Threads for tear film collection and support in quantitative amino acid analysis was written by Avilov, Vitaly;Zeng, Qi;Shippy, Scott A.. And the article was included in Analytical and Bioanalytical Chemistry in 2016.HPLC of Formula: 38183-12-9 This article mentions the following:
The collection of tears for chem. composition anal. is complicated by both the difficulty in sampling the tear film and the relatively low microliter volumes available for anal. The experiments in this study are focused on the demonstration of a method for determining amino acids from tear samples. Phenol red thread was used to absorptively collect tear fluid for qual. and quant. analyses of amino acids in basal, reflex, and emotional tears. The thread is also used as a support for sample preparation followed by elution with a buffer. The phenol red indicator on the thread turns from yellow to red with 15-s tear absorption and allows accurate volume measurement from 100 nL to over 1 μL. Derivatization of amino acids was performed directly on the thread with primary amine reactive fluorescamine for fluorescence detection. Analyte elution was performed via centrifugation with the thread in a pipet tip suspended in a centrifuge tube. Collected tear eluate was analyzed via capillary electrophoresis with LED-induced fluorescence. Glycine, glutamate, and aspartate were baseline resolved and used for method characterization. Recoveries were at 50 % for a single derivation and elution step but average recoveries near 90 % were found with two-step processing. Glutamate and aspartate are shown to be stable stored on thread for 3 days. Basal, reflex, and emotional tears were analyzed from three subjects showing distinct amino acid profiles for each tear type. The demonstration of this method may facilitate the development of routine tear compositional anal. to assess ocular health. [Figure not available: see fulltext.]. In the experiment, the researchers used many compounds, for example, 4-Phenyl-3H,3’H-spiro[furan-2,1′-isobenzofuran]-3,3′-dione (cas: 38183-12-9HPLC of Formula: 38183-12-9).
4-Phenyl-3H,3’H-spiro[furan-2,1′-isobenzofuran]-3,3′-dione (cas: 38183-12-9) belongs to benzofurans derivatives. Benzofurans are only weakly aromatic in nature and they are cleaved by many oxidative and reductive conditions. Substituted benzofurans find applications such as fluorescent sensors, oxidants, in drug discovery, and in another field of chemistry and agriculture.HPLC of Formula: 38183-12-9
Referemce:
Benzofuran – Wikipedia,
Benzofuran | C8H6O – PubChem