Production of Lyophilized Microorganisms in Cosmetic Product for Proficiency Testing - การผลิตตัวอย่างทดสอบความชํานาญด้านเครืองสําอางโดยใช้จุลินทรีย์ในรูปผงแห้ง

Bureau of Cosmetics and Hazardous Substances, Department of Medical Sciences is appointed to be the ASEAN Cosmetic Reference Laboratory (ACRL) for Microbial Limit Test of cosmetic products. Proficiency testing (PT) is an important activity of ACRL but there is limited for finding the PT provider that fit for purposed. Thus, the bureau is necessary to develope the artificially contaminated cosmetic PT samples. Previously, we faced on the problems of stability of PT sample, only 3 days. This study aimed to get long stability by using the lyophilized microorganisms and sufficiently homogeneity and stability of target microorganisms which conform to the standard. The result found that all levels of target microorgan-isms in PT sample could be stable until 12 days at 2-8°C and the bulk material was sufficiently homoge-neity and stability to be the PT sample. Key words: proficiency testing sample, cosmetic, lyophilize