Detection of Biopolymer ϵ-poly-L-lysine with Molybdosilicate Anion for Screening of Synthetic Enzymes

Separation and Purification of ε-Poly-L-lysine from the Culture Broth Based on Precipitation with the Tetraphenylborate Anion

“…In a previous paper, 16 we reported that 12-molybdosilicate ([SiMo12O40] 4-) anion is useful as a precipitate reagent for the colorimetric detection of εPLH n+ cation. In this study, we found also that εPLH n+ is precipitated from aqueous media by the addition of sodium dicarbollylcobaltate 18 (NaDCC).…”

Analytical Methods for the Detection and Purification of ε-Poly-L-lysine for Studying Biopolymer Synthetases, and Bioelectroanalysis Methods for Its Functional Evaluation

“…However, since the precipitation reaction does not occur quantitatively, εPL could not be detected sensitively with anionic dyes, such as methyl orange and picrate. 8 It has been well known that cationic polymers, such as poly(diallyldimethylammonium chloride) and glycolchitosan, can be determined by colloidal titration with an anionic polymer. 20,21 However, the polycationic εPL did not form the colloidal particle with the anionic polymers, such as poly(vinyl sulfate).…”

“…On the basis of our finding, a colorimetric εPL microassay has been developed. 8 We also developed a method for the separation of εPL from a culture broth, which is based on precipitation of the polycationic εPL species with tetraphenylborate (TPB -) anion, and reprecipitation in the form of the hydrochloride salt. 9 Compared with the conventional column separation, the method is rapid and easy to carry out.…”

Separation and Purification of ε-Poly-l-lysine with Its Colorimetric Determination Using Dipicrylamine

“…When the DPA -anion was not in excess of εPL, the polycationic εPL may form a colloidal polyion complex. 12 When cPL < 0.8 mEq/L, the A420,20-value was proportional to cPL, and satisfies the prediction. The result indicates that εPL can be determined colorimetrically when the DPA -anion is added in excess.…”

“…Also, we have presented a colorimetric method for the determination of εPL based on a colored molybdosilicate anion. 12 Since εPL was precipitated selectively from culture broth, the molybdosilicate anion can be considered as a superior analytical reagent for εPL. However, it is not easy to isolate εPL from the precipitate with the molybdosilicate anion.…”