Batch and semicontinuous aggregation and sedimentation of hybridoma cells by acoustic resonance fields.

Ultrasound was used to enhance the sedimentation of hybridoma cells from medium in a 75 mL resonator chamber. Forces in the acoustic standing waves aggregated the cells, and the aggregates were then rapidly sedimented by gravity. Cell separation increased with acoustic treatment time and cell concentration.

Acoustic cell filter for high density perfusion culture of hybridoma cells.

We have developed a flow-through device which uses high frequency, low energy ultrasonic resonance fields to transiently aggregate hybridoma cells and return them by sedimentation to a perfusion bioreactor. The system retained up to 99 percent of the inflowing viable cells with no measurable effect on viability. Viable cells were selectively retained at up to 3 percent higher efficiency than nonviable cells.

A comparison of fructosamine and glycosylated haemoglobin measurements at a diabetic clinic.

Fructosamine or glycosylated haemoglobin (HbA1) measurements are most useful in the diabetic clinic if results are available when the patient is seen, with minimum waiting time. Fructosamine measurements have the advantage of being cheaper and faster to perform on large numbers of patients than HbA1 measurements. In order to assess the acceptability of fructosamine as a complete alternative to HbA1, fructosamine, HbA1 and random plasma glucose measurements were made on all patients attending the diabetic clinic for a 6-week period.