Claims:WE CLAIM:

1. A process for manufacturing of implants of magnesium-based biocompatible composite materials, comprising:
melting a first set of metal and second set of one or more metals at temperature ranging from 650 to 700°C for a duration of 1 hour,
wherein the first set of metal comprises magnesium and the second set of one or more metals comprises zinc and calcium;
mixing a molten first set of metal with a molten second set of one or more metals in a predefined ratio to form a master alloy;
nano-reinforcing the master alloy using nano-polymers of one of calcium phosphate and gold doped HAp,
wherein the nano-reinforcement being carried out by stirring a mixture of molten master alloy and nano-polymers of one of calcium phosphate and gold doped HAp using high rpm stirrer at a predefined rpm to obtain a homogenous mixture of nano-reinforced master alloy;
pouring the homogenous mixture of nano-reinforced master alloy into a preheated mould to obtain a predefined shape of implant; and
squeeze casting molten homogenous mixture of nano-reinforced master alloy to obtain predefine shape or billets of magnesium-based biocompatible material.
2. The process as claimed in claim 1, wherein the predefined ratio of the master alloy representative of mixture of molten magnesium mixed with the molten zinc and calcium is 92:5:3.

3. The process as claimed in claim 1, wherein the nano polymers of calcium phosphate comprise average size of 100 nm to 500nm and a flat plate shape self-assembled into a flower shape morphology.

4. The process as claimed in claim 1, wherein the nano polymers of gold doped HAp comprise average size of 50 nm to 100nm and a flakes shape morphology.

5. The process as claimed in claim 1, wherein the pre-defined rpm of the high rpm stirrer being used for nano-reinforcement of master alloy is 1000 rpm.

6. The process as claimed in claim 1, wherein stirring the mixture of molten master alloy and nano-polymers of one of calcium phosphate and gold doped HAp using high rpm stirrer is carried for a duration of 10 to 30 minutes.

7. The process as claimed in claim 1, wherein the homogenous mixture of nano-reinforced master alloy comprises 92 to 97 wt % the first set of metal, 1 to 6 wt % the second set of one or more metals, and 1 to 3 wt % the nano-polymers of one of calcium phosphate and gold doped HAp.

8. The process as claimed in claim 1, wherein the homogenous mixture of nano-reinforced master alloy comprises 92 wt % the first set of metal, 5 wt % the second set of one or more metals, and 3 wt % the nano-polymers of one of calcium phosphate and gold doped HAp.

9. The process as claimed in claim 1, wherein the squeeze casting of the homogenous mixture of molten master alloy reinforced with nano-polymers of calcium phosphate is carried at temperature raging between 650 to 700°C and at 100 MPa pressure with tolerance of ± 10 for a duration of 10 minutes.

10. An implant biomaterial, comprising:
92 to 97 wt % first set of metal;
1 to 6 wt % second set of one or more metals; and
1 to 3 wt % nano-polymers of one of calcium phosphate and gold doped HAp.
11. The implant biomaterial as claimed in claim 10, wherein the first set of metal comprises magnesium.

12. The implant biomaterial as claimed in claim 10, wherein the second set of one or more metals comprises zinc and calcium, wherein zinc account for 3 to 6 wt% and calcium account for 1 to 3 wt%.

13. The implant biomaterial as claimed in claim 10, wherein the nano polymers of calcium phosphate comprise average size of 100 nm to 500nm and a flat plate shape self-assembled into a flower shape morphology.

14. The implant biomaterial as claimed in claim 10, wherein the nano polymers of gold doped HAp comprise average size of 50 to 100 nm and a flakes shape morphology.

15. An implant biomaterial, comprising:
92 wt% first set of metal,
wherein the first set of metal comprises magnesium;
5 wt % second set of one or more metals,
wherein the second set of one or more metal comprises zinc and calcium;
3 wt % nano-polymers of calcium phosphate,
wherein the nano polymers of calcium phosphate comprise average size of 100 nm to 500nm and a flat plate shape self-assembled into a flower shape morphology, and
wherein the nano polymers of gold doped HAp comprise average size of 50 to 100 nm and a flakes shape morphology.

Dated this 20th Day of February 2020


Vidya Bhaskar Singh Nandiyal
Patent Agent (IN/PA-2912)
Agent for applicant
, Description:FIELD OF THE INVENTION
[0001] Embodiments of the present disclosure relates to a biocompatible material and more particularly it relates to a process for manufacturing of biocompatible products using magnesium-based hybrid composite for orthopaedic applications.

