I have been using this method to clean my brushes, some cheap and others expensive, now for a while and I have not had any problems with hairs falling out or handles falling off. All the products I use to clean my brushes are normal household. Keeping your brushes clean can help minimise breakout and oily build up.
Before starting you need to combine 1 part extra virgin olive oil to four parts anti-bacterial washing up liquid in a bowl. It is really important to use a anti-bacterial washing up liquid as the whole purpose of cleaning brushes is to get rid bacteria, oil, grease and old make up which has built up during use. The extra virgin olive oil helps to lock in moister.
Rinse your brushes under warm water, make sure that you are holding the brush downwards to ensure that the water does not hit the glue as it could melt it and the hair will fall out.
Dip the brush into the solution then rub it firmly into the head using your palm. Keep the brush head down. Lots of foam should form, this breaks down the dirt on the hairs. Do this to all of the brushes leaving the solution on before moving on.
Now rinse the brushes under cold water (if hot water gets into the neck of the brush it could melt the glue holding the hairs in place). Pull the hairs downwards as you are doing this to make sure all of the foam is out. Keep doing this until there is no bubbles and the water runs clear.
Once all of the brushes are clean, you need to find a conditioner. If it is good enough for your hair it's good enough for make up brushes. Just work the conditioner through the hairs and keep it on for a while, just like you would do with you hair. At this stage you need to reshape your brushes as this helps the bristles to lay the way the would naturally.
Now rinse the conditioner off using cold water.
Finally I pop all of my wet brush on a hand towel and cover them with another towel and allow them to dry over night. Larger brushes may take longer though.
Hope you like it