Absorption, Distribution and Excretion
/ Phosphate is absorbed from the gastrointestinal tract and secreted in small amounts. The transport of phosphate from the intestinal lumen is an active, energy-dependent process influenced by various factors. …Vitamin D stimulates phosphate absorption; this effect has been reported to precede its effect on calcium ion transport. In adults, approximately two-thirds of ingested phosphate is absorbed, and almost all absorbed phosphate is excreted in urine. In growing children, the phosphate balance is positive. Children have higher plasma phosphate concentrations than adults. This “hyperphosphatemia” reduces the affinity of hemoglobin for oxygen and is considered an explanation for physiological “anemia” in children. /Phosphate/

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Metabolism/Metabolites
Phosphate metabolism defects are present in many diseases. Rickets…Osteomalacia…Primary or secondary hyperparathyroidism…Chronic renal failure. /Phosphate/

Toxicity Summary
Identification and Uses: White amorphous or crystalline powder. Odorless and tasteless. Practically insoluble in alcohol and acetic acid, soluble in dilute hydrochloric acid and nitric acid. Slightly soluble in water. Used in the manufacture of fertilizers, phosphate compounds, emulsion glass, polishing powder and dental powder, porcelain, pottery, enamel; clarifying syrups; used as animal feed; used as an anti-caking agent; used in the textile industry. Used as a plastic stabilizer; used as a meat tenderizer; used as a food buffer; used as a calcium supplement in the medical field. In veterinary medicine, it is used as a dietary supplement and antacid. Used in the manufacture of luminescent materials. Human Exposure and Toxicity: Tricalcium phosphate is non-irritating; the toxic dose exceeds 2 g/kg. Skin sensitization is rare. Inhalation or aspiration may cause chemical pneumonia. Implantation of this substance may cause a foreign body reaction. Tricalcium phosphate is contraindicated for the treatment of hypocalcemia with hyperphosphatemia, which may occur in hypoparathyroidism and renal failure. Animal Studies: Tricalcium phosphate has no teratogenic effect on developing chicken embryos.

Calcium phosphate is a tasteless, white solid that sinks to the bottom of water and dissolves in it. (US Coast Guard, 1999)
Tricalcium phosphate is a type of calcium phosphate.
Calcium phosphate is commonly sold as an over-the-counter health supplement, antacid, or an additive in some toothpastes.
Calcium phosphate is the calcium salt of phosphoric acid and has a wide range of uses. It can be used to counteract exposure to the radioactive isotopes strontium and radium. When taken orally, calcium phosphate competes with radium (Ra-226) and strontium (Sr-90), thus hindering their absorption in the gastrointestinal tract.
See also: Tricalcium phosphate (note moved here).
Pharmaceutical Indications

Used as an over-the-counter calcium and phosphorus supplement, antacid, or source of calcium and phosphorus in toothpaste.
FDA Label
Mechanism of Action

The phosphate ions in calcium phosphate may react with hydrochloric acid in the stomach, thus neutralizing the pH. In toothpaste and throughout the body, calcium phosphate provides calcium and phosphate ions, supporting tooth remineralization and bone homeostasis, respectively. Elevated plasma calcium concentrations reduce calcium release from bone cells by decreasing parathyroid hormone (PTH) secretion. Calcium exerts its effects by stimulating G protein-coupled calcium receptors on the surface of parathyroid cells. Reduced calcium flow increases calcium deposition in bone, thus increasing bone mineral density. Decreased PTH secretion also reduces the amount of vitamin D metabolized into its active form—calcidiol. Since calcidiol increases the expression of calcium-dependent ATPase and transient receptor potential cation channel V subfamily member 6 (TRPV6), both of which are involved in intestinal calcium absorption, a decrease in calcidiol leads to reduced calcium absorption. Furthermore, when PTH secretion decreases, the TRPV5 channel, responsible for renal calcium reabsorption, is downregulated, thereby increasing the amount of calcium excreted via the kidneys. Another hormone, calmodulin, may also be involved in the reduced bone resorption during periods of elevated plasma calcium levels.

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Therapeutic Uses
... Primarily used as a gastric acid suppressant... A valuable source of calcium ions, especially when both calcium and phosphorus need to be supplemented simultaneously.
/Previous Uses/
…This oral calcium salt can be used to treat mild and occult hypocalcemic tetany and can be used as maintenance therapy….
This product is an excellent source of calcium and phosphorus and can be used to supplement calcium intake, such as during pregnancy and lactation, or as a calcium source for calcium deficiency diseases.
Calcium Supplements
For more complete data on the therapeutic uses of tricalcium phosphate (6 types), please visit the HSDB record page.

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Drug Warnings
…Contraindicated for the treatment of hypocalcemia. Hyperphosphatemia can be seen in hypoparathyroidism and renal failure.
Ceramic implant materials, including tricalcium phosphate, are biocompatible and are currently used to repair alveolar bone defects caused by periodontal disease, root canal infection, and resorption of residual alveolar ridge. However, in this case, the use of such materials resulted in persistent infection and further bone destruction. Therefore, the use of ceramic implant materials to accelerate periapical bone repair is not recommended in areas with chronic bacterial infection.

