Calcium citrate: An interesting organic calcium biomedical material / 中国组织工程研究

BACKGROUND: Calcium citrate has been used as calcium supplement, anticoagulant, anti-inflammatory agent and bone repair material in biomedical fields. OBJECTIVE: To describe the basic properties of calcium citrate, summarize and discuss the preparation process of calcium citrate and its main applications in biomedical field. METHODS: The research literature related to calcium citrate was searched on the Web of science, CNKI, Medline and other databases by computer. The main key words were “calcium citrate, bone repairing material, citrate and calcium phosphate” in English and “calcium citrate, bone repair materials” in Chinese. The searching time was from February 1920 to February 2020. RESULTS AND CONCLUSION: With the development and exploration of medical materials, it is necessary to change the original process to improve the biological activity of medical calcium citrate. It is an inevitable trend to obtain calcium citrate with various micro-morphology and high biological activity by controllable synthesis method. Calcium citrate is widely used as calcium supplement, anti-inflammatory agent, anticoagulant, bone repair material and other non-medical applications. Its advantages are being gradually explored by researchers. The preparation method plays a decisive role in the application field of calcium citrate. Different internal structure and size will bring different application fields, from the smallest chemical bond connection to the macroscopic morphology or mechanical properties. These factors may be the results of the dedicated exploration of researchers.

Preparation and evaluation of compressive strength and biocompatibilitywith biological calcium citrate cement / 西安交通大学学报(医学版)

Objective To produce the biological calcium citrate cement with fresh oyster shells, and investigate its compressive strength and biocompatibility so as to provide the experimental basis for clinical application of the material.Methods The compressive strength of biological calcium citrate cement was measured and its surface morphology was observed by SEM.The calcium release curve and pH value were measured in the simulated body fluid.Last, its biocompatibility was detected by cytotoxicity test.Results Biological calcium citrate cement produced by 0.33mL/g liquid solid ratio had the maximum compressive strength, and the crystal structure of the material was uniform and orderly.The determination of pH value showed that the degradation and absorption of biological calcium citrate cement did not significantly change the pH value of the body fluid.With gradual degradation of the material, the concentration of Ca2+ in the solution increased gradually.Cytotoxicity test showed that this material had good biocompatibility and no cytotoxicity.Conclusion Biological calcium citrate cement possesses strong compressive strength and good biocompatibility, and it can form a microenvironment with low in alkaline and high in calcium.

Calcium supplementation, bone mineral density and bone mineral content. Predictors of bone mass changes in adolescent mothers during the 6-month postpartum period

We determined the effect of calcium supplementation on bone mineral density (BMD) and bone mineral content (BMC) and identified predictors of bone mass changes in adolescent mothers 6 months postpartum. A prospective, analytical, clinical study was performed in adolescent mothers (≤19 years old; n=37) from La Plata, Argentina. At 15 days postpartum, mothers were randomly assigned into one of two groups and started with calcium supplementation; one group received dairy products (932 mg Ca; n=19) and the other calcium citrate tablets (1000 mg calcium/day; n=18). Weight, height and dietary intake were measured and BMD was determined by DEXA at 15 days (baseline) and 6 months postpartum. BMC, total body BMD and BMD were assessed in lumbar spine, femoral neck, trochanter and total hip. Regression models were used to identify the relationship of total body BMD and BMC with independent variables (calcium supplementation, months of lactation, weight at 6 months, percent weight change, lean mass at 6 months, percent lean mass change, total calcium intake). Results showed that changes in BMD and BMC at the different sites were similar in both groups, and changes in percent body weight and total calcium intake were the main predictive factors. In conclusion, the effect of calcium was similar with either form of supplementation, i.e., dairy products or tablets, and changes in percent body weight and total calcium intake were predictors of total body BMD and BMC changes.

