1.Single cell determination of nitric oxide release using capillary electrophoresis with laser-induced fluorescence detection.
Yang Q1, Zhang X, Bao X, Lu H, Zhang W, Wu W, Miao H, Jiao B. J Chromatogr A. 2008 Aug 1;1201(1):120-7. doi: 10.1016/j.chroma.2008.06.001. Epub 2008 Jun 6.
Measurements of nitric oxide (NO) release at single cell level are fundamental to understand the diverse physiological functions of this remarkable molecule. To achieve this purpose, capillary electrophoresis with laser-induced fluorescence detection (CE-LIF) was originally described for the sensitive determination of NO release in individual neuron and mammalian cell after 8-(3,4-diaminophenyl)-2,6-bis(2-carboxyethyl)-4,4-difluoro-1,3,5,7-tetramethyl-4-bora-3a,4a-diaza-s-indacene (DAMBO-P(H)) was chosen as the fluorescent probe. Various parameters affecting NO trapping in vivo and CE separation were systematically studied. Under the optimal conditions, complete and fast separation of the resulted targeted high-fluorescent triazole (DAMBO-P(H)-T) was achieved in about 3 min (2.89 min), and the relative standard deviations (RSDs) values of migration time and peak area were less than 5% and 9% for intra-day and inter-day assays, respectively.
2.Determination of biogenic amines in apples and wine with 8-phenyl-(4-oxy-acetic acid N-hydroxysuccinimide ester)-4, 4-difluoro-1,3,5,7-tetramethyl-4-bora-3a,4a-diaza-s-indacene by high performance liquid chromatography.
Li JS1, Wang H, Huang KJ, Zhang HS. Anal Chim Acta. 2006 Aug 11;575(2):255-61. Epub 2006 Jun 3.
A precolumn-derivatization high performance liquid chromatographic method for biogenic amine analysis has been developed. Derivatization of biogenic amines was performed with a new fluorescent reagent, 8-phenyl-(4-oxy-acetic acid N-hydroxysuccinimide ester)-4,4-difluoro-1,3,5,7-tetramethyl-4-bora-3a,4a-diaza-s-indacene (TMPAB-OSu), which was synthesized in our lab. The derivatization conditions and the influence of elution composition on the separation were investigated. In pH 8.5 H3BO3-Na2B4O7 media, the reaction of biogenic amines with TMPAB-OSu completed at 45 degrees C for 5 min. The labeled biogenic amines were separated on an ZORBAX Eclipse XDB-C8 column (150 mm x 4.6 mm, 5 microm) and detected with fluorescence at excitation and emission wavelengths of 497 and 509 nm, respectively. Detection limits of biogenic amines were 0.1-4 nmol L(-1), at a signal-to-noise ratio of 3. The proposed method has been applied to the quantitative determination of spermine, phenethylamine, spermidine, cadaverine and putrescine in pericarp and pulp of mature and immature apples and wine with recoveries of 95-102% and R.
3.BODIPY-based azamacrocyclic ensemble for selective fluorescence detection and quantification of homocysteine in biological applications.
Li Z1, Geng ZR2, Zhang C1, Wang XB1, Wang ZL3. Biosens Bioelectron. 2015 Oct 15;72:1-9. doi: 10.1016/j.bios.2015.04.085. Epub 2015 Apr 28.
Considering the significant role of plasma homocysteine in physiological processes, two ensembles (F465-Cu(2+) and F508-Cu(2+)) were constructed based on a BODIPY (4,4-difluoro-1,3,5,7-tetramethyl-4-bora-3a,4a-diaza-s-indacene) scaffold conjugated with an azamacrocyclic (1,4,7-triazacyclononane and 1,4,7,10-tetraazacyclododecane) Cu(2+) complex. The results of this effort demonstrated that the F465-Cu(2+) ensemble could be employed to detect homocysteine in the presence of other biologically relevant species, including cysteine and glutathione, under physiological conditions with high selectivity and sensitivity in the turn-on fluorescence mode, while the F508-Cu(2+) ensemble showed no fluorescence responses toward biothiols. A possible mechanism for this homocysteine-specific specificity involving the formation of a homocysteine-induced six-membered ring sandwich structure was proposed and confirmed for the first time by time-dependent fluorescence spectra, ESI-MS and EPR.
4.8-Phenyl-(4-oxy-acetic acid N-hydroxysuccinimidyl ester)-4,4-difluoro-1,3,5,7-tetramethyl-4-bora-3a,4a-diaza-s-indacene as a new highly fluorescent-derivatizing reagent for aliphatic amines in disease-related samples with high-performance liquid chromatography.
Li JS1, Wang H, Cao LW, Zhang HS. Talanta. 2006 Jul 15;69(5):1190-9. doi: 10.1016/j.talanta.2005.12.035. Epub 2006 Jan 24.
A novel fluorescent-activated ester, 8-phenyl-(4-oxy-acetic acid N-hydroxysuccinimidyl ester)-4,4-difluoro-1,3,5,7-tetramethyl-4-bora-3a,4a-diaza-s-indacene (TMPAB-OSu) has been designed and synthesized for amine labeling in HPLC. Being used 11 aliphatic amines as the models, the derivatization conditions were optimized. In 0.2 mol/l borate buffer (pH 8.8), amines reacted with TMPAB-OSu at 30 degrees C to form the derivatives in 10 min. The fluorescent quantum yield of TMPAB-OSu and its amine derivatives are high even compared with fluorescein. The separation of these amine derivatives was achieved with a C(8) column and gradient elution by using 0.1 mol/l sodium acetate buffer (pH 5.0) and methanol. With fluorescence detection at an emission wavelength of 509 nm and an excitation wavelength of 497 nm, the detection limits of aliphatic amines were 2-18 fmol, at a signal-to-noise ratio of 3:1. The proposed TMPAB-OSu-based HPLC method has been applied to the analysis of urine samples of health, hepatic and renal patients and lake water.