEPIECE DMF1000-1 Complete Microforge, incl W30S-LED Microscope (110 v) DMF1000-2 Complete Microforge, incl W30S-LED Microscope (220 v) DMF1000-M1 Microforge without microscope (110v) DMF1000-M2 Microforge without microscope (220v) *Above DMF1000 microforges include 40X long working distance objective OPTIONAL ACCESSORIES 500329 25x Long Working Distance Objective, 5 mm 0.50NA 500292 Optional 15x Eyepiece (pair) 13142 Optional foot switch REPLACEMENT ACCESSORIES 800292 40x Long Working Distance Objective, 3 mm 0.25NA 503513 21 mm 10X Eyepiece with 100/10 reticle DMF1000-H5 Replacement heating filament (large gauge) MF200-H4 Replacement heating filament (small gauge) 75050 Replacement Micropipette Slide 75040 Replacement Filament Cable UK: Tel: +44 (0)1462 424700 • wpiuk@wpi-europe.com OBJECTIVES STAGE FOCUS ILLUMINATION DIMENSIONS AND WEIGHT 15” (38cm) x 9” (23cm) x 7” (17.8cm) (h x l x w) 14 lbs. (6.4kg) World Precision Instruments www.wpiinc.com Germany: Tel: +49 (0)30-6188845 • wpide@wpi-europe.com US: Tel: 941-371-1003 • sales@wpiinc.com 119