LC-MS/MS and FT-IR analyses of stones from a patient with Crohn’s disease: a case report

Studies on the formation of 5-aminosalicylate intercalated Zn–Al layered double hydroxides as a function of Zn/Al molar ratios and synthesis routes

“…The band at ca. 1243 cm −1 due to the amide III band (amide I and II bands were overlapped by the deformation mode of interlayer water and anti-symmetric stretching mode of COO − ) (Orioli et al, 2004) presents similar changes compared with that for 5-ASA (in Fig. 2 at 1255 cm −1 ), implying that amino group is also involved in hydrogen bond within the interlayer domain.…”

“…1492 and 1452 cm −1 due to the C&C stretching modes of aromatic ring in 5-ASA (Orioli et al, 2004) keep unchanged for EX products though less intensity of the latter band is observed. While for CP samples, these bands clearly red shift to 1486 and 1434 cm −1 upon intercalation and the latter become even broad and weak.…”

Development and validation of a HPLC-ESI-MS/MS method for the determination of 5-aminosalicylic acid and its major metabolite N-acetyl-5-aminosalicylic acid in human plasma

“…plasma [16,[18][19][20][21][22][23], serum [24], feces [24], urine [18,19,[22][23][24], stones [25] and rectal biopsies [23,24]. These methods include HPLC combined with UV [16,[25][26][27], fluorescence (FL) [14][15][16]18,20,28,29], and electrochemical (EC) [21] detections. The preanalytical step for human plasma analysis includes protein precipitation with acetonitrile [15], methanol [21,26,28,30] or perchloric acid [14,16,29].…”

“…Separation of 5-ASA and N-Ac-5-ASA derivative is usually performed by reversed-phase chromatography [16,18,28,29]. The direct analysis were carried out using ion pair methods [21,27] and, although affected by poor retention of 5-ASA, reversed-phase chromatography [20,25].…”

Determination of mesalamine by spectrofluorometry in human serum after solid-phase extraction with Ni-Al layered double hydroxide as a nanosorbent

“…1 A number of analytical methods has been developed for the analysis of mesalamine in pharmaceutical dosage forms and biological matrices. These methods include voltammetry, 2-4 spectrophotometry, 5,6 spectrofluorometry, 7,8 coulometery, 9 and high-performance liquid chromatography (HPLC) combined with UV, [10][11][12] fluorescence, 13,14 mass spectrometry (MS), 15, 16 and electrochemical (EC) 17 detections. Mesalamine is usually present at trace levels in a complex biological matrix, and the potentially interfering endogenous substances (which are usually present at higher concentrations than the drug) need to be removed before the analysis.…”