RT Journal Article SR Electronic T1 Monitor Lyophilization with Mass Spectrometer Gas Analysis JF PDA Journal of Pharmaceutical Science and Technology JO PDA J Pharm Sci Technol FD Parenteral Drug Association (PDA) SP 70 OP 75 VO 47 IS 2 A1 Connelly, John P. A1 Welch, John V. YR 1993 UL http://journal.pda.org/content/47/2/70.abstract AB This paper presents a brief review of the basic issues of lyophilization and the fundamentals of quadrupole mass spectrometry. The emphasis of the paper is on the application of a quadrupole mass spectrometer as a process monitor. The details of sampling and data collection are discussed. Data taken while monitoring lyophilization is presented in conjunction with cycle optimization, end point detection and contaminant detection.