Section 17L. Deductions on payroll schedules may be made from the salary of a state, county, municipal or other public employee of an amount which such employee may specify in writing to any state, county or municipal officer or public department head, board, commission or agency by whom or which he is employed, for deposit into a ''qualified state tuition program'' as defined under the Internal Revenue Code and any prepaid tuition program established under general or special law if such purpose has been approved by the comptroller. An employee may withdraw such authorization for the deduction by giving at least 60 days notice in writing to the state, county or municipal officer or public department head, board, commission or agency by whom or which he is then employed. The state treasurer, the common paymaster as defined in section 133 of chapter 175, or the treasurer of the county, municipality or other public employer by which such employee is employed shall deduct from the salary of such employee such amount of authorized deductions as may be certified to him on the payroll and transmit the sum to the specified tuition program.