Electrodeposition of titanium on stainless steel(316LSS) for biomedical applications

Project Title

Electrodeposition of titanium on stainless steel(316LSS) for biomedical applications

Project Area of Specialization Biomedical EngineeringProject Summary

Bone fractures are a public health issue around the world and pose a serious economic burden especially in people with osteoporosis. Fractures can lead to work absence, decreased productivity, disability, impaired quality of life, health loss, and high health-care costs and are a major burden to individuals, families, societies, and health-care systems. According to a survey [1] the total number of facture cases in the past 29 years has increased from 62.4% to 68.0%. Orthopedic implants are used to replace damaged bones or joints in case of injuries, arthritis, and fractures. As the population ages and more people get joint substitution, the costs of importing implants are likely to keep rising. It is estimated that the cost of a hip implant in Pakistan varies between $4000 to $10000 with an average hospital stay of 7-10 days. The global orthopedic implants market accounted for $47,261 million in 2021, and is anticipated to reach at $74,796 million by 2027. [2] Titanium a frequently used material for making long lasting orthopedic implants due its high strength, biocompatibility, and good corrosion resistance. However, it is quite expensive material. Most people cannot afford that expensive implant. Implants made of surgical grade stainless steel (316LSS) is nowadays dominant in biomedical industry, but only for temporary orthopedic implants. It exhibits excellent material properties, but it lacks biocompatibility and resistance to corrosion. [3] Therefore, a biocompatible coating over 316LSS is inevitable for making permanent biomedical implants. We use Electrophoretic deposition (EPD) technique [4], which is a technique for organic and inorganic material deposition. Among existing electrochemical approaches for coating biomaterials, EPD can be positively considered as one of the most promising methods. References Wu D. A.-M. (2021). Global, regional, and national burden of bone fractures in. The Lancet Healthy Longetivity, 13 Orthopedic Implants Market Drivers & Growth Opportunity Analysis Report 2021-2030, Market Watch,  https://www.marketwatch.com/press-release/orthopedic-implants-market-drivers-growth-opportunity-analysis-report-2021-2030-2022-03-04 Aroussi D, et al. "A comparative study of 316L stainless steel and a titanium alloy in an aggressive biological medium" Engineering, Technology & Applied Science Research 9.6 (2019) Saleem O, et al. “Fabrication and Characterization of Ag?Sr-Substituted Hydroxyapatite/Chitosan Coatings Deposited via Electrophoretic Deposition: A Design of Experim ent Study”,ACS Omega  2020

Bone fractures are a public health issue around the world and pose a serious economic burden especially in people with osteoporosis. Fractures can lead to work absence, decreased productivity, disability, impaired quality of life, health loss, and high health-care costs and are a major burden to individuals, families, societies, and health-care systems. According to a survey [1] the total number of facture cases in the past 29 years has increased from 62.4% to 68.0%.

Orthopedic implants are used to replace damaged bones or joints in case of injuries, arthritis, and fractures. As the population ages and more people get joint substitution, the costs of importing implants are likely to keep rising. It is estimated that the cost of a hip implant in Pakistan varies between $4000 to $10000 with an average hospital stay of 7-10 days. The global orthopedic implants market accounted for $47,261 million in 2021, and is anticipated to reach at $74,796 million by 2027. [2]

Titanium a frequently used material for making long lasting orthopedic implants due its high strength, biocompatibility, and good corrosion resistance. However, it is quite expensive material. Most people cannot afford that expensive implant. Implants made of surgical grade stainless steel (316LSS) is nowadays dominant in biomedical industry, but only for temporary orthopedic implants. It exhibits excellent material properties, but it lacks biocompatibility and resistance to corrosion. [3] Therefore, a biocompatible coating over 316LSS is inevitable for making permanent biomedical implants.

We use Electrophoretic deposition (EPD) technique [4], which is a technique for organic and inorganic material deposition. Among existing electrochemical approaches for coating biomaterials, EPD can be positively considered as one of the most promising methods.

References

1. Wu D. A.-M. (2021). Global, regional, and national burden of bone fractures in. The Lancet Healthy Longetivity, 13
2. Orthopedic Implants Market Drivers & Growth Opportunity Analysis Report 2021-2030, Market Watch,  https://www.marketwatch.com/press-release/orthopedic-implants-market-drivers-growth-opportunity-analysis-report-2021-2030-2022-03-04
3. Aroussi D, et al. "A comparative study of 316L stainless steel and a titanium alloy in an aggressive biological medium" Engineering, Technology & Applied Science Research 9.6 (2019)
4. Saleem O, et al. “Fabrication and Characterization of Ag?Sr-Substituted Hydroxyapatite/Chitosan Coatings Deposited via Electrophoretic Deposition: A Design of Experim ent Study”,ACS Omega  2020

Project Objectives

The following are the objectives to be achieved.

