There is not a lot of information on Bruclens on the Internet, but it seems like it is packaged and sold by Wilkos in the UK, and its active ingredients include sodium percarbonate (the same active ingredient in OxyClean Free, which is a cleanser), and 7% chlorine (which is the sanitizer).
If I just made the sterilizer came in to contact with all of the bottle could I just leave it for 10 minutes before rinsing?
Yes. With chlorine-based sanitizers, as long as you mix them to the recommended concentration, you just have to keep the surface wet for the recommended contact time and do not need to completely immerse the item being sanitized. Then you must rinse off the sanitizer lest you end up with band-aid (plaster), chloraseptic (sort of like Dettol) off-flavors. Bruclens is not a no-rinse sanitizer, so you must rinse it off with sanitary water. I recommend keeping a spray bottle filled with your sanitizing solution, and you can spray things wet, including the inside of bottles.
Is putting the bottles in the oven as effective as using a sterilizer?
Yes, it can be, and here is how to do it. Some people on other forums have experienced that heating the bottles in the oven weakens the glass.
I also recommend switching in the future to a no-rinse sanitizer such as Star-San or Iodophor (sold in the UK as Betadine, Evans FamM30, Evans V.18 -- look for the words povidone-iodine or povidone). The same rule applies -- as long as you mix them to the recommended concentration, you just have to keep the surface wet for the recommended contact time -- and you do NOT have to rinse and SHOULD NOT rinse.