Improved quantification of protein in vaccines containing aluminum hydroxide by simple modification of the Lowry method.
Aluminum (Al) components in vaccines are known to act as adsorbents that interfere with accurate protein quantification by the Lowry method. Therefore, certain modifications based on the characteristics and compositions of the vaccine are required for determination of protein contents. We investigated the effects of an additional centrifugal separation and found that protein contents were overestimated by up to 238% without centrifugation through a collaborative study performed with hepatitis B vaccines containing Al. However, addition of a centrifugation step yielded protein concentrations that were similar to the actual values, with small coefficients of variation (CVs). Proficiency testing performed in 11 laboratories showed that four laboratories did not have satisfactory results for vaccines containing aluminum hydroxide, although all laboratories were proficient in protein analysis when samples did not contain aluminum hydroxide. Incomplete resuspension of aluminum hydroxide solution with alkaline copper solution was the major cause of insufficient proficiency in these laboratories.
Vaccines Division, National Institute of Food and Drug Safety Evaluation, 187 Osongsaengmyeoung 2-ro, Osong-eup, Heungdoek-gu, Cheongju-si 28159, Chungcheongbuk-do, Republic of Korea; Department of Life Science, University of Seoul, Siripdae-gil 13, Dongdaemun-gu, Seoul, Republic of Korea.
Naery
N
Lee
Vaccines Division, National Institute of Food and Drug Safety Evaluation, 187 Osongsaengmyeoung 2-ro, Osong-eup, Heungdoek-gu, Cheongju-si 28159, Chungcheongbuk-do, Republic of Korea.
SukJin
S
Shin
Vaccines Division, National Institute of Food and Drug Safety Evaluation, 187 Osongsaengmyeoung 2-ro, Osong-eup, Heungdoek-gu, Cheongju-si 28159, Chungcheongbuk-do, Republic of Korea.
Hye Joo
HJ
Chung
Vaccines Division, National Institute of Food and Drug Safety Evaluation, 187 Osongsaengmyeoung 2-ro, Osong-eup, Heungdoek-gu, Cheongju-si 28159, Chungcheongbuk-do, Republic of Korea.
Do Keun
DK
Kim
Vaccines Division, National Institute of Food and Drug Safety Evaluation, 187 Osongsaengmyeoung 2-ro, Osong-eup, Heungdoek-gu, Cheongju-si 28159, Chungcheongbuk-do, Republic of Korea.
Jong-Mi
JM
Lim
Department of Life Science, University of Seoul, Siripdae-gil 13, Dongdaemun-gu, Seoul, Republic of Korea.
Hyunsung
H
Park
Vaccines Division, National Institute of Food and Drug Safety Evaluation, 187 Osongsaengmyeoung 2-ro, Osong-eup, Heungdoek-gu, Cheongju-si 28159, Chungcheongbuk-do, Republic of Korea. Electronic address: ohojung@korea.kr.
Ho Jung
HJ
Oh
D000536:Aluminum Hydroxide; D002498:Centrifugation / Q000379:methods; D002623:Chemistry Techniques, Analytical; D017325:Hepatitis B Vaccines / Q000737:chemistry*; D011506:Proteins / Q000032:analysis*
D017325:Hepatitis B Vaccines; D011506:Proteins; D000536:Aluminum Hydroxide
Aluminum; Interference; Lowry method; National lot release; Protein quantification; Vaccine