Limits of Solid Solutions and Thermal Deformations in the L-Alanine–L-Serine Amino Acid System

Abstract

The limits of solid solutions and thermal deformations in the L-alanine–L-serine (L-ala–L-ser) amino acid system have been determined. Thirteen amino acid mixtures with various proportions of the components L-ser/L-ala were studied using powder X-ray diffraction techniques. It was found that the regions of solid solutions in the system are rather limited and cover less than 10 mol. % from each component side. The thermal behavior of the components L-ser and L-ala and the composition L-ser/L-ala = 90/10 were studied by temperature-resolved powder X-ray diffraction. The heating of L-ser and L-ala only causes thermal deformations, while two-phase mixtures with the 90/10 L-ser/L-ala ratio form solid solutions at elevated temperatures. Additionally, the parameters of the thermal deformation tensor for L-ser and L-ala were calculated, and the figures of their thermal expansion coefficients were plotted and analyzed. The study conducted is of high applicability, since amino acids are active components of various biological, geological, and technological processes, including those at elevated temperatures, and have numerous applications in life-science industries.

Thermal Deformations of Crystal Structures in the L-Aspartic Acid/L-Glutamic Acid System and DL-Aspartic Acid

“…The results of the present study were compared with data for other amino acids-such as L-valine, L-isoleucine, L-threonine, L-allo-threonine, and solid solutions of the latter two-that we had investigated previously [9,17,19].…”

“…The above results were compared with similar studies of thermal deformations for (1) the orthorhombic components in the L-threonine/L-allo-threonine (L-thr/L-athr) diastereomer system, and two solid solutions of both-namely, L-thr 0.34 ,L-athr 0.66 and Lthr 0.10 ,L-athr 0.90 [17]-and (2) the orthorhombic components in the L-alanine (L-ala) and L-serine (L-ser) enantiomer system [19]. It appears that heating resulted in increases in all orthorhombic parameters of L-glu and those of the solid solutions L-asp 0.25 ,L-glu 0.75 , L-thr 0.34 ,L-athr 0.66 , and L-thr 0.10 ,L-athr 0.90 , and in diminution of one of the parameters of the diastereomers L-thr and L-athr and the enantiomers L-ala and L-ser.…”

“…In our previous work, we investigated the thermal deformations of amino acid crystal structures and plotted the figures of CTEs for the following substances: (1) both components and two solid solutions formed in the L-threonine/L-allo-threonine diastereomer system [17], (2) both components and the non-equimolar discrete compound formed in the L-valine/L-isoleucine system [18], and (3) the components formed in the L-alanine/L-serine amino acids system [19].…”

Advances in Industrial Crystallization

“…solid-liquid, solid-solid) and the prevailing crystallization kinetics (like nucleation, growth, agglomeration, and breakage) [3,[7][8][9][10][11][12][13]. The diversity of the individual properties in the solid state [9,12] or the solidification process [10] of different products is one major challenge for each process engineer.…”

“…solid-liquid, solid-solid) and the prevailing crystallization kinetics (like nucleation, growth, agglomeration, and breakage) [3,[7][8][9][10][11][12][13]. The diversity of the individual properties in the solid state [9,12] or the solidification process [10] of different products is one major challenge for each process engineer. Hence, continuously novel processes [11,13] and process combinations [10] are discovered to deal with these various issues to fulfill the desired task, like product purity or productivity enhancement.…”