Improved mass spectrometric detection of acidic peptides by variations in the functional group pKa values of reverse micelle extraction agents

Functional groups in reverse micelles maintain their aqueous phase pKa and allow selective extraction of peptides according to isoelectric point.

MATHEMATICAL MODELLING OF BACKWARD EXTRACTION MIXED REVERSE MICELLE OF AMOXICILLIN BY SURFACE RESPONSE METHODOLOGY (RSM)

One of important factor in reverse micelle extraction is backward transfer. It is important to investigate the favourable conditions for backward transfer from reverse micellar phase to an organic phase. The back extraction of amoxicillin was studied using mixed reverse micelle with combination sodium bis(2-ethylhexyl) sulfosuccinate (AOT) and TWEEN 85. Backward extraction was optimized via response surface methodology (RSM). For mathematical modelling, Central Composite Design (CCD) was used to studies the significant of independent variables: pH of stripping solution (5-8), KCl concentration (2.0 -16.0 g/L) and backward extraction time (5-35 minutes) on the response of the process. Optimized backward extraction for maximized final mass of amoxicillin extracted into aqueous were pH of stripping solution (6.58), backward time (19.8 minutes) and concentration of KCl (11.02 g/L) on the response of the process. Result showed that the experimental data was fitted well to a second-order polynomial model.

Reverse Micelle Liquid-Liquid Extraction of Bovine Serum Albumin and Lysozyme

Reverse micelle extraction by using Sodium bis (2-ethylhexyl) Suffoccinate (AOT) of protein bovine serum albumin (BSA) and lysozyme was investigated in this research. Study of factors affecting the surfactant concentration and pH of aqueous for both forward and backward extraction process was performed in the research. The BSA concentrations were characterized by using the UV- spectrophotometer at wavelength, λ = 280 nm. The result indicated that the extraction percentage of lysozyme was higher than BSA in forward transfer for both parameters; however BSA demonstrated a better extraction performance in backward extraction process. The maximum lysozyme extracted in the forward extraction process was at 60 mM of surfactant concentration while for BSA was 100 mM since BSA is a bulky molecule and the size is larger than of lysozyme. Pengekstrakan misel terbalik dengan menggunakan Sodium bis (2-ethylhexyl) Suffoccinate (AOT) untuk protein bovine serum albumin (BSA) dan lysozyme disiasat dalam penyelidikan ini. Kajian tentang faktor-faktor yang mempengaruhi kepekatan surfaktan dan pH akueus untuk proses pengekstrakan hadapan dan ke belakang telah dijalankan. Kepekatan BSA telah dicirikan dengan menggunakan spektrofotometer UV pada panjang gelombang, λ = 280 nm. Hasil kajian telah menunjukkan bahawa peratusan pengekstrakan lysozyme adalah lebih tinggi daripada BSA bagi pemindahan ke hadapan untuk kedua-dua parameter, namun begitu BSA menunjukkan prestasi pengekstrakan yang lebih baik di dalam proses pengekstrakan kebelakang. Jumlah maksimum lysozyme yang diekstrak di dalam proses pengekstrakan ke hadapan adalah 60 mM kepekatan surfaktan manakala bagi BSA adalah 100 mM disebabkan BSA adalah molekul yang sangat besar dan ia mempunyai saiz yang lebih besar berbanding daripada lysozyme.