On the Metachromasy of Polyvinylpyrrolidon (P.V.P.)

• Published in: Journal of the Spectroscopical Society of Japan Vol. 6; no. 3; pp. 10 - 14
• Main Authors: TSUBOMURA, Ichiro, YOSHIOKA, Junji, TORII, Kenzo
• Format: Journal Article
• Language: Japanese; English
• Published: The Spectroscopical Society of Japan 1957
• ISSN: 0038-7002; 1884-6785
• DOI: 10.5111/bunkou.6.3_10

1. Effects of P. V. P. addition upon pH range for color-changing and fluorescence of several dyes are examined. With Congo red (C. r.), color-changing point is shifted about 2 pH units. There are abserved some color change with benzopurplin 4B and its half-structure compound and the disapperance of fluorescence with eosin. 2. By means of two kinds of P. V. P. with different particular weights, absorption curves are drawn at PH 7.0 with and without P. V. P. In the presence of P. V. P., C. r. shows striking optical exaltation.Its half-structure compound (1/2C. r.) shows no absorption increase, but the shift of the wavelength at maximal absorption is observed. Methyl orange shows little difference whether P. V. P. coexists or not. 3. By means of eqilibrium dialysis technique, binding capacities of methyl orange and 1/2C. r. with P. V. P. and the competition between C. r. and 1/2C. r. towards P. V. P. are examined at pH 7.0 and 23°C. Compared with serum albumin, methyl orange shows less binding and 1/2C. r. more binding with P. V. P. Competition between C. r. and 1/2C. r. is verified. 4. Absorption measurement is carried out by varying P. V. P. concentration under constant dye concentration and at a given wave length. C. r. shows striking increase of absorption, followed by a saturation. 1/2C. r. and methyl orange show no increase. 5. It follows that the combination between C. r. and P. V. P. takes place through hydrogen bond between the terminal amino group of the former and the carbonyl group of the latter, and with methyl orange hydrogen bond can hardly be formed because of the presence of methyl group in dimethyl amino group.