Rapid Manual Paraffin Wax Processing
In the schedule below, it is presumed that the working day is from 8:00 a.m. to 5:00 p.m.. If other than that, appropriate adjustments should be made.
Tissue Preparation
- Thickness: No more than 3 mm thick.
- Area: 20 mm × 30 mm.
- Fixed tissue: Breadloaf large organs and store in NBF for 48 hours. Select tissue from fixed areas, trim to size and refix until the evening. If the trimmed sample is visibly unfixed, refix for a further 24 hours.
- Unfixed tissue: Slices of tissue should be thoroughly fixed before processing. Fix at least 24 hours after trimming to size.
- Times: All times in processing fluids for this schedule are for tissues 3 mm thick or less. Tissues thicker than that will require longer times.
- Clearing agent: Xylene or another clearing agent that will clear tissues in similar times should be used.
- Processing time: This schedule requires 2 days from the time the tissues go into the first ethanol. Weekends should be timed so that the tissue is in an ethanol or chloroform, rather than wax.
Processing Schedule
- Trim fixed tissues in the morning. Place into NBF until noon.
- 70% ethanol 2 hours.
- 95% ethanol until evening.
- First absolute ethanol overnight.
- Second absolute ethanol for 2 hours.
- Third absolute ethanol until noon.
- Fourth absolute ethanol for 2 hours.
- First clearing agent 1 hour.
- Second clearing agent 1 hour.
- Third clearing agent until evening.
- First wax at 58°C under vacuum overnight.
- Second wax at 58°C under vacuum 2 hours.
- Third wax at 58°C under vacuum until noon.
- Cast the blocks.
- Leave at room temperature overnight for the crystal structure to stabilize.
- Section.
Safety Note
Prior to handling any chemical, consult the Safety Data Sheet (SDS) for proper handling and safety precautions.
