For Publishers
DiscoveryMetadataPeer reviewHostingPublishing
For Researchers
JoinPublishReviewCollect
Register
Blog
About
Search
Advanced search
My ScienceOpen
Search
For Publishers
For Researchers
Blog
About
23
views
46
references
 Top references
cited by
3
    
0 reviews
 Review
0
comments
 Comment
0
recommends
+1 Recommend
0 collections
    0
    shares
      115
      similar
       All similar
      • Record: found
      • Abstract: found
      • Article: found
      Is Open Access

      Spectrophotometric Determination of N-Acetyl-L-Cysteine and N-(2-Mercaptopropionyl)-Glycine in Pharmaceutical Preparations

      research-article

      Read this article at

      ScienceOpenPublisherPMC
      Bookmark
          There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.

          Abstract

          A simple spectrophotometric method for the determination of N-acetyl-L-cysteine (NAC) and N-(2-mercaptopropionyl)glycine (MPG) in pharmaceutical preparations was developed, validated, and used. The proposed equilibrium method is based on a coupled two-step redox and complexation reaction. In the first step, Fe(III) is reduced to Fe(II) by NAC or MPG. Subsequently, Fe(II) is complexed with 2,4,6-tripyridyl-s-triazine (TPTZ). Several analytical parameters of the method were optimized for NAC and MPG analysis in the concentration range from 1.0  μM to 100.0  μM. Regression analysis of the calibration data showed a good correlation coefficient (0.9999). The detection limit of the method was 0.14  μM for NAC and 0.13  μM for MPG. The method was successfully applied to quantify NAC and MPG in pharmaceutical preparations. No interferences were observed from common pharmaceutical excipients.

          Related collections

          Most cited references46

          • Record: found
          • Abstract: found
          • Article: not found

          Medical treatment of cystinuria: critical reappraisal of long-term results.

          F. Barbey, D. Joly, P Rieu … (2000)
          We evaluated long-term results of a contemporary medical therapeutic regimen in patients with cystinuria and analyzed factors predictive of therapeutic success. A total of 27 adults with cystine urolithiasis were treated at our institution for 1.3 to 32 years (mean 11.6, overall 312 patient-years). We obtained data on the pre-referral period for 274 patient-years overall. Basic therapy included hyperdiuresis and alkalization. The thiols D-penicillamine or tiopronin were added when standard therapy failed to prevent new stones and stone growth or dissolve preexisting stones. X-ray and echography were performed every 4 months during the initial 2 years and every 6 months thereafter. In the pre-referral period 256 stone episodes occurred and 81 urological procedures were performed in 24 patients (0.93 and 0. 29 per patient-year, respectively). Nine patients were treated with added thiols. During the therapeutic period the incidence of stone episodes decreased to 66 (0.20 per patient-year, p <0.001), while the need for urological procedures decreased to 44 (0.14 per patient-year, p <0.001). No further urological procedures were required in 15 patients, including 4 treated with thiols. However, the remaining 12 patients, including 5 treated with thiols, underwent 1 to 7 procedures each (mean 0.26 per patient-year). In the 2 groups mean daily cystine excretion plus or minus standard deviation at baseline (863 +/- 253 versus 761 +/- 270 mg. daily) and mean urinary pH of about 7.4 did not differ significantly. However, daily urine volume was significantly higher in patients with arrested stone formation (3,151 +/- 587 versus 2,446 +/- 654 ml./24 hours, p = 0.006). Our study provides evidence that a regularly followed medical program based on high diuresis and alkalization with second line addition of thiols may arrest or markedly decrease cystine stone formation and preclude the need for urological procedures in more than half of the patients. However, patients poorly compliant with hyperdiuresis remain at risk for recurrence. We suggest that maintaining a daily urine volume of greater than 3 l. is essential for therapeutic success regardless of whether thiol derivatives are administered.
          Article 0 comments Cited 25 times – based on 0 reviews     Review now
            Bookmark
            • Record: found
            • Abstract: not found
            • Article: not found

            2,4,6-Tripyridyl-s-triazine as Reagent for Iron. Determination of Iron in Limestone, Silicates, and Refractories

            Harvey. Diehl, G. F. Smith, P Collins (1959)
            Article 0 comments Cited 14 times – based on 0 reviews     Review now
              Bookmark
              • Record: found
              • Abstract: found
              • Article: not found

              Analysis of cysteine and N-acetylcysteine in human plasma by high-performance liquid chromatography at the basal state and after oral administration of N-acetylcysteine.

              J Sandmann, J Fauler, Andreas Frölich … (1998)
              A high-performance liquid chromatographic method for the determination of free reduced cysteine and N-acetylcysteine in human plasma at the basal state and after oral administration of N-acetylcysteine is described. The method is based on acid-catalysed conversion of plasma thiols to the corresponding S-nitroso derivatives by excess of nitrite and their subsequent cation-pairing RP-HPLC with detection at 333 nm. Recovery rates of cysteine and N-acetylcysteine added to human plasma were 94.6 and 99.6%, respectively. Inter- and intra-day precision were below 6%. In healthy humans (n = 5), free reduced cysteine was determined to be (mean+/-S.E.) 10.0+/-0.96 microM. No N-acetylcysteine was detected in plasma of these subjects above the limit of detection (e.g. 170 nM). The method was successfully applied to a pharmacokinetic study on orally administered N-acetylcysteine to healthy volunteers.
              Article 0 comments Cited 10 times – based on 0 reviews     Review now
                Bookmark
                All references

                Author and article information

                Journal
                Journal ID (nlm-ta): Int J Anal Chem
                Journal ID (publisher-id): IJAC
                Title: International Journal of Analytical Chemistry
                Publisher: Hindawi Publishing Corporation
                ISSN (Print): 1687-8760
                ISSN (Electronic): 1687-8779
                Publication date (Print): 2011
                Publication date (Electronic): 23 May 2011
                Volume: 2011
                Electronic Location Identifier: 140756
                Affiliations
                Department of Analytical Chemistry, Faculty of Chemistry and Technology, University of Split, Teslina 10/V, 21000 Split, Croatia
                Author notes
                *Lea Kukoc-Modun: lkmodun@ 123456gmail.com

                Academic Editor: D. Tsikas

                Article
                DOI: 10.1155/2011/140756
                PMC ID: 3103845
                PubMed ID: 21647283
                SO-VID: 1a6adf83-7923-4de4-bbe9-28f35fb10fac
                Copyright © Copyright © 2011 L. Kukoc-Modun and N. Radić.
                License:

                This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

                History
                Date received : 13 January 2011
                Date revision received : 2 March 2011
                Date accepted : 12 March 2011
                Categories
                Subject: Research Article

                ScienceOpen disciplines: Analytical chemistry
                Data availability:
                ScienceOpen disciplines: Analytical chemistry

                Comments

                Comment on this article

                scite_

                Similar content115

                See all similar

                Cited by3

                See all cited by

                Most referenced authors296

                See all reference authors