Suplementación con calcio, densidad mineral ósea y contenido mineral óseo. Predictores de cambios en la masa ósea en madres adolescentes a los 6 meses postparto. El objetivo del estudio fue determinar el efecto de dos formas de suplementare calcio sobre la densidad mineral ósea (DMO) y el contenido mineral óseo (CMO), e identificar predictores de cambios en la masa ósea en madres adolescentes a los 6 meses postparto. Se realizó un estudio prospectivo, analítico y clínico en madres adolescentes (≤19 años; n=37) de la ciudad de La Plata, Argentina. A partir de los 15 días postparto, las adolescentes fueron distribuidas al azar en 2 grupos y comenzaron con la suplementación con calcio; un grupo recibió productos lácteos (932 mg Ca; n=19) y el otro citrato de calcio (1000 mg calcio/día; n=18). Se midió peso, altura y consumo de alimentos y se determinó la DMO por DEXA a los 15 días (línea de base) y a los 6 meses postparto. También se determinó CMO, DMO corporal total y DMO de columna lumbar, cuello femoral, trocánter y cadera total. Se usaron modelos de regresión para identificar relaciones entre DMO corporal total y CMO con variables independientes (tipo de suplementación, meses de lactancia, peso a los 6 meses, porcentaje de cambio de peso, masa magra a los 6 meses, porcentaje de cambio de masa magra, consumo total de calcio). Los resultados muestran que los cambios en DMO y CMO en los distintos sitios fueron similares en ambos grupos, y que los cambios en los porcentajes de peso corporal e ingesta total de calcio fueron los principales factores predictivos. En conclusión, el efecto del calcio fue similar tanto con productos lácteos como con comprimidos. Los cambios porcentuales en peso corporal e ingesta total de calcio resultaron factores predictivos de los cambios de la DMO corporal total y el CMO.

Anticaries effect of dentifrices with calcium citrate and sodium trimetaphosphate

Because of the growing concerns regarding fluoride ingestion by young children and dental fluorosis, it is necessary to develop new dentifrices. OBJECTIVE: The aim of this study was to evaluate the effect of dentifrices with calcium citrate (Cacit) and sodium trimetaphosphate (TMP) on enamel demineralization. MATERIAL AND METHODS: Enamel blocks (n=70), previously selected through surface hardness analysis, were submitted to daily treatment with dentifrices diluted in artificial saliva and to a pH-cycling model. The fluoride concentration in dentifrices was 0, 250, 450, 550, 1,000 and 1,100 µg F/g. CrestTM was used as a positive control (1,100 mg F/g). Cacit (0.25 percent) and TMP (0.25 percent) were added to dentifrices with 450 and 1,000 µg F/g. Surface hardness was measured again and integrated loss of subsurface hardness and fluoride concentration in enamel were calculated. Parametric and correlation tests were used to determine difference (p<0.05) and dose-response relationship between treatments. RESULTS: The addition of Cacit and TMP did not provide a higher fluoride concentration in enamel, however it reduced (p<0.05) mineral loss when compared to other dentifrices; the dentifrice with Cacit and TMP and a low fluoride concentration presented similar results when compared to a dentifrice with 1,100 mg F/g (p>0.05). CONCLUSIONS: Dentifrices with 450 and 1,000 µg F/g, Cacit and TMP were as effective as a gold standard one.

Eficiencia del proceso de lavado en la obtención del citrato de calcio y magnesio a escala de banco / Effectiveness of washout process to obtain calcium and magnesium citrate at bench scale

Como parte de la optimización del proceso tecnológico para obtener citrato de calcio y magnesio a partir de dolomitas, se estudió a escala de banco la etapa de lavado para disminuir el contenido de àcido cítrico libre. Las variantes de lavado estudiadas permitieron disminuir el contenido de àcido cítrico libre por debajo del 3 por ciento, mientras que los valores de calcio y magnesio son similares a los del lote antes de realizar el proceso de lavado. Por otro lado, el estudio toxicológico en ratas, comprobó que los lotes a los cuales se les aplicó las diferentes variantes de lavado no provocaron irritabilidad gástrica a las dosis de 2 000 mg/kg de peso corporal, por lo que se puede afirmar que el proceso de lavado establecido es adecuado para garantizar la calidad de la materia prima.

As part of the technological process optomization to obtain calcium citrate and magnesium from dolomites, we studied at bench scale, the washout stage to decrease the free citric acid content. Washout variants allowed to decrease the free citric acid content under 3 percent, whereas the calcium and magnesium values are similar to those of batch before to carry out the wahout process. On the other hand, toxicity study in rats, proved that the batches where different washout variables were applied not provoke gastric irritability at doses of 2 000 mg/kg of body weight confirming that above mentioned established process is approproate to guarantee the raw material quality.

Comparison of Six Methods Ameliorating the Disintegration of Calcium Citrate Tablet / 中国药房

OBJECTIVE: To compare several METHODS: ameliorating the disintegration of calcium citrate tablet .METHODS: To prepare calcium citrate tablet by six different METHODS: and to determine and evaluate the prepared tablet in respect to the apperance,difference in weight of tablets,hardness,friability and stability .RESULTS:The disintegration was not significantly ameliorated by increasing disintegrant or decreasing lubricant .The hardness was decreased and the friability was increased by decreasing the amount of binder or adding more disintegrant or crushing calcium citrate to powder.The two latter METHODS: increased the difference in weight of tablets.CONCLUSION:The optimal method to ameliorate the disintegration is to diminish the grain diameter and the other parameters of quality is able to be up to the standard.