Absorption, Distribution and Excretion
/Ortho/ phosphate is absorbed from, and to a limited extent secreted into, the gastrointestinal tract. Transport of phosphate from the gut lumen is an active, energy-dependent process that is modified by several factors. ... Vitamin D stimulates phosphate absorption, an effect reported to precede its action on calcium ion transport. In adults, about two thirds of the ingested phosphate is absorbed, and that which is absorbed is almost entirely excreted into the urine. In growing children, phosphate balance is positive. Concentrations of phosphate in plasma are higher in children than in adults. This "hyperphosphatemia" decreases the affinity of hemoglobin for oxygen and is hypothesized to explain the physiological "anemia" of childhood. /Phosphates/

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Metabolism / Metabolites
A defect in phosphate metabolism occurs in a variety of diseases. ... Rickets ... Osteomalacia ... Primary or Secondary Hyperparathyroidism ... Chronic Renal Failure. /Phosphates/

Toxicity Summary
IDENTIFICATION AND USE: White amorphous, or crystaline powder. It is odorless and tasteless. It is practically insoluble in alcohol, and acetic acid, and soluble in dilute hydrochloric acid, and nitric acid. Slightly soluble in water. It is used in the manufacture of fertilizers, phosphate compounds, manufacture of milk glass, polishing and dental powders, porcelains, pottery, enameling; clarifying sugar syrups; in animal feeds; as noncaking agent; in textile industry. It is used as a stabilizer in plastics; in meat tenderizers; in food as a buffer and used in medical applications as a calcium replenisher. It veterinary medicine it is used as a dietary supplement and an antacid. It is used in the manufacture of luminescent materials. HUMAN EXPOSURE AND TOXICITY: Tricalcium phosphate is not irritating and toxic doses by ingestion would have to be more than 2 g/kg. Skin sensitization is unusual. Aspiration or inhalation could cause chemical pneumonitis. Implantation of material will cause foreign body reaction. Tricalcium phosphate is contraindicated in treatment of hypocalcemia with hyperphosphatemia which may occur in hypoparathyroidism and renal failure. ANIMAL STUDIES: Tricalcium phosphate exhibited no teratogenic effect in developing chicken embryos.

Calcium phosphate is an odorless white solid. Sinks and mixes with water. (USCG, 1999)
Tricalcium bis(phosphate) is a calcium phosphate.
Calcium phosphate is typically available as an over the counter supplement, antacid, or as an added ingredient in some toothpastes.
Calcium Phosphate is the calcium salt of phosphoric acid with widely used applications. This agent can be used as a countermeasure for exposure to strontium and radium radionuclides. Upon oral uptake, calcium phosphate competes for and blocks the absorption of radium (Ra-226) and strontium (Sr-90) in the gastrointestinal (GI) tract.
See also: Tribasic Calcium Phosphate (annotation moved to).

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Drug Indication
For use as an over the counter calcium and phosphate supplement, antacid, or a source of calcium and phosphate in toothpaste.
FDA Label

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Mechanism of Action
The phosphate ions in calcium phosphate likely react with hydrochloric acid in the stomach to neutralize the pH. In toothpaste and in systemic circulation, calcium phosphate provides a source of calcium and phosphate ions to support remineralization of the teeth and bone homeostasis respectively. The increase in plasma calcium reduces calcium flux from osteocyte activity by reducing the secretion of parathyroid hormone (PTH). Calcium does this by stimulating a G-protein coupled calcium receptor on the surface of parathyroid cells. The reduction in calcium flux increases the amount of calcium deposited in bone resulting in an increase in bone mineral density. The reduction in PTH secretion also reduces the amount of vitamin D metabolized to its active form, calcidiol. Since calcidiol increases the expression of calcium dependent ATPases and transient receptor potential cation channel subfamily V member 6 (TRPV6) both of which are involved in calcium uptake from the gut, a reduction in calcidiol results in less calcium absorption. Additionally, TRPV5, the channel responsible for calcium reabsorption in the kidney, is downregulated when PTH secretion is reduced thus increasing calcium excretion via the kidneys. Another hormone, calitonin, is likely involved in the reduction of bone resorption during periods of high plasma calcium.

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Therapeutic Uses
... CHIEFLY USED AS GASTRIC ANTACID ... VALUABLE SOURCE OF CALCIUM ION, ESPECIALLY WHEN IT IS DESIRED TO SUPPLY BOTH CALCIUM & PHOSPHORUS. /FORMER USE/
... /THIS/ ORALLY ADMIN CALCIUM ... /SALT/ CAN BE USED IN TREATMENT OF MILD & LATENT HYPOCALCEMIC TETANY & FOR MAINTENANCE THERAPY ... .
AN EXCELLENT SOURCE OF BOTH CALCIUM AND PHOSPHORUS USEFUL IN SUPPLEMENTING CALCIUM INTAKE, AS, FOR EXAMPLE, DURING PREGNANCY & LACTATION, OR AS SOURCE OF CALCIUM IN DISEASES OF CALCIUM DEFICIENCY.
Calcium replenisher
For more Therapeutic Uses (Complete) data for TRICALCIUM PHOSPHATE (6 total), please visit the HSDB record page.

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Drug Warnings
... CONTRAINDICATED IN TREATMENT OF HYPOCALCEMIA WITH HYPERPHOSPHATEMIA, WHICH MAY OCCUR IN HYPOPARATHYROIDISM AND RENAL FAILURE.
Ceramic implant materials, including tricalcium phosphate, are biocompatible and are currently being used to restore alveolar bone loss resulting from periodontal disease, endodontic infections, and residual alveolar ridge resorption. However, use of such a material in this case led to persistent infection and additional bone destruction. Thus, the use of a ceramic implant material to accelerate periapical bone repair is not recommended in areas where a chronic bacterial infection is present.

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Pharmacodynamics
Calcium phosphate reacts with acid in the stomach to raise the pH. In toothpaste it provides a source of calcium and phosphate ions to support remineralization of the teeth. As a supplement it provides a source of calcium and phospate, both of which are important ions in 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.)