This comes two days after wheelchair-bound Madam Tay Quee Lang was found dead in her flat at Block 276 Tampines Street 22 with a knife reportedly lodged in her neck.
Minah, 37, is accused of causing the death of Madam Tay at about 2.10pm on Monday in the Tampines flat Madam Tay shared with her husband, who was not home at the time of the alleged killing.
Police said they received a call for assistance at about 2.10pm. When officers arrived at the unit on the fifth floor, they found the woman lying motionless. She was pronounced dead at the scene by paramedics.
In court on Wednesday, Minah, dressed in a black and white striped T-shirt, appeared calm as the capital charge was read to her by an interpreter.
She will be remanded for a psychiatric evaluation and will next appear in court on Mar 8.
If she is found guilty of murder, Minah will face the death penalty.