Solvent Green 7

• CAS: 6358-69-6
• Catalog Number: ACM6358696
• Category: Main Products
• Molecular Weight: 524.39
• Molecular Formula: C16H7Na3O10S3
• Synonyms: 1,3,6-Pyrenetrisulfonicacid,8-hydroxy-,trisodiumsalt
• Appearance: Yellow to green powder

Case Study

8-Hydroxy-1,3,6-pyrenetrisulfonic Acid Trisodium Salt (HPTS) as a Fluorescent Probe for Investigating Chitosan Interactions and Aggregation

Barnadas-Rodríguez, Ramon. Macromolecular Chemistry and Physics 214.1 (2013): 99-106.

8-Hydroxy-1,3,6-pyrenetrisulfonic acid trisodium salt (HPTS, pyranine) is a water-soluble fluorescent dye widely used to study vesicular systems and membrane permeability. However, its strong electrostatic interactions with cationic polymers like chitosan (CS) can complicate such studies. This work systematically investigates the interaction between HPTS and CS to elucidate the physicochemical basis of complex formation. HPTS bears three negatively charged sulfonate groups, while CS contains protonated free amino groups in acidic media.
Key Results:
· HPTS binding to CS shifts its ground-state equilibrium: at pH 3.3, the deprotonated species appears despite bulk acidity, indicating a higher local pH around CS. A bathochromic shift (3-6 nm) confirms a changed chromophore microenvironment.
· HPTS dramatically reduces CS solubility: increasing HPTS concentration lowers the critical precipitation pH (e.g., from ~6.5 to ~4.5 at 0.4 mM HPTS). NaCl at equivalent ionic strength causes no aggregation, indicating specific binding beyond charge screening.
· Zeta potential of CS decreases sigmoidally with HPTS, mirroring the association curve. The isoelectric point shifts from 7.6 (no HPTS) to 5.7 at 0.4 mM HPTS. NaCl causes only gradual, linear zeta potential reduction.
· Viscosity decreases similarly with HPTS and NaCl up to ~0.5 mM, but beyond this, HPTS induces massive aggregates-unlike NaCl, which progressively reduces viscosity without aggregation.
· Fluorescence microscopy confirms HPTS remains bound to precipitated CS aggregates even at alkaline pH, explaining partial resolubilization above pH 8 due to excess negative charge.

8-Hydroxy-1,3,6-pyrenetrisulfonic Acid Trisodium Salt (HPTS) as a Fluorescent Reporter for Surfactant Detection via Competitive Disassembly of Polyion Complexes

Liu, Shuai, et al. Polymers 10.6 (2018): 657.

This study introduces a fluorescent polyion complex formed between the cationic block copolymer poly(N-methyl-2-vinylpyridinium iodide)-b-poly(ethylene oxide) (PMVP41-b-PEO205) and the anionic fluorescent dye 8-hydroxy-1,3,6-pyrenetrisulfonic acid trisodium salt (HPTS) for the selective detection of the surfactant sodium dodecylbenzenesulfonate (SDBS).
Strategy: HPTS bears three sulfonate groups and exhibits strong fluorescence in aqueous solution. Upon complexation with PMVP41-b-PEO205 via electrostatic and aromatic interactions, HPTS fluorescence is efficiently quenched. Addition of anionic surfactants competitively displaces HPTS from the complex, restoring its fluorescence.
Key Results:
· Complex formation between HPTS and PMVP41-b-PEO205 was confirmed by UV-Vis and fluorescence spectroscopy: absorption at 403 nm decreased while a new band at 464 nm appeared; fluorescence at 512 nm was completely quenched at a 1:6 charge ratio (HPTS:PMVP).
· Among various surfactants (cationic, anionic, non-ionic, zwitterionic) and simple ions, only anionic surfactants (SDS, SDBS) induced fluorescence recovery. Remarkably, SDBS triggered significantly stronger recovery than SDS, enabling discrimination between anionic surfactants.
· The system showed high selectivity for SDBS due to additional π-π interactions between the benzene ring of SDBS and the pyridinium groups of PMVP, beyond mere electrostatic binding. Fluorescence recovery was linearly proportional to SDBS concentration (5-100 nM, R2 = 0.9903), with a detection limit as low as 0.1 nM. The system successfully detected SDBS in a model natural water matrix containing interfering surfactants and ions.

