The influence of amino acids on the biomineralization of hydroxyapatite in gelatin

Eiden‐Assmann, Stefanie; Viertelhaus, Martin; Heiss, Alexander; Hoetzer, K.A; Felsche, J.

doi:10.1016/s0162-0134(02)00481-6

Cited by 70 publications

(48 citation statements)

References 21 publications

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“…Replacing HEPES from H x PO 4 x-3 to Ca 2+ precursor increased the transfection rate, demonstrating that organic buffers play a more intricate surface or complexing role than merely maintaining steady pH. This is in agreement with previous reports, including the one where the use of organic Tris and of inorganic phosphates as buffers led to precipitation of thoroughly different CaP phases [35]. Eliminating NaCl and precipitating CaP-pDNA at zero background ionic strength also increased the transfection rate, the reason being the absence of Na + ions, potent nucleation inhibitors when it comes to formation of apatite.…”

Section: Resultssupporting

confidence: 91%

Gene delivery using calcium phosphate nanoparticles: Optimization of the transfection process and the effects of citrate and poly( l -lysine) as additives

Khan

Ghosh

et al. 2016

Journal of Colloid and Interface Science

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Despite the long history of nanoparticulate calcium phosphate (CaP) as a non-viral transfection agent, there has been limited success in attempts to optimize its properties for transfection comparable in efficiency to that of viral vectors. Here we focus on the optimization of: (a) CaP nanoparticle precipitation conditions, predominantly supersaturation and Ca/P molar ratios; (b) transfection conditions, mainly the concentrations of the carrier and plasmid DNA; (c) the presence of surface additives, including citrate anion and cationic poly(L-lysine) (PLL). CaP nanoparticles significantly improved transfection with plasmid DNA encoding enhanced green fluorescent protein (eGFP) in pre-osteoblastic MC3T3-E1 cells compared to a commercial non-viral carrier. At the same time they elicited significantly lesser cytotoxicity than the commercial carrier. Plasmid DNA acted as a nucleation promoter, decreasing the nucleation lag time of metastable CaP solutions and leading to a higher rate of nucleation and a lower size of the precipitated particles. The degree of supersaturation (DS) of 15 was found to be more optimal for transfection than that of 12.5 or 17.5 and higher. Because CaP particles precipitated at DS 15 were spherical, while DS 17.5 and 21 yielded acicular particles, it was concluded that spherical particle morphologies were more conducive to transfection than the anisotropic ones. Even though the yield at DS 15 was 10 and 100 times lower than that at DS 17.5 and 21, respectively, transfection rates were higher using CaP nanoparticle colloids prepared at DS 15 than using those made at higher or lower DS, indicating that the right particle morphology can outweigh the difference in the amount of the carrier, even when this difference is close to 100x. In contrast to the commercial carrier, the concentration of CaP-pDNA delivered to the cells was directly proportional to the transfection rate. Osteosarcoma K7M2 cells were four times more easily transfectable with CaP nanoparticles than the MC3T3-E1 cells. The addition of citrate increased the transfection rate at lower concentrations; however, a complete redispersal of CaP-pDNA nanoparticles at higher concentrations of citrate coincided with a complete diminishment of transfection, implying the benefits of partial aggregation of CaP nanoparticles carrying pDNA. In contrast, PLL delayed transfection initially, but enhanced it at longer time points (≥ 96 h), leading to the conclusion that both citrate and PLL could exert positive effects on transfection: citrate if added at low concentrations and PLL to extend transfection over longer periods of time.

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Section: Resultssupporting

confidence: 91%

Gene delivery using calcium phosphate nanoparticles: Optimization of the transfection process and the effects of citrate and poly( l -lysine) as additives

Khan

Ghosh

et al. 2016

Journal of Colloid and Interface Science

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“…Such actions are believed to be related to their functional groups, including SO 4 2-, PO 4 3-and COO - [1,2]. Some natural amino acids, including sodium salts of poly(aspartic acid) and poly(glutamic acid), have been reported to influence both calcium carbonate and calcium phosphate crystal growth [3][4][5][6][7]. In contrast to less branched polypeptides, dendritic molecules, for example, poly(amidoamine) (PAMAM) dendrimers have attracted increasing interest for the regulation of inorganic compounds [8,9] due to their controllable sizes, well-defined structures, and multiple functional groups.…”

Section: Introductionmentioning

confidence: 99%

Effects of glutamic acid shelled PAMAM dendrimers on the crystallization of calcium phosphate in diffusion systems

et al. 2010

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Second generation poly(amidoamine) (PAMAM) dendrimers were synthesized and peripherally modified with glutamic acid (PAMAM-MG) as a shell. The effect of the dendrimers on the crystallization of different calcium phosphate compounds was investigated in both double and one way diffusion systems. It was found that the crystals of calcium phosphate showed tape-like morphology in the presence of PAMAM-MG, and the crystals' thickness and width decreased compared to those grown without dendritic molecules. Such a result might be due to the interaction of electric charges between dendritic molecules and octacalcium phosphate (Ca 8 H 2 (PO 4 ) 6 Á5H 2 O, OCP), which led to the adsorption of PAMAM-MG in the 100 and 010 surfaces of OCP. Moreover, PAMAM-MG showed an affinity for gelatin, and it could cause the formation of amorphous calcium phosphate (Ca 9 (PO 4 ) 6 ÁnH 2 O, ACP) at a concentration of 5 mg/mL of PAMAM-MG. These results suggest that PAMAM-MG could be used for regulating the morphology of OCP and changing the composition of minerals in gels.

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“…Their evidence suggests that components of blood including amino acid, peptide and/or protein or some composition of them were chemisorbed on the dendrite surfaces. Eiden-Abmann et al [75] studied the influence of amino acids on the formation and morphology of hydroxyapatite (calcium phosphate) in gelatin. They found that additions of amino acids (Asp, Glu, Ser, etc.)…”

Section: Justificationmentioning

confidence: 99%

On the Origin of Biological Functions

Umantsev¹

2011

JMP

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We consider the problem of structure and functions of the first forms of living matter and present a hypothesis that they were formed through a physico-chemical process known as dendritic crystallization. According to this hypothesis the branching, dendritic structures helped build living systems by lending them functions so that organic chemical evolution is just one natural consequence of the evolution of matter in the universe. We conclude that a self-replicating biological system with adaptation emerged from simple molecules using completely abiotic mechanism of formation, which acted simultaneously or intermittently at different places on the early Earth and created similar structures everywhere. The dendritic hypothesis of origin of the functions explains similarities in the living systems and supports the assumption of a 'second genesis of life'. The dendritic scenario does not need carbon/phosphorus-based solutes in water-based solutions, which may have important implications for exobiology and extraterrestrial origin-of-life scenarios. An experiment to test the hypothesis is suggested.

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The influence of amino acids on the biomineralization of hydroxyapatite in gelatin

Cited by 70 publications

References 21 publications

Gene delivery using calcium phosphate nanoparticles: Optimization of the transfection process and the effects of citrate and poly( l -lysine) as additives

Gene delivery using calcium phosphate nanoparticles: Optimization of the transfection process and the effects of citrate and poly( l -lysine) as additives

Effects of glutamic acid shelled PAMAM dendrimers on the crystallization of calcium phosphate in diffusion systems

On the Origin of Biological Functions

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