The Sensex opened with a negative gap of 30 points at 12,244, after slipping deeper into red the index bounced back into the positive zone to touch a high of 12,303.The index, however, could not hold gains and for long and slipped back into red. Sustained selling pressure in banking, FMCG and select technology stocks saw the index drop to a low of 12,170 - down 133 points from the day's high.Selective buying at lower levels saw the index recover some lost ground and finally finish with a loss of 37 points at 12,237.