Rhodamine B Piperazinoacetohydrazine: A Water‐Soluble Spectroscopic Reagent for Pyruvic Acid Labeling

Abstract

A new water-soluble reagent, rhodamine B piperazinoacetohydrazine (RBPH), with improved spectroscopic and reaction properties, has been developed and characterized for pyruvic acid labeling. The reagent RBPH is designed and synthesized by using rhodamine B as a spectroscopic unit, and hydrazine as a carbonyl-specific labeling unit; the two units are connected by a well-chosen linker of piperazine, which prohibits the formation of the nonfluorescent spirocyclic structure of rhodamine B, thereby keeping the spectroscopic response of the reagent in a stable state. Such a design enables RBPH not only to maintain its excellent spectroscopic properties over a wide pH range, but also to exist as a stable cation with high water solubility. Moreover, the hydrazino group of RBPH is expected to react selectively with carbonyl compounds under mild conditions through the rapid formation of hydrazones. These important features make RBPH of great potential use in the labeling of aldehydes or ketones in various biosystems, and such an application of RBPH as a precolumn derivatizing reagent has been successfully demonstrated on the analysis of pyruvic acid in human serum by high-performance liquid chromatography with common UV/Vis detection.

Sensitive detection of ozone by a practical resorufin-based spectroscopic probe with extremely low background signal

“…As shown in Table 2, the analytical results of standard solutions from the two methods are in good agreement with each other using a Student's t -test30, clearly indicating the validity of our probe. Furthermore, the content of O 3 in the sample solutions (see Methods below for details) is not detectable by the iodometric titration due to its low sensitivity, but can be determined to be 0.21 μM with the present sensitive fluorescence method.…”

A water-soluble fluorescence resonance energy transfer probe for hypochlorous acid and its application to cell imaging

“…Acetonitrile and methanol (HPLC grade) were purchased from Thermo Fisher Scientific (Waltham, MA). RBPH was synthesized as reported previously [22]. Hypochlorous acid was prepared by distillation from the 5% commercial sodium hypochlorite solution.…”

“…A possible explanation for this phenomenon may be the fact that RBPH also has a relatively weak absorption band in the ultraviolet region (curve b in Figure 1), and can be excited at 370 nm. However, the acceptor RBPH has a higher fluorescence quantum yield ( = 0.19 in water) [22] than DNS-RBPH ( = 0.07 in water). Therefore, the reaction solution containing the released RBPH unit has the increased fluorescence …”

“…Recently, we developed a spectroscopic reagent, rhodamine B piperazinoacetohydrazine (RBPH, Scheme 1), for carbonyl labeling [22,23]. Because of its electrically charged character, RBPH has good water-solubility and can be used in pure aqueous media.…”

A new Cu2+-induced color reaction of a rhodamine derivative N-(3-carboxy)acryloyl rhodamine B hydrazide

“…In connection with a program of investigating new spectroscopic probes, a series of rhodamine probes have been developed in our laboratory [3,5,[24][25][26][27]. In the present study, we report the synthesis of a new rhodamine derivative, N-(3-carboxy)acryloyl rhodamine B hydrazide (CARB; Scheme 1), and its unusual spectroscopic reaction with Cu 2+ .…”