Title of Invention	A COMPOSITION CONTAINING NANOPHASE CALCIUM DEFICIENT HYDROXYAPATITE WITH MG, SR AND SI SYNTHESIZED FROM EGG SHELL BY MICROWAVE PROCESSING
Abstract	A method of preparing a composition containing nanophase calcium deficient hydroxyapatite with Mg, Sr and Si synthesized ,from eggshell by microwave processing comprising the steps of thoroughly cleaning eggshell wastes and heating the same to 900°C about two hours to remove organic waste and to decompose the calcium carbonate content of the eggshell, during heating, to calcium oxide; cooling the same under exposure to atmosphere, to convert the calcium oxide to calcium hydroxide; grinding the said calcium hydroxide and mixing it with distilled water to obtain a suspension adding non-stoichiometric amount of a phosphate salt with Ca/P ratio 1.5 to the said suspension and heating the same in a domestic microwave oven for 40 minutes, the power of the oven being adjusted to avoid overflow of-the solution during boiling, the resulting paste like product being thereafter thoroughly washed with hot water and dried in an oven to yield the said composition.

Title of Invention

A COMPOSITION CONTAINING NANOPHASE CALCIUM DEFICIENT HYDROXYAPATITE WITH MG, SR AND SI SYNTHESIZED FROM EGG SHELL BY MICROWAVE PROCESSING

Abstract

A method of preparing a composition containing nanophase calcium deficient hydroxyapatite with Mg, Sr and Si synthesized ,from eggshell by microwave processing comprising the steps of thoroughly cleaning eggshell wastes and heating the same to 900°C about two hours to remove organic waste and to decompose the calcium carbonate content of the eggshell, during heating, to calcium oxide; cooling the same under exposure to atmosphere, to convert the calcium oxide to calcium hydroxide; grinding the said calcium hydroxide and mixing it with distilled water to obtain a suspension adding non-stoichiometric amount of a phosphate salt with Ca/P ratio 1.5 to the said suspension and heating the same in a domestic microwave oven for 40 minutes, the power of the oven being adjusted to avoid overflow of-the solution during boiling, the resulting paste like product being thereafter thoroughly washed with hot water and dried in an oven to yield the said composition.

