Surface-Enhanced Raman Spectroscopy (SERS) for Identifying Traces of Adenine in Organic-Bearing Extraterrestrial Dust Analogs Captured in the Tanpopo Aerogel after Hypervelocity Impacts.

Raman spectroscopy is a non-destructive analytical technique for characterizing organic and inorganic materials with spatial resolution in the micrometer range. This makes it a method of choice for space-mission sample characterization, whether on return or in situ. To enhance its sensitivity, we use signal amplification via interaction with plasmonic silver-based colloids, which corresponds to surface-enhanced Raman scattering (SERS).

Upcycling Polyolefin Blends into High-Performance Materials by Exploiting Azidotriazine Chemistry Using Reactive Extrusion.

The revalorization of incompatible polymer blends is a key obstacle in realizing a circular economy in the plastics industry. Polyolefin waste is particularly challenging because it is difficult to sort into its constituent components. Untreated blends of polyethylene and polypropylene typically exhibit poor mechanical properties that are suitable only for low-value applications.

On-site contactless surface analysis of modern paintings from Galleria Nazionale (Rome) by reflectance FTIR and Raman spectroscopies.

Seven artworks representing the diversity of paints used around the 1960s and created by German and Italian painters (J. Albers, A. Bonalumi, L.

Self-assembly/condensation interplay in nano-to-microfibrillar silicified fibrin hydrogels.

Fibrin-based gels are used in clinics as biological glues but their application as 3D cellularized scaffolds is hindered by processing and stability issues. Silicification of fibrin networks appears as a promising strategy not only to address these limitations but also to take advantage of the bioactivity of Si. However, it raises the question of the influence of silica sources on fibrin self-assembly.

First proteomic analyses of the dorsal and ventral parts of the Sepia officinalis cuttlebone.

Unlabelled: Protein compounds constituting mollusk shells are known for their major roles in the biomineralization processes. These last years, a great diversity of shell proteins have been described in bivalves and gastropods allowing a better understanding of the calcification control by organic compounds and given promising applications in biotechnology. Here, we analyzed for the first time the organic matrix of the aragonitic Sepia officinalis shell, with an emphasis on protein composition of two different structures: the dorsal shield and the chambered part.

High-resolution structural and elemental analyses of calcium storage structures synthesized by the noble crayfish Astacus astacus.

During premolt, crayfish develop deposits of calcium ions, called gastroliths, in their stomach wall. The stored calcium is used for the calcification of parts of the skeleton regularly renewed for allowing growth. Structural and molecular analyses of gastroliths have been primarily performed on three crayfish species, Orconectes virilis, Procambarus clarkii, and more recently, Cherax quadricarinatus.

Calcium Deposits in the Crayfish, Cherax quadricarinatus: Microstructure Versus Elemental Distribution.

The crayfish Cherax quadricarinatus stores calcium ions, easily mobilizable after molting, for calcifying parts of the new exoskeleton. They are chiefly stored as amorphous calcium carbonate (ACC) during each premolt in a pair of gastroliths synthesized in the stomach wall. How calcium carbonate is stabilized in the amorphous state in such a biocomposite remains speculative.

Alkaloids in marine algae.

This paper presents the alkaloids found in green, brown and red marine algae. Algal chemistry has interested many researchers in order to develop new drugs, as algae include compounds with functional groups which are characteristic from this particular source. Among these compounds, alkaloids present special interest because of their pharmacological activities.

Loliolide in marine algae.

Loliolide content was determined in 13 marine algae including red, brown and green algae collected from the Black Sea, the Dardanelles and the Aegean Sea. Identification and quantification were performed by gas chromatography-mass spectrometry. The loliolide content in green alga is 1.

Hairpin ribozyme catalysis: a surface-enhanced Raman spectroscopy study.

The existence of an "RNA world" as an early step in the history of life increases the interest for the characterization of these biomolecules. The hairpin ribozyme studied here is a self-cleaving/ligating motif found in the minus strand of the satellite RNA associated with Tobacco ringspot virus. Surface-enhanced Raman spectroscopy (SERS) is a powerful tool to study trace amounts of RNA.

Characterization of shrimp shell deproteinization.

The aim of this paper was to contribute to the interpretation of the mechanism of shrimp shell deproteinization. We used amino acid analysis to quantify the amount of proteins remaining in chitin. NaOH 1 M was added to a demineralized shrimp shell powder with a solution-to-solid ratio of 15 mL/g at ambient temperature.

Optimization of chitin extraction from shrimp shells.

The aim of this paper is to define optimal conditions for the extraction of chitin from shrimp shells. The kinetics of both demineralization and deproteinization with, in the latter case, the role of temperature are studied. The characterization of the residual calcium and protein contents, the molecular weights, and degrees of acetylation (DA) allows us to propose the optimal conditions as follows.