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Pharmacodynamics
Calcium phosphate reacts with stomach acid to increase the pH of the stomach. In toothpaste, it provides calcium and phosphate ions to support tooth remineralization. As a dietary supplement, it provides calcium and phosphate, both of which are important ions for maintaining bone homeostasis.

CA3O8P2

310.18

135.923

10103-46-5

12167-74-7 (tri-calcium salt);21063-37-6 (monetite);7757-93-9 (CaHPO4);10103-46-5 (Parent)

24456

White amorphous powder
White, crystalline powder
Two crystalline modifications are known, the high temperature alpha- and the low-temperature beta-form, transition temperature 110 °C.
Rhombohedral crystals /Whitlockite/

158ºC at 760mmHg

>450
1670 °C

0.981

0

8

0

13

36.8

0

[Ca+2].[Ca+2].[Ca+2].O=P([O-])([O-])[O-].O=P([O-])([O-])[O-]

QORWJWZARLRLPR-UHFFFAOYSA-H

InChI=1S/3Ca.2H3O4P/c;;;2*1-5(2,3)4/h;;;2*(H3,1,2,3,4)/q3*+2;;/p-6

tricalcium;diphosphate

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)

May dissolve in DMSO (in most cases), if not, try other solvents such as H2O, Ethanol, or DMF with a minute amount of products to avoid loss of samples

Note: Listed below are some common formulations that may be used to formulate products with low water solubility (e.g. < 1 mg/mL), you may test these formulations using a minute amount of products to avoid loss of samples.

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Injection Formulation 1: DMSO : Tween 80： Saline = 10 : 5 : 85 (i.e. 100 μL DMSO stock solution → 50 μL Tween 80 → 850 μL Saline)
*Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH ₂ O to obtain a clear solution.
Injection Formulation 2: DMSO : PEG300 ：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL DMSO → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline)
Injection Formulation 3: DMSO : Corn oil = 10 : 90 (i.e. 100 μL DMSO → 900 μL Corn oil)
Example: Take the Injection Formulation 3 (DMSO : Corn oil = 10 : 90) as an example, if 1 mL of 2.5 mg/mL working solution is to be prepared, you can take 100 μL 25 mg/mL DMSO stock solution and add to 900 μL corn oil, mix well to obtain a clear or suspension solution (2.5 mg/mL, ready for use in animals).

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Injection Formulation 4: DMSO : 20% SBE-β-CD in saline = 10 : 90 [i.e. 100 μL DMSO → 900 μL (20% SBE-β-CD in saline)]
*Preparation of 20% SBE-β-CD in Saline (4°C，1 week): Dissolve 2 g SBE-β-CD in 10 mL saline to obtain a clear solution.
Injection Formulation 5: 2-Hydroxypropyl-β-cyclodextrin : Saline = 50 : 50 (i.e. 500 μL 2-Hydroxypropyl-β-cyclodextrin → 500 μL Saline)
Injection Formulation 6: DMSO : PEG300 : castor oil : Saline = 5 : 10 : 20 : 65 (i.e. 50 μL DMSO → 100 μLPEG300 → 200 μL castor oil → 650 μL Saline)
Injection Formulation 7: Ethanol : Cremophor : Saline = 10： 10 : 80 (i.e. 100 μL Ethanol → 100 μL Cremophor → 800 μL Saline)
Injection Formulation 8: Dissolve in Cremophor/Ethanol (50 : 50), then diluted by Saline
Injection Formulation 9: EtOH : Corn oil = 10 : 90 (i.e. 100 μL EtOH → 900 μL Corn oil)
Injection Formulation 10: EtOH : PEG300：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL EtOH → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline)

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Oral Formulation 1: Suspend in 0.5% CMC Na (carboxymethylcellulose sodium)
Oral Formulation 2: Suspend in 0.5% Carboxymethyl cellulose
Example: Take the Oral Formulation 1 (Suspend in 0.5% CMC Na) as an example, if 100 mL of 2.5 mg/mL working solution is to be prepared, you can first prepare 0.5% CMC Na solution by measuring 0.5 g CMC Na and dissolve it in 100 mL ddH2O to obtain a clear solution; then add 250 mg of the product to 100 mL 0.5% CMC Na solution, to make the suspension solution (2.5 mg/mL, ready for use in animals).

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Oral Formulation 3: Dissolved in PEG400
Oral Formulation 4: Suspend in 0.2% Carboxymethyl cellulose
Oral Formulation 5: Dissolve in 0.25% Tween 80 and 0.5% Carboxymethyl cellulose
Oral Formulation 6: Mixing with food powders

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Note: Please be aware that the above formulations are for reference only. InvivoChem strongly recommends customers to read literature methods/protocols carefully before determining which formulation you should use for in vivo studies, as different compounds have different solubility properties and have to be formulated differently.

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 (Please use freshly prepared in vivo formulations for optimal results.)