Etching of silicon with mixtures of hydrofluoric acid and nitric acid is a widely used process in silicon solar cell fabrication. One precondition for an optimized usage of the acidic etching baths is the exact knowledge of the chemical bath composition. In this paper, we investigated a fast and online-capable method for the total analysis of all bath constituents by ion chromatography. The chromatographical system consists of a low-volume injection valve, which injects the concentrated samples directly into the KOH-based eluent. After separation and detection of nitrate and fluoride, a post-column derivatization with sodium molybdate is applied to detect the hexafluorosilicic acid, which enriches in the texturisation bath during the etching process. The results of the presented approach are discussed and compared with already published chromatographical and titration methods found in literature.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1016/j.talanta.2009.07.019 | DOI Listing |
Adv Pharmacol Pharm Sci
January 2025
Research Administrative Operations, Research and Innovation, King Faisal Specialist Hospital & Research Center, P.O. Box 3354, MBC-03, Riyadh 11211, Saudi Arabia.
A simple and efficient validated assay for quantifying 21-deoxycortisol (21-DOC), 17-hydroxyprogesterone (17-OHP), cortisol, and cortisone in human plasma has been developed using ultra-high performance liquid chromatography coupled with tandem mass spectrometry (UHPLC-MS/MS). Analysis of plasma samples were performed on Atlantis dC18 (3 m) column using a mobile phase of 20.0 mM ammonium acetate and acetonitrile (50:50, : ) that was delivered at isocratic flow rate 0.
View Article and Find Full Text PDFPhytochem Anal
January 2025
School of Pharmacy, Shenyang Pharmaceutical University, Shenyang, China.
Objective: This study aimed to qualitatively study the main chemical components of apple peel in APORT, Kazakhstan, by ultra-performance liquid chromatography-quadrupole-time-of-flight mass spectrometry (UPLC-Q-TOF-MS/MS) and to compare the components of apple peels with different provenances.
Methods: An ACQUITY UPLC HSS T3 (100 mm × 2.1 mm, 1.
J Chromatogr A
January 2025
Laboratório Bioquímica e Biofísica, Instituto Butantan, São Paulo, Av. Vital Brasil 1500, São Paulo, SP 05503-900, Brazil. Electronic address:
Although proteins in snake venoms have been extensively studied and characterized, low-mass molecules remain relatively unexplored, mainly due to their low abundance, secondary role in envenomation, and some analytical technique limitations. However, these small molecules can provide new important data related to venom toxins' molecular structure, functions, and evolutionary relationships. This research aimed to characterize molecules below 10 kDa in the venoms of snakes from the Viperidae families (Bothrops, Agkistrodon, and Bitis) and compare two chromatographic approaches: reverse-phase chromatography (RP), a classic technique, and hydrophilic interaction liquid chromatography (HILIC), an alternative technique, both coupled with high-resolution mass spectrometry (HRMS).
View Article and Find Full Text PDFSci Data
January 2025
Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.
As the occurrence of human diseases and conditions increase, questions continue to arise about their linkages to chemical exposure, especially for per-and polyfluoroalkyl substances (PFAS). Currently, many chemicals of concern have limited experimental information available for their use in analytical assessments. Here, we aim to increase this knowledge by providing the scientific community with multidimensional characteristics for 175 PFAS and their resulting 281 ion types.
View Article and Find Full Text PDFProtein Expr Purif
January 2025
Tohoku Medical and Pharmaceutical University, 4-4-1 Komatsushima, Aoba-ku, Sendai, Miyagi 981-8558, Japan. Electronic address:
Dectin-1 (CLEC7A), a C-type lectin-like receptor that recognizes β-1,3 glucans, has a key role in the innate immune system. While the lectin domain of mouse Dectin-1 has been solubilized and refolded from inclusion bodies in Escherichia coli, similar refolding of the human Dectin-1 lectin domain is hindered by the formation of misfolded multimers with aberrant intermolecular disulfide bonds. The aim of this study was to develop a method for the large-scale production of the human Dectin-1 lectin domain.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!