Section 864.4400 - Enzyme preparations(a)Identification. Enzyme preparations are products that are used in the histopathology laboratory for the following purposes: (1) To disaggregate tissues and cells already in established cultures for preparation into subsequent cultures (e.g., trypsin);(2) To disaggregate fluid specimens for cytological examination (e.g., papain for gastric lavage or trypsin for sputum liquefaction);(3) To aid in the selective staining of tissue specimens (e.g., diastase for glycogen determination).(b)Classification. Class I (general controls). This device is exempt from the premarket notification procedures in subpart E of part 807 of this chapter subject to the limitations in § 864.9 .45 FR 60592, Sept. 12, 1980, as amended at 54 FR 25045, June 12, 1989; 66 FR 38789 , July 25, 2001