Yes, there is an airport express bus carrying passengers directly from the Baku airport to 28 May Metro Station. The bus stops at Koroglu metro before reaching 28 May metro station. You can board these buses from the terminal opposite the official airport taxi rank. To buy a ticket, go to BakuCard Kiosk, select a card and add some credit to it. You cannot buy tickets on the bus. You require some Manats (Azeri currency) because the machine does not accept card payments. These buses are equipped with wifi, air conditioning, and toilets.