| 초록 |
Paracetamol (acetaminophen) is an analgesic drug that is used worldwide in the manufacture of many millions of tablets and other dosage forms every year. The crystal structures for two known crystal modifications of paracetamol (monoclinic and orthorhombic) have already been published. Monoclinic paracetamol is the thermodynamically stable modification at room temperature with respect to the orthorhombic modification. Monoclinic paracetamol (formⅠ), which is the commercially used form, is not suitable for direct compression into tablets. In this study, by adjusting the degree of supersaturation, crystallization mode (cooling) and operating crystallization conditions(cooling rate, agitation speed, initial concentration): needed polymorphs of paracetamol were selectively crystallized. While 60℃ paracetamol’s saturation solution is cooled to 10℃, double jacket is mesured by in-line Raman spectroscopy. Increasing the cooling rate, and decreasing the agitation speed, metastable formⅡis easily obtained. When the initial concentration is high or low, irregular movements showed (formⅠand formⅡall get). |
