Bertani was born at Milan on October 19, 1812. He took part in the revolutions of 1848, but he was opposed to the fusion of Lombardy with the Kingdom of Sardinia. During existence of the Roman Republic of 1849, he, as medical officer, organized the ambulance service. After the fall of Rome, he withdrew to Genoa, where he worked with James Hudson, a British diplomat and supporter of Italian independence, for the freedom of Neapolitan political prisoners.  In 1859 he founded a revolutionary journal at Genoa.
At the outbreak of the Second Italian War of Independence in 1859, he joined as surgeon the Garibaldian corps. After the war ended with the Conference of Villafranca, he became the organizer-in-chief of the Expedition of the Thousand against the Kingdom of the Two Sicilies. Remaining at Genoa after Garibaldi's departure for Marsala, he organized four separate volunteer corps, two of which were intended for Sicily and two for the Papal States. The Sardinian Prime Minister, Camillo Cavour, however, commanded all four corps to sail for Sicily.
When Garibaldi took Naples, Bertani was appointed Garibaldi's secretary-general, in which capacity he reorganized the police, abolished the secret service fund, founded twelve infant asylums, prepared for the suppression of the religious orders, and planned the sanitary reconstruction of the city. He entered parliament in 1861 and opposed the Garibaldi's expedition against Rome. After Garibaldi was defeated at the Battle of Aspromonte in 1862, he treated Garibaldi's wounds. In 1866, during the Second Italian War of Independence, he organized the medical service for the 40,000 Garibaldians, and the following year fought at the Battle of Mentana.
Life in parliament
In 1866, Bertani founded a journal for social reform called La Riforma.
Bertani's parliamentary career was less successful than his revolutionary activity. After the capture of Rome in 1870 he became the leader of the extreme left in the new Italian parliament. His chief work as deputy was an inquiry into the sanitary conditions of the peasantry, and the preparation of the sanitary code adopted by the administration of Francesco Crispi. With the introduction of "transformismo" by Agostino Depretis in 1876, drawing ministers from the right and left, Bertani refused to enter the government.  In 1885, along with Anna Maria Mozzoni, he made a visit to the anarchist Giovanni Passannante, imprisoned for attempted murder to King Umberto I, and denounced his prison conditions.
Bertani remained in parliament until his death on April 10, 1886.