A sensitive high-performance liquid chromatographic (HPLC) method using column switching is described for the determination of EM523 (I), a new erythromycin derivative, in human plasma and urine. The analyte was extracted from alkalinized plasma or urine with a mixture of n-hexane and acetone. After the evaporation of the organic layer, the reconstituted residue was injected into the HPLC system and separated on the first column. After column switching, the heart-cut fraction contamination the analyte was further separated on the second column and monitored by ultraviolet absorbance at 210 nm. The detection limits were 1 ng/ml in plasma and 10 ng/ml in urine. The method was applied to the clinical trials of I.

Download full-text PDF

Source
http://dx.doi.org/10.1016/0378-4347(93)80481-iDOI Listing

Publication Analysis

Top Keywords

plasma urine
12
column switching
12
sensitive high-performance
8
high-performance liquid
8
liquid chromatographic
8
determination em523
8
em523 erythromycin
8
erythromycin derivative
8
derivative human
8
human plasma
8

Similar Publications

Dual Ratiometric Fluorescence Sensors Based on Chiral Carbon Dots for the Sensitive and Specific Detection of Arginine.

Anal Chem

January 2025

State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, 5625 Renmin Street, Changchun 130022, P. R. China.

Arginine (Arg) is involved in tissue metabolism and regulates the immune function; thereby, achieving the detection of Arg is crucial for early diagnosis and treatment of diseases. Herein, dual ratiometric fluorescence sensors were prepared with the blue emission of levorotatory/dextrorotatory carbon dots (CDs) and the red emission of porphyrin (L/D-CDs-PP) for the sensitive and portable detection of Arg. Interestingly, L-CDs-PP and D-CDs-PP displayed not only the dual emission peaks at 493 and 650 nm but also different response modes to Arg; thus, they could serve as dual ratiometric fluorescence sensors to achieve the accurate and reliable detection of Arg, with the detection limit of 23.

View Article and Find Full Text PDF

Introduction: Complement 3 glomerulopathy (C3G) and primary immune complex membranoproliferative glomerulonephritis (IC-MPGN) have high risks for disease recurrence and allograft loss in transplant kidneys. Pegcetacoplan (targeted complement 3 [C3]/C3b inhibitor) may prevent excessive deposition of C3 and complement 5 [C5] breakdown products and associated renal damage.

Methods: NOBLE (NCT04572854) is a prospective, phase 2, multicenter, open-label, randomized controlled trial evaluating the efficacy and safety of pegcetacoplan in posttransplant patients with recurrent C3G or IC-MPGN.

View Article and Find Full Text PDF

This study evaluates the effects of liraglutide on albuminuria, oxidative stress, and inflammation in type 2 diabetes (T2D) patients with different urinary albumin-to-creatinine ratio (UACR) categories. We enrolled 107 patients with T2D who were initiating liraglutide for glycemic control. Patients were categorized into 3 groups: group I (UACR < 30 mg/g); group II (30 mg/g ≤ UACR ≤ 300 mg/g); group III (UACR > 300 mg/g).

View Article and Find Full Text PDF

Background: Focal segmental glomerulosclerosis (FSGS) and treatment-resistant minimal change disease (TR-MCD) are heterogeneous disorders with subgroups defined by distinct underlying mechanisms of glomerular and tubulointerstitial injury. A non-invasive urinary biomarker profile has been generated to identify patients with intra-kidney tumor necrosis factor (TNF)-activation and to predict response to anti-TNF treatment. We conducted this proof-of-concept, multi-center, open-label clinical trial to test the hypothesis that in patients with FSGS or TR-MCD and evidence of intra-renal TNF activation based on their biomarker profile, short-term treatment with adalimumab would reverse the elevated urinary excretion of MCP-1 and TIMP-1.

View Article and Find Full Text PDF

Prospective validation study of a combined urine and plasma test for predicting high-grade prostate cancer in biopsy naïve men.

Scand J Urol

January 2025

Department of Urology, Odense University Hospital, Odense, Denmark; Academy of Geriatric Cancer Research (AgeCare), Odense University Hospital, Odense, Denmark; Department of Clinical Research, University of Southern Denmark, Odense, Denmark.

Objective: Early and accurate diagnosis of prostate cancer (PC) is crucial for effective treatment. Diagnosing  clinically insignificant cancers can lead to overdiagnosis and overtreatment, highlighting the importance of accurately selecting patients for further evaluation based on improved risk prediction tools. Novel biomarkers offer promise for enhancing this diagnostic process.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!