CID(Operations) Jayaraman led the team, which also spoke to the widow Shalini Saha, official sources here said.
The forensic team from Kolkata collected samples from the house, the sources said.
The doctor Bikram Saha had committed suicide suicide by taking an overdose of insulin injection on June 9 and had died in a private hospital in Kolkata on June 13, the FIR said.
The widow had complained that he was being tormented by CPI-M state committee member Dipak Sarkar and six doctors of Midnapore Medical College and Hospital who were forcing him to work in a paramedical centre run by a charitable organisation.
This had caused mental depression in Saha, an assitant professor of Midnapore Medical College and Hospital, and he was declared a psychiatric patient by a board of doctors in the hospital.
The charitable organisation is headed by Sarkar, who has, however, said he did not know the doctor.
Hospital sources said he had not attended the hospital for the past three years due to his illness.