hi edy, previously in my work place they use sharp plasmacluster. but not sure if they still make them.
just saw from a magazine about this Hunter air purifier using a 3M carbon pre-filter & a true HEPA filtration system. mayb you will like to chk out more details. it's emphasis on pet allergens.
Hunter Air Purifier by OLS Manufacturing Co.
i was also looking for a air purifier recently but end up buying a air humidifier. as my concern is the humidity in our air con bedroom which makes nikki skin kind of dry moreover it's much more affordable for us. but we did found out there are some health benefits (eg. lower risk of flu, cold & etc.) using a humidifier also.
but of course if we got to know of this hunter brand earlier we might have consider getting this coz we have dogs in our house, i guess 3M filter should be quite good moreover the price was like $300+ much cheaper than those purifier we saw in those electrical stores.