CE‐ESI‐TOF/MS for human growth hormone analysis

Abstract

CE is a powerful analytical tool used to separate intact biomolecules such as proteins. The coupling of CE with TOF/MS produces a very promising method that can be used to detect and identify proteins in different matrices. This paper describes an efficient, rapid, and simple CE-ESI-TOF/MS procedure for the analysis of endogenous human growth hormone and recombinant human growth hormone without sample preparation. Operational factors were optimized using an experimental design, and the method was successfully applied to distinguish human growth hormone and recombinant human growth hormone in unknown samples.

Development and validation of a liquid chromatography–mass spectrometry procedure after solid-phase extraction for detection of 19 doping peptides in human urine

“…Finally, novel, previously unknown macromolecules (i.e., TB500 17-23 fragment), with no current approval for human therapeutic use (i.e., agents under preclinical or clinical development, designer drugs, or compounds approved only for veterinary use), but illegally marketed (e.g., via Internet websites) [5] are included in section S0 ''Non-approved substances''. Different analytical approaches have already been developed and published to detect these compounds in nutritional supplements [6][7][8][9][10] and in doping control samples (either blood [11][12][13][14][15][16][17][18] or urine [19][20][21][22][23][24][25][26][27][28][29][30][31][32][33][34][35][36][37]), employing immunological [26,[35][36][37], electrophoretic [16][17][18][19]27], or liquid chromatography-mass spectrometry techniques [6-15, 20-25, 28-34] or a combination of different analytical technologies. In general, the most effective analytical approach (combined sample pretreatment and the instrumental method) has to take into ...…”

Use of organic solvent to prevent protein adsorption in CE‐MS experiments

“…The best results in terms of sensitivity (with the signal-to-noise ratio) and efficiency were obtained at basic pH without ACN for Hb, at basic pH with 10% ACN for INS, and at acidic pH with 20% ACN for GH. MS parameters were adapted from the results obtained from the experimental design carried out in a previous study [29]: the ESI capillary voltage was set at 14500 V, the nebulizing gas pressure at 4 psi, the drying gas flow rate at 4 L/min À1 , and the drying gas temperature at 1501C. The sheath liquid was composed of isopropanol-water-formic acid in all cases, but in different proportions and delivered at different flow rates.…”

“…For this reason, fewer applications were performed at this pH in comparison with alkaline conditions. However, as the acidic pH could permit different selectivity, its use should be considered for the intact protein analysis [29]. Experiments were first conducted without ACN.…”

New Insights in Pharmaceutical Analysis

“…[17] An efficient, rapid, and simple CE-ESI-TOF/MS procedure was developed for the analysis of endogenous human growth hormone (hGH) and recombinant human growth hormone (rhGH), in collaboration with the LAD. [11] Attention was focused on optimizing CE and ESI conditions to enhance selectivity, efficiency, and sensitivity while hindering protein adsorption onto the capillary walls. [18] To optimize CE-ESI-MS interfacing, a chemometric approach was implemented to evaluate the most relevant factors and determine the optimal conditions.…”

“…ESI is thus well suited for the analysis of ionizable or polar compounds, ideally separated by capillary zone electrophoresis, such as small pharmaceutical molecules and intact proteins. [11][12][13] Atmospheric pressure photoionization (APPI) was introduced as a technique complementary to ESI to broaden the range of ionizable analytes. The coupling of APPI to CE-MS was investigated in our group because of its low ion suppression and to evaluate its sensitivity at the very low flow rates of CE separations.…”