BACKGROUND

[0002] Nowadays implants are used as an alternative for replacement of body parts or supporting the body parts during corrective surgery. An ideal bone implant should yield characteristic parameters, such as osteoconductivity in order to guide bone inside and around the implant, macroporosity to assist the ingrowth of bone cells, the ability to direct drugs and growth factors to the target cells, biodegradability to enable for bone remodeling, in addition to the mechanical stability and ease of handling. Thus, a material to be used for implant plays an irreplaceable role in the bone repair and replacement.

[0003] Currently, bone implants use solid metal, most often titanium, stainless steel and cobalt chromium alloy. These integrate well with the body's immune system, but these are lot stiffer than natural bone, which makes implant to carry a lot more weight than the adjacent bone. This can cause the bone to deteriorate, where the metal is in the long-term use will wear or corrosion, may produce toxic metal ions or particles, causing inflammation in the body and the implant to get damaged and need a replacement.

[0004] These materials are non-degradable, thus fracture with the bone plate, bone pins and bone screws, must be removed carrying the second operation for bone tissue repair. Repetition of the surgery not only increase the cost of health care system, but also increases the suffering of the patients.

[0005] Recent studies, using bioactive ceramics based on calcium phosphate materials primarily hydroxyapatite, tricalcium phosphate and mg-based material, because of their resemblance to the mineral portion of the bone and lower density, and these materials comply to characteristics of biodegradability.

[0006] These materials can be manufactured via phase separation, chemical etching, particulate leaching, electro-spinning, 3-D printing and squeeze casting techniques.

[0007] However, there is need of simple and cost-effective process to produce biocompatible material having high intermetallic bond strength and uniform distribution in the lattice. The process improves overall strength of the implants while imparting lighter weight as compared to conventional implants like Titanium alloy and steel alloy which are heavy in weight.

[0008] Present disclosure providing the simple and convinient process for manufacturing the implants from magnesium-based biocompatible material having high strength for biomedical application.
BRIEF DESCRIPTION
[0009] In accordance with an embodiment of the disclosure, a process for manufacturing of implants of magnesium-based biocompatible material is provided. The process includes melting a first set of metal and a second set of one or more metals. The first set of metal include magnesium and the second set of one or more metals include zinc and calcium. The process also includes mixing a molten first set of metal with a molten second set of one or more metals in a predefined ratio to form a master alloy. The process also includes nano-reinforcing the master alloy using nano-polymers of calcium phosphate or gold doped hydroxyapatite (HAp). The reinforcement being carried out by stirring a mixture of molten master alloy and nano-polymers of calcium phosphate or gold doped hydroxyapatite (HAp) using high rpm stirrer to obtain a homogenous mixture of nano-reinforced master alloy. The process also includes pouring the nano-reinforced master alloy into a preheated mould to obtain a predefined shape of implant. The process further includes squeeze casting the homogenous mixture of molten master alloy reinforced with nano-polymers of calcium phosphate or gold doped hydroxyapatite (HAp) to obtain predefine shape or billets of magnesium-based biocompatible material.

[0010] In another embodiment of the present invention, an implant biomaterial is provided. The implant biomaterial includes 92 wt% first set of metal, 5 wt % second set of one or more metals, and 3 wt % nano-polymers of calcium phosphate or gold doped hydroxyapatite (HAp).

[0011] To further clarify the advantages and features of the present invention, a more particular description of the invention will follow by reference to specific embodiments thereof, which are illustrated in the appended figures. It is to be appreciated that these figures depict only typical embodiments of the invention and are therefore not to be considered limiting in scope. The invention will be described and explained with additional specificity and detail with the appended figures.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] The disclosure will be described and explained with additional specificity and detail with the accompanying figures in which:

[0013] FIG. 1 illustrates a flow chart representing steps involved in a process for manufacturing the implants from magnesium-based biocompatible material in accordance with an embodiment of the present disclosure.

[0001] Further, those skilled in the art will appreciate that elements in the figures are illustrated for simplicity and may not have necessarily been drawn to scale. Furthermore, in terms of the construction of the device, one or more components of the device may have been represented in the figures by conventional symbols, and the figures may show only those specific details that are pertinent to understanding the embodiments of the present disclosure so as not to obscure the figures with details that will be readily apparent to those skilled in the art having the benefit of the description herein.

