Boronic acid building blocks: tools for sensing and separation

Abstract

In this feature article the use of boronic acids to monitor, identify and isolate analytes within physiological, environmental and industrial scenarios is discussed. Boronic acids recognise diol motifs through boronic ester formation and interact with anions generating boronates, as such they have been exploited in sensing and separation protocols for diol appended molecules such as saccharides and anions alike. Therefore robust molecular sensors with the capacity to detect chosen molecules selectively and signal their presence continues to attract substantial attention, and boronic acids have been exploited with some success to monitor the presence of various analytes. Reversible boronic acid-diol interactions have also been exploited in boron affinity chromatography realising new separation domains through the same binding events. Boronic acid diol and anion interactions pertaining to sensing and separation are surveyed.

Molecular recognition with boronic acids—applications in chemical biology

“…This is the basis of a number of receptors for fluoride, cyanide and phosphate anions. The reactivity of boronic acids and their use as anion sensors have been covered recently in reviews by Nishiyabu et al [55], Wade et al [75] and Guo et al [26] (Fig. 2).…”

Functionalization of some benzylthioarylboronic acids by benzylic lithiation of their N‐butyldiethanolamine esters or lithium (triisopropoxy)borates

“…The obtained borio-lithio derivatives can be easily converted into various functionalized arylboronic acids that can be used in coupling reactions [10,11] or tested as saccharides sensors. [12,13] …”

Hyperbranched–hyperbranched polymeric nanoassembly to mediate controllable co-delivery of siRNA and drug for synergistic tumor therapy

“…Therein, the inner core of HBPO aggregates was responsible for the accommodation of antitumor drugs through hydrophobic interaction while the surface clustering of cationic OEI600-PBA units allows much enhanced affinity to siRNA over parent OEI600-PBA. Of special note, owing to the acidity-labile feature of phenylboronate linkage, [18][19][20] HBPO/OEI600-PBA nanoassembly is expected to undergo reversible disintegration upon the cellular endocytosis into the lysosome compartment featured with considerably low pH 4.0~5.5. This transition would facilitate the liberation inside tumor cells of the extracellularly protected siRNA/drug payloads, favoring the synchronization of two therapeutic mechanisms.…”