Thymolphthalein

Abstract: In this work, an innovative enzyme-free colorimetric immunoassay was proposed for the sensitive detection of alpha-fetoprotein (AFP) by introducing thymolphthalein-modified metal-polydopamine framework (MPDA@TP) for the signal generation and amplification. Using zeolitic imidazolate framework (ZIF-67) as the template, the hollow-structured metal-polydopamine framework (MPDA) with high surface recovery and abundant groups was synthesized and functionalized with thymolphthalein (TP) molecules via typical π-stacking reaction. In the presence of target AFP, an MPDA@TP-linked immunosorbent assay (MLISA) was implemented on the capture antibody-modified microplate by using detection antibody-labeled MPDA@TP as the secondary antibody. Upon alkaline solution introduction, the coated hydrophobic TP on the MPDA was deprotonated into hydrophilic TP2– ion and dissolved in the solution, thereby resulting in the color change of the solution from nearly colorless to deep blue, and the increasing absorbance of the solutio...

Abstract: We describe the use of sodium thymolphthalein monophosphate as a substrate for measuring acid phosphatase activity in serum. Thymolphthalein is liberated in the reaction and is conveniently measured by increasing the pH of the medium, which produces a color and also stops the hydrolysis. Optimal conditions for enzymatic activity were defined for use in the final assay system. Purified acid phosphatase isoenzymes from various human tissues and sera from patients with nonprostatic diseases most likely to affect serum acid phosphatase activity were used to show that the new method is more specific for the prostatic enzyme than other commonly used procedures for acid phosphatase. Other advantages include simplicity, good sensitivity over a wide range of activity, high precision, zero-order kinetics to about 200 times the upper limit of normal, easy standardization by a pure standard, and reagent stability.

Abstract: PURPOSE:To ensure high sensitivity, high resolution, superior heat resistance, dimensional controllability and pattern shape by specifying poly (p- hydroxystyrene), a dissolution inhibitor, an onium salt, a nonionic surfactant, an acid deactivator and an org. solvent. CONSTITUTION:This resist compsn. contains poly(p-hydroxystyrene), a dissolution inhibitor, an onium salt, a nonionic surfactant, an acid deactivator and an org. solvent. The poly(p-hydroxystyrene) is synthesized by anionic polymn. and the wt. average mol. wt. is 8,000-20,000. The dissolution inhibitor is bis (p-t- butoxycarbonylmethyl)thymolphthalein represented by the formula. The onium salt is bis (p-t-butylphenyl)iodonium triflate. The acid deactivator is a compd. having one amino group and one carboxyl group in one molecule. The org. solvent is propylene glycol monomethyl ether acetate.

Abstract: The aqueous coating composition, which is particularly adaptable for use as a household floor polish or a temporary protective coating for various articles, contains a non-volatile, solid film former, such as an acrylic copolymer, dispersed in the aqueous phase or base, and a water-soluble, acid-base indicator, such as thymolphthalein, which is colored at a pH above a predetermined level and is colorless at a lower pH. Upon being applied on the surface of a substrate, a substantially colorless film is formed thereon upon the evaporation of the water and the color indicator becomes an integral part of the dried film. Upon the application of an aqueous alkaline cleaning or stripping solution having a pH above that required to effect a color change of the color indicator, (e.g., above about 11.6 when thymolphthalein is used), the film changes to a distinctive color (e.g., blue when thymolphthalein is used) so that one can readily observe whether the old film has been completely removed before the surface becomes dry. The film former can include optional ingredients, such as a wax, an alkali-soluble resin and a permanent plasticizer to improve the wear resistance and finish properties of the resultant film. The coating composition can also include fugitive plasticizers or coalescing aids to facilitate the formation of a smooth, continuous protective film.