Full Text	THE PATENTS ACT 1970 COMPLETE SPECIFICATION SECTION 10 A COMPOSITION CONTAINING NANOPHASE CALCIUM DEFICIENT HYDROXYAPATITE WITH Mg, Sr and Si SYNTHESIZED FROM EGG SHELL BY MICROWAVE PROCESSING INDIAN INSTITUTE OF TECHNOLOGY, IIT P.O., CHENNAI600036. INDIA, AN AUTONOMOUS BODY SET UP BY GOVERNMENT OF INDIA UNDER AN ACT OF PARLIAMENT THE FOLLOWING SPECIFICATION PARTICULARLY DESCRIBES THE NATURE OF THIS INVENTION AND THE MANNER IN WHICH IT IS TO BE PERFORMED: This invention relates to a composition containing nanophase calcium deficient hydroxyapatite with Mg, Sr and Si synthesized from eggshell by microwave processing. The mineral component of bone and teeth is essentially calcium deficient hydroxyapatite (CDHA) with Ca/P ratio of about 1.5, which is compositionally similar to bioresorbable tricalcium phosphate ((β-TCP, Ca3(PO4) while being structurally similar to the more stable stoichiometric hydroxyapatite (HA, Ca10(PO4)6(OH)2) of Ca/P = 1.67. The CDHA has higher specific surface area compared to HA and TCP and is highly soluble in water or body fluids to have reproducible seeding efficacy. The CDHA seems to be more efficient in inducing the formation of bone-like apatite than stoichiometric HA. Biological apatites (like in bone) are nanostructured crystals of dimension 20 nm in diameter and 50 nm long. Nanocrystalline HA has proved to be of greater biological efficacy in terms of osteohlast adhesion, proliferation, osseointegration and formation of new bone on its surface. The biological apatite also has other ions such as carbonate, hydrogen phosphate, magnesium, iron and also water molecules in very small or trace amounts. These ions are not only chemically present but most of them are structurally incorporated in the apatites. From bionics viewpoint, synthetic apatites to be used for repairing damaged hard tissues are expected to have characteristics closer to those of biological apatite in both composition and structure. The method of preparing the composition, according to this invention, comprises the steps of thoroughly cleaning eggshell wastes and heating the same to 900°C for about two hours to remove organic waste and to decompose the calcium carbonate content of the eggshell, during heating, to calcium oxide; cooling the same under 9 exposure to atmosphere, to convert the calcium oxide to calcium hydroxide; grinding the said calcium hydroxide and mixing it with distilled water to obtain a suspension; adding non-stoichiometric amount of a phosphate salt with Ca/P ratio 1.5 to the said suspension and heating the same in a domestic microwave oven for 40 minutes, the power of the oven being adjusted to avoid overflow of the solution during boiling, the resulting paste like product being thereafter thoroughly washed with hot water and dried in an oven to yield the said composition. The product was characterized by X-ray powder diffraction (XRD) method, Fourier transform infrared (FT-IR) spectroscopy and scanning electron microscope (SEM). The composition of the product has been analysed with X-ray fluorescence spectroscopy (XRF) and inductively coupled plasma — atomic emission spectroscopy (ICP-AES). Magnesium is also undoubtedly one of the most important bivalent ions associated with biological apatites. The mineralization is influenced by the presence of Mg2+ ions. Strontium has been shown to reduce the incidence of cavities in teeth and Sr2 + ion containing compounds have been used for the treatment of osteoporosis. Silicon is also important for bone formation and calcification. The amounts of the element such as Mg, Sr, Na and Si present in the eggshell were comparable with NIST-1400 standard hydroxyapatite reference material and the contents of bone ash (Mg 0.684 wt% and Sr 249 fig/g) and hence may be sufficient to induce the mineralization and other beneficial processes. Better bone bonding would be achieved with CDHA sample, as they are more close to bone mineral in composition, crystal structure, size and morphology. The elemental composition using ICP-AES. (wt/wt%) 5 The uniqueness of this process and the product are: 1). Utilization of eggshell waste for preparing value added biomaterial bioresorbable product. 2). Microwave processing has been adapted for processing of eggshell to nano CDHA. The process has advantage of producing 100 g in a single batch. 3). This route results in a product containing biologically active ions, which makes it superior for orthopedic and dental applications. 4

Full Text

THE PATENTS ACT 1970
COMPLETE SPECIFICATION SECTION 10
A COMPOSITION CONTAINING NANOPHASE CALCIUM DEFICIENT HYDROXYAPATITE WITH Mg, Sr and Si SYNTHESIZED FROM EGG SHELL BY
MICROWAVE PROCESSING
INDIAN INSTITUTE OF TECHNOLOGY, IIT P.O., CHENNAI600036. INDIA, AN AUTONOMOUS BODY SET UP BY GOVERNMENT OF INDIA UNDER AN ACT OF PARLIAMENT
THE FOLLOWING SPECIFICATION PARTICULARLY DESCRIBES THE NATURE OF THIS INVENTION AND THE MANNER IN WHICH IT IS TO BE PERFORMED:

This invention relates to a composition containing nanophase calcium deficient hydroxyapatite with Mg, Sr and Si synthesized from eggshell by microwave processing.
The mineral component of bone and teeth is essentially calcium deficient hydroxyapatite (CDHA) with Ca/P ratio of about 1.5, which is compositionally similar to bioresorbable tricalcium phosphate ((β-TCP, Ca3(PO4) while being structurally similar to the more stable stoichiometric hydroxyapatite (HA, Ca10(PO4)6(OH)2) of Ca/P = 1.67. The CDHA has higher specific surface area compared to HA and TCP and is highly soluble in water or body fluids to have reproducible seeding efficacy. The CDHA seems to be more efficient in inducing the formation of bone-like apatite than stoichiometric HA.
Biological apatites (like in bone) are nanostructured crystals of dimension 20 nm in diameter and 50 nm long. Nanocrystalline HA has proved to be of greater biological efficacy in terms of osteohlast adhesion, proliferation, osseointegration and formation of new bone on its surface. The biological apatite also has other ions such as carbonate, hydrogen phosphate, magnesium, iron and also water molecules in very small or trace amounts. These ions are not only chemically present but most of them are structurally incorporated in the apatites. From bionics viewpoint, synthetic apatites to be used for repairing damaged hard tissues are expected to have characteristics closer to those of biological apatite in both composition and structure.
The method of preparing the composition, according to this invention, comprises
the steps of thoroughly cleaning eggshell wastes and heating the same to 900°C for about two hours to remove organic waste and to decompose the calcium carbonate content of the eggshell, during heating, to calcium oxide; cooling the same under
9

