The literature relating to the contamination of
ophthalmic ointments has been reviewed. The survival of
microorganisms deliberately incorporated into various eye
ointments has been studied, both qualitatively and
quantitatively, for organisms in pure and mixed culture.
The use of isopropyl myristate (IPM) as a dilutent for nonaqueous
products during the isolation (membrane filtration)
of contaminating organisms has been examined.
Both sterile filtered and autoclaved IPM were used.
aluminium containers (tubes) were compared on an in-use,
swept volume basis as part of contamination control, IPM did
not interfere with organism recovery and results suggest
that bacteria may survive for several days in such
ointments. Observations are discussed with respect to the
need for the inclusion of an added
preservative in ophthalmic ointments.
A Master's Thesis. Submitted in partial fulfilment of the requirements for the award of Master of Philosophy at Loughborough University.