DETAILED DESCRIPTION
[0014] For the purpose of promoting an understanding of the principles of the disclosure, reference will now be made to the embodiment illustrated in the figures and specific language will be used to describe them. It will nevertheless be understood that no limitation of the scope of the disclosure is thereby intended. Such alterations and further modifications in the illustrated system, and such further applications of the principles of the disclosure as would normally occur to those skilled in the art are to be construed as being within the scope of the present disclosure.

[0015] The terms "comprises", "comprising", or any other variations thereof, are intended to cover a non-exclusive inclusion, such that a process or method that comprises a list of steps does not include only those steps but may include other steps not expressly listed or inherent to such a process or method. Appearances of the phrase "in an embodiment", "in another embodiment" and similar language throughout this specification may, but not necessarily do, all refer to the same embodiment.

[0016] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this disclosure belongs. The kit and examples provided herein are only illustrative and not intended to be limiting.

[0017] In the following specification and the claims, reference will be made to a number of terms, which shall be defined to have the following meanings. The singular forms “a”, “an”, and “the” include plural references unless the context clearly dictates otherwise.

[0018] Embodiments of the present disclosure relate to a process for manufacturing of high strength magnesium-based implants for biomedical application. Present disclosure provides a simple and efficient process for manufacturing the implants using a biocompatible material. The biocompatible material having high intermetallic bond strength and uniform distribution in the lattice. The process improves overall strength of the implants while imparting lighter weight as compared to conventional implants like Titanium alloy and steel alloy which are heavy in weight.

[0019] FIG. 1 illustrates a flow chart representing steps involved in a process for manufacturing the implants from magnesium-based biocompatible material in accordance with an embodiment of the present disclosure. The process mainly comprises, nano reinforcement of magnesium-based biocompatible material with nano-polymers of calcium phosphate or gold doped hydroxyapatite (HAp) to obtain biocompatible and biodegradable implant for biomedical applications.

[0020] The process for manufacturing of implants of magnesium-based biocompatible material begins with melting a first set of metal and a second set of one or more metals at temperature ranging from 650 to 700°C for a duration of 1 hour is carried out at step 102. The first set of metal includes magnesium and the second set of one or more metals include zinc and calcium.

[0021] In an embodiment, a molten first set of metal and a molten second set of one or more metals are mixed in a predefined ratio to obtain a master alloy at step 104. The predefined ratio of the master alloy being representative of mixture of molten magnesium mixed with the molten zinc and calcium is 92:5:3.

[0022] In an embodiment, nano-reinforcement of the master alloy obtained from step 104 is carried out using nano-polymers of calcium phosphate or gold doped hydroxyapatite (HAp) at step 106. As used herein, the term “nano-reinforcement” refers to reinforcement or strengthening of materials using nanometer-size particles, platelets, or filaments. The nano polymers of calcium phosphate being used for nano-reinforcement comprise average size of 100 nm to 500nm and a flat plate shape self-assembled into a flower shape morphology. The nano polymers of gold doped HAp comprise average size of 50 nm to 100 nm and a flakes shape morphology.

[0023] In such embodiment, the reinforcement being carried out by stirring a mixture of molten master alloy and nano-polymers of calcium phosphate or gold doped hydroxyapatite (HAp) using high rpm stirrer to obtain a homogenous mixture of nano-reinforced master alloy, wherein the pre-defined rpm of the high rpm stirrer being used for nano-reinforcement of master alloy is 1000rpm. The stirring of mixture of molten master alloy and nano-polymers of calcium phosphate or gold doped hydroxyapatite (HAp) using high rpm stirrer is carried for a duration of 10 to 30 minutes.

[0024] In an embodiment, the homogenous mixture of nano-reinforced master alloy comprises 92 to 97 wt % of the first set of metal, 1 to 6 wt % of the second set of one or more metals, and 1 to 3 wt % of the nano-polymers of calcium phosphate or gold doped hydroxyapatite (HAp). The first set of metal includes magnesium and the second set of one or more metals include zinc and calcium.

