Hi Mustang ,
That is true, we have to know more about these hollow
PMMA beads ( micro- balloons) btw these are made for a longer priod ( for drug delivery, in cosmetic etc. ).
There was always the idea to find a strong carrier which has a density almost near to the
PMMA density i.e. 1.2 g/cm3 ( actually it is exactly 1.19g/cm3) but the problem with that type of carrier will be very viscose and will be very difficult even impossible to be injected through a needle, Lemperle mentioned before you need a strong carrier for the
PMMA beads just to distrbute them evenly and thats why he said the carrier in the brazillian products Cellulose is a weak carrier and cannot carry the beads i.e. precipitation will definitely occur ----> nodules or even lumps.
So we have either of 2 choices :- one to increase the density of the carrier which was explained why it wil be difficult or to reduce the dendity of the
PMMA beads by forming different sizes of micro- balloons
PMMA i.e. different volumes of voids which depends on the chosened carrier ( i.e. its density) .
I think with this Patent the inventor did solve a major problem in regard how to make these
PMMA beads floating within the carrier without a chance of precipitation.
The best way is to examine these micro- balloons mixed with a filler with the same density in vitro and in vivo ( after few monthd) under SEM.
It will be great if we could contact this inventor ..
I had a reply from Lemperle :-
this is certainly a good idea for indications copied from our \"Lemperle-Patent\" . The problem again is the FDA, who has once approved solid microspheres (from
PMMA and Ca) - and all new inventions have to prove their safety and effectivity through new clinical trials... (which may cost $ 5-10 million).
That non-flexible behavior of the FDA inhibits progress tremendously. Best, Gottfried