8-Hydroxy-1,3,6-pyrenetrisulfonic Acid Trisodium Salt (HPTS) as a Colorimetric and Fluorescent Sensor for Trace Water Detection in Organic Solvents

Bobe, Sharad R., et al. Australian Journal of Chemistry 67.4 (2014): 615-619.

Trace water detection in organic solvents is critical for many industrial and synthetic processes. 8-Hydroxy-1,3,6-pyrenetrisulfonic acid trisodium salt (HPTS), a commercially available fluorescent dye, was investigated as a dual-mode sensor for water in polar organic solvents (DMF, DMSO, ethanol, methanol).
Strategy: HPTS exhibits distinct optical responses upon water addition due to aggregation-induced changes in its microenvironment. UV-Vis absorption and fluorescence emission spectra were recorded in dry solvents and with increasing water content.
Key Results:
· Naked-eye color change: HPTS solutions appear blue in dry organic solvents but turn green upon addition of trace water (e.g., DMF + 9.09 × 10^-3 wt% water), enabling visual detection.
· UV-Vis spectra show decreased absorbance at 380 and 399-405 nm with increasing water content, accompanied by bathochromic shifts.
· Fluorescence emission decreases progressively with water addition; in DMSO, the 413 nm band diminishes while a new band appears at 512 nm, indicating significant microenvironmental changes.
· Detection limits are exceptionally low: 1.08 × 10^-4 wt% in DMF, 4.42 × 10^-4 wt% in DMSO, 3.35 × 10^-4 wt% in ethanol, and 4.40 × 10^-4 wt% in methanol-among the most sensitive reported for small-molecule water sensors.
· Quantification limits range from 3.62 × 10^-4 to 1.47 × 10^-3 wt%, with linear fluorescence response enabling accurate water content determination.

Custom Q&A

What is the molecular formula of Solvent Green 7?

The molecular formula of Solvent Green 7 is C16H7Na3O10S3.

What are the synonyms for Solvent Green 7?

The synonyms for Solvent Green 7 are 6358-69-6, Pyranine, HPTS, and Sodium 8-hydroxypyrene-1,3,6-trisulfonate.

What is the molecular weight of Solvent Green 7?

The molecular weight of Solvent Green 7 is 524.4 g/mol.

What is the parent compound of Solvent Green 7?

The parent compound of Solvent Green 7 is 8-Hydroxypyrene-1,3,6-trisulfonic acid.

What is the IUPAC name of Solvent Green 7?

The IUPAC name of Solvent Green 7 is trisodium;8-hydroxypyrene-1,3,6-trisulfonate.

What is the InChI of Solvent Green 7?

The InChI of Solvent Green 7 is InChI=1S/C16H10O10S3.3Na/c17-11-5-12(27(18,19)20)8-3-4-10-14(29(24,25)26)6-13(28(21,22)23)9-2-1-7(11)15(8)16(9)10;;;/h1-6,17H,(H,18,19,20)(H,21,22,23)(H,24,25,26);;;/q;3*+1/p-3.

What is the InChIKey of Solvent Green 7?

The InChIKey of Solvent Green 7 is KXXXUIKPSVVSAW-UHFFFAOYSA-K.

What is the canonical SMILES of Solvent Green 7?

The canonical SMILES of Solvent Green 7 is C1=CC2=C3C(=C(C=C2S(=O)(=O)[O-])S(=O)(=O)[O-])C=CC4=C(C=C(C1=C43)O)S(=O)(=O)[O-].[Na+].[Na+].[Na+].

What is the CAS number of Solvent Green 7?

The CAS number of Solvent Green 7 is 6358-69-6.

What is the hydroxyn bond donor count of Solvent Green 7?

The hydroxyn bond donor count of Solvent Green 7 is 1.