[0025] In an exemplary embodiment, the homogenous mixture of nano-reinforced master alloy comprises 92 wt % of the first set of metal, 5 wt % of the second set of one or more metals, and 3 wt % of the nano-polymers of calcium phosphate or gold doped hydroxyapatite (HAp).

[0026] In an embodiment, the nano-reinforced master alloy is being poured into a preheated mould to obtain a predefined shape of implant at step 108. The predefined shaped of the implant may vary as per the requirements of patients.

[0027] In an embodiment, the nano-reinforced master alloy is given a predefined shape to obtain predefine shape or billets by squeeze casting at step 110. As used herein, the term “squeeze casting” refers to liquid metal forging or the process in which an alloy melt solidifies under the application of external pressure, in order to prevent the formation of shrinkage porosity. The squeeze casting of the homogenous mixture of molten master alloy reinforced with nano-polymers of calcium phosphate or gold doped hydroxyapatite (HAp) is carried at temperature raging between 650 to 700°C and at 100 MPa pressure with tolerance of ± 10 for a duration of 10 minutes. In such embodiment, the nano-reinforced molten alloy poured into the preheated mould is squeezed in the molten condition until it solidifies into desired shapes of the billet. The implants and billets so manufactured may include, but not limited to, bone implants, dental implant such as rods, discs, small screws and pins etc.

[0028] In another embodiment of the present invention, an implant biomaterial suitable for making implants is provided. The implant biomaterial includes a first set of metal, a second set of one or more metals and nano-polymers of calcium phosphate or gold doped hydroxyapatite (HAp) in predefined percentages. The nano polymers of calcium phosphate comprise average size of 100nm to 500nm and a flat plate shape self-assembled into a flower shape morphology. The nano polymers of gold doped hydroxyapatite (HAp) comprise average size of 50 nm to 100 nm and a flakes shape morphology.

[0029] In such embodiment, the first set of metal comprises magnesium and the second set of one or more metals comprises zinc and calcium, wherein the nano-polymer of calcium phosphate or gold doped hydroxyapatite (HAp) being used for nano-reinforcement of biomaterial. The implant biomaterial may include 92 to 97 wt % first set of one or more metals, 1 to 6 wt % second set of one or more metals and 1 to 3 wt % nano-polymers of calcium phosphate or gold doped hydroxyapatite (HAp), wherein in the second set of one or more metals zinc account for 3 to 6 wt% and calcium account for 1 to 3 wt%. The nano polymers of calcium phosphate comprise average size of 100 nm to 500nm and a flat plate shape self-assembled into a flower shape morphology. The nano polymers of gold doped HAp comprise average size of 50 nm to 100 nm and a flakes shape morphology.

[0030] In an exemplary embodiment, the implant biomaterial includes 92 wt % first set of one or more metals, 5 wt % second set of one or more metals and 3 wt % nano-polymers of calcium phosphate or gold doped hydroxyapatite (HAp). The specific wt % given for the first set of one or more metals, the second set of one or more metals and nano-polymer of calcium phosphate or gold doped hydroxyapatite (HAp) may manifest best properties to form the biocompatible material. The nano polymers of calcium phosphate comprise average size of 100 nm to 500nm and a flat plate shape self-assembled into a flower shape morphology. The nano polymers of gold doped HAp comprise average size of 50 nm to 100 nm and a flakes shape morphology.

[0031] The process provides biocompatible and biodegradable implants of nano-reinforced magnesium-based material having high intermetallic bond strength and uniform distribution in the lattice. The process improves overall strength of the implants while imparting lighter weight. Use of the implants made from the magnesium-based biocompatible material reduces the cost of health care system and suffering of patients by eliminating the requirement of repetition of surgery.

[0032] While specific language has been used to describe the disclosure, any limitations arising on account of the same are not intended. As would be apparent to a person skilled in the art, various working modifications may be made to the method in order to implement the inventive concept as taught herein.

[0033] The figures and the foregoing description give examples of embodiments. Those skilled in the art will appreciate that one or more of the described elements may well be combined into a single functional element. Alternatively, certain elements may be split into multiple functional elements. Elements from one embodiment may be added to another embodiment. For example, order of processes described herein may be changed and are not limited to the manner described herein. Moreover, the actions of any flow diagram need not be implemented in the order shown; nor do all of the acts need to be necessarily performed. Also, those acts that are not dependent on other acts may be performed in parallel with the other acts. The scope of embodiments is by no means limited by these specific examples.