C.B.S. Scientific SG Series - Manual (Page 23)

C.B.S. œ Scientific
23
Adjustable Height Sequencer
5.2 Troubleshooting Guide
Problem/Condition Cause & Solution
ELECTRICAL
• 'No Load' power supply indicator
(no current)
• loose connection at DC source or at terminal: secure if not broken
• press down firmly on both safety cover lids
• loose electrode terminal: finger tighten, check for corrosion: clean
thoroughly
• break in platinum wire: check for continuos wire
• if sides of plate sandwich not taped - may be grounding; check for
leaks/streaking- wipe clean, check number and type of clamps; ensure
equal number and symmetrical spacing
• incorrect buffer levels
• gel hydrolyzed: recheck gel components;
re-pour
• 'sparking' near top of gel • check upper buffer level and refill
• 'sparking' near lower gel chamber • check lower buffer level: too low or too high
• Over heating of buffer and plates • buffer: check concentration & date made
• hydrolyzed gel: date of gel stock solution; remake
• set power conditions to run gel at approximately 50°C
• Upper well & gasket area • not flush & tight against silicone seal: check clamps and bar clamp (if
used)
GLASS PLATES
• cracking at notched area
• check clamps for correct size, Cat.# GPC-0001
• optional bar clamp: too tight and uneven
• cracking across main area • overheating (see ELECTRICAL section above)
• use aluminum heat dispersion plate (cooling)
• check clamps: check for proper size; avoid using metal bulldog-type
clamps
• check for pre-existing scratches or chips along edges
LEAKS
• upper buffer reservoir and sample wells/gasket area
• ensure notched or shorter plate tightly flushed against silicone gasket;
check for proper plate alignment
• thoroughly clean silicone gasket area
• replace gasket if worn, cracked or flattened
• check tightness & clamp type
• capillary leakage • sides of gel plate sandwich (see 'no load' section above)
• ensure that an equal number of white spring clamps are symmetrically
placed on both sides of plates
• check clamp model number (GPC-0001 vs. GPC-0002)
• ensure stainless steel spring in clamp securely in place
• space and sequencing comb identical thickness
• bowed (not flat) plate set
• Polymerization problem (see following section)
• gel casting • ensure spacers meticulously clean
• sloppy technique if using tape
• check excess gel solution (if saved) for proper polymerization time
DEFORMED SAMPLE WELLS
• deformation when comb removed
• comb inserted too far
• gel dried out near surface: rinse comb with buffer before removal of
comb
• gel not polymerized
BUBBLES
• plates not cleaned thoroughly prior to casting
SEPARATION OF PLATES AFTER
ELECTROPHORESIS
• sticking of gel to one or both plates
• plates not cleaned thoroughly
• plate (1) not silanized (recommend 'GEL COAT'
• plate pried apart too quickly: separate slowly and carefully; use Wedge
plate separator, Cat. # WPS-100
READ FRAMES
• fuzzy/wavy
• before loading samples, flush urea out of sample wells using pipette
tip or syringe with bent needle
• smeary • re-pour gel using freshly purified gel components
SMILING
• use an aluminum heat dispersion plate
• avoid loading samples in the two outermost wells on both sides
• reduce power setting