Effects of L‐Serine and L‐Proline on Crystallization Kinetics of Calcium Pyrophosphate Dihydrate

Abstract

Calcium pyrophosphate dihydrate (CPPD) crystallization was investigated in a mixed‐suspension mixed‐product removal (MSMPR)‐type crystallizer in the presence of the amino acids L‐serine and L‐proline as additives. Scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and zeta potential analysis were applied for characterization of the crystals obtained. CPPD crystals obtained in pure media consisted of aggregated particles which included plate‐like structures and rod‐shaped crystals. However, it was observed that agglomeration and breakage tendency on CPPD crystals obtained in the presence of amino acids were remarkable. The population balance equation for CPPD crystals was resolved with numerical analysis considering aggregation and breakage steps. The predominant mechanism was the breakage for CPPD crystallization in the presence of amino acids.

Multidimensional Population Balance Modeling for Pathological Calcium Pyrophosphate Dihydrate Crystals in the Presence of Amino Acids

“…The effects of L ‐Lys and L ‐Thr amino acids on the CPPD crystal morphology are similar to the tendency of agglomeration and breakage in cases where L ‐Ser, L ‐Pro, and other amino acids were used in our preceding studies . The SEM images in Fig.…”

“…CPPD (Ca 2 P 2 O 7 ·2H 2 O) was obtained from the reaction of calcium chloride dihydrate (CaCl 2 ·2H 2 O) and sodium pyrophosphate decahydrate (Na 4 P 2 O 7 ·10H 2 O) under conditions close to general physiological conditions. The experiments were performed in the MSMPR crystallizer under the conditions described comprehensively in our previous study . To summarize, the operating conditions were set at 37 °C, 650 rpm stirrer rate, and 4 h mean residence time ( τ ).…”

“…Studies on the assessment of the results acquired from continuous or semi-continuous operations are less common in literature [9,10]. In our preceding study, the macroscopic population balance equation at one dimension suggested by Raphael et al was re-evaluated considering agglomerated particles by some acceptances [6,11]. In this paper, 2D-PBE was reconstructed under steady-state conditions based on the previous model equation and the two-dimensional mathematical expressions defined for both growth and breakage (Eq.…”

“…Furthermore, the two‐directional (2D‐) PBE was constituted by taking into consideration the growth and the breakage steps of agglomerates and numerically solved by using MATLAB. In this paper, the model used in our previous study was rearranged according to the growth and breakage in two directions . The growth was expressed in two directions depending on the particle sizes by an exponential‐hyperbolic function similar to the M4 model in literature .…”

Estimation of Kinetics for Batch Cooling Crystallization by Focused‐Beam Reflectance Measurements

“…These images were taken with an optical microscope (Olympus SZX10) during batch crystallization at a cooling rate of 0.4 °C min −1 . Introduction of an equation for breakage or agglomeration may decrease the deviations between simulated values and observed ones . Moreover, breakage and agglomeration make crystal shape largely different from the set shape, which was assumed to cause severe error.…”