Steve Bruce’s side were handed a damaging defeat at St James’ Park by the Seagulls, but the club will not change their plans for the remainder of the transfer window because of it.
Newcastle want to bring in another centre-back and are likely to want to do so on a loan deal.
They also want another loan signing to be made, with a striker or an attacking player firmly in the Magpies’ sights.
Newcastle could also make a further permanent signing, however they have limited finances available to do a deal.
Bruce’s side are due to travel to Morecambe on Wednesday night in the EFL Cup, before they then head to the capital at the weekend to play Tottenham Hotspur in the Premier League.
Newcastle had new signings on display against Brighton, with Jamal Lewis slotting in at left-back, Jeff Hendrick starting, while Callum Wilson was up top.
Winger Ryan Fraser was brought on off the bench to replace Allan Saint-Maximin in the first half, after the Frenchman picked up an injury.