exposure to atmosphere, to convert the calcium oxide to calcium hydroxide; grinding the said calcium hydroxide and mixing it with distilled water to obtain a suspension; adding non-stoichiometric amount of a phosphate salt with Ca/P ratio 1.5 to the said suspension and heating the same in a domestic microwave oven for 40 minutes, the power of the oven being adjusted to avoid overflow of the solution during boiling, the resulting paste like product being thereafter thoroughly washed with hot water and dried in an oven to yield the said composition.
The product was characterized by X-ray powder diffraction (XRD) method, Fourier transform infrared (FT-IR) spectroscopy and scanning electron microscope (SEM). The composition of the product has been analysed with X-ray fluorescence spectroscopy (XRF) and inductively coupled plasma — atomic emission spectroscopy (ICP-AES).
Magnesium is also undoubtedly one of the most important bivalent ions associated with biological apatites. The mineralization is influenced by the presence of Mg2+ ions. Strontium has been shown to reduce the incidence of cavities in teeth and Sr2 + ion containing compounds have been used for the treatment of osteoporosis. Silicon is also important for bone formation and calcification. The amounts of the element such as Mg, Sr, Na and Si present in the eggshell were comparable with NIST-1400 standard hydroxyapatite reference material and the contents of bone ash (Mg 0.684 wt% and Sr 249 fig/g) and hence may be sufficient to induce the mineralization and other beneficial processes. Better bone bonding would be achieved with CDHA sample, as they are more close to bone mineral in composition, crystal structure, size and morphology. The elemental composition using ICP-AES. (wt/wt%)

5

The uniqueness of this process and the product are:
1). Utilization of eggshell waste for preparing value added biomaterial bioresorbable product.
2). Microwave processing has been adapted for processing of eggshell to nano
CDHA. The process has advantage of producing 100 g in a single batch.
3). This route results in a product containing biologically active ions, which
makes it superior for orthopedic and dental applications.
4

Documents:

0848-che-2006 abstract-duplicate.pdf

0848-che-2006 cliam-duplicate.pdf

0848-che-2006 description (complete)-duplicate.pdf

848-che-2006 abstract.pdf

848-che-2006 claims.pdf

848-che-2006 complete description.pdf

848-che-2006 correspondance -others.pdf

848-che-2006 form 1.pdf

848-che-2006 form 26.pdf

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Patent Number

232313

Indian Patent Application Number

848/CHE/2006

PG Journal Number

13/2009

Publication Date

27-Mar-2009

Grant Date

16-Mar-2009

Date of Filing

15-May-2006

Name of Patentee

INDIAN INSTITUTE OF TECHNOLOGY

Applicant Address

IIT P.O. CHENNAI 600 036,

Inventors:

#	Inventor's Name	Inventor's Address
1	DR. TIRUCHIRAPPALLI SUBRAMAINIAM SAMPATH KUMAR	DEPARTMENT OF METALLURGICAL & MATERIALS ENGG., IIT, CHENNAI 600 036,
2	DR. SEKHARIPURAM KRISHNAMOORTHY SESHADRI	DEPARTMENT OF METALLURGICAL & MATERIALS ENGG., IIT, CHENNAI 600 036,
3	ARJUNAN SIDDHARTHAN	DEPARTMENT OF METALLURGICAL & MATERIALS ENGG., IIT, CHENNAI 600 036,

PCT International Classification Number

C01F

PCT International Application Number

N/A

PCT International Filing date

PCT Conventions:

#	PCT Application Number	Date of Convention	Priority Country
1			NA