1. To design 3D implant using 3D modeling® software
2. To prototype the implant
3. To coat Titanium on a stainless-steel (316LSS) orthopedic implant using Electrophoretic deposition technique
4.  To investigate surface morphology, strength and biocompatibility of the implant

Project Implementation Method

As the first step, we plan to design a model of 3D implant (ball and socket joint) made of stainless steel 316L by using a 3D Modeling Software such as Fusion360. Next, we fabricate its prototype using CNC machine. Later, we initiate the process of electrodeposition. For this, we need to assemble the laboratory setup for electrophoretic deposition shown in Figure 1 taking the following steps: Preparing an electrolyte solution comprising Titanium dioxide (TiO2) and Hydrochloric acid (HCL) The pretreatment of the surfaces of the source and target implant to ensure a uniform coating Placing the electrolyte in a appropriately sized container Placing titanium and the 316LSS on the correct electrodes Connecting the electrodes to the right polarities of the battery Applying the right voltage for the right duration to effectuate the process of electrophoretic deposition. After the successful process of electrophoretic deposition, the implant is heated and sintered at the right temperatures for right duration. Characterization tests must be performed to ascertain the presence of the expected properties in the resulting implant. These include SEM for investigating surface morphology, material strength tests, and biocompatibility tests using Simulated Bodily Fluids.                        Figure 1: Laboratory setup for electrophoretic deposition

As the first step, we plan to design a model of 3D implant (ball and socket joint) made of stainless steel 316L by using a 3D Modeling Software such as Fusion360.

Next, we fabricate its prototype using CNC machine. Later, we initiate the process of electrodeposition. For this, we need to assemble the laboratory setup for electrophoretic deposition shown in Figure 1 taking the following steps:

1. Preparing an electrolyte solution comprising Titanium dioxide (TiO2) and Hydrochloric acid (HCL)
2. The pretreatment of the surfaces of the source and target implant to ensure a uniform coating
3. Placing the electrolyte in a appropriately sized container
4. Placing titanium and the 316LSS on the correct electrodes
5. Connecting the electrodes to the right polarities of the battery
6. Applying the right voltage for the right duration to effectuate the process of electrophoretic deposition.

After the successful process of electrophoretic deposition, the implant is heated and sintered at the right temperatures for right duration.

Characterization tests must be performed to ascertain the presence of the expected properties in the resulting implant. These include SEM for investigating surface morphology, material strength tests, and biocompatibility tests using Simulated Bodily Fluids.

                       Figure 1: Laboratory setup for electrophoretic deposition

Benefits of the Project

Some of the benefits that can be achieved from the implementation of this project are:

1. Increased strength and durability of biomedical implants
2. Increased biocompatibility
3. Improved quality of life and lessened economic repercussions
4. Decreased cost of implant
5. Development of high-tech skills for biomedical implant design

316L stainless steel is known for its good resistance, high strength, low cost but it lacks biocompatibility and there is always a concern about their corrosion resistance in a physiological medium. The effects of surface treatment and metallic coating on the corrosion behavior and biocompatibility of surgical 316L stainless steel implants were evaluated in. The experimental results indicated that coating and surface treatment of the stainless steel improved its biocompatibility.

Technical Details of Final Deliverable

At the end of our project, we expect to have:

1. A 3D model of a hip implant designed in a 3D modeling software, e.g., Fusion360.
2. Laboratory set up for electrodeposition comprising a case with proper electrolyte solution, electrodes, connectors, and power supply
3. 1A complete in all respects hip implant made of 316L stainless steel with a layer of titanium uniformly deposited over it. The implant weighs around 210 grams. Figure 2 shows the model of the hip implant designed using Fusion360.

                     Figure 2: 3D model of a hip implant

Final Deliverable of the Project Hardware SystemCore Industry MedicalOther Industries Others Core Technology OthersOther Technologies OthersSustainable Development Goals Good Health and Well-Being for PeopleRequired Resources

As the first step, we plan to design a model of 3D implant (ball and socket joint) made of stainless steel 316L by using a 3D Modeling Software such as Fusion360. Next, we fabricate its prototype using CNC machine. Later, we initiate the process of electrodeposition. For this, we need to assemble the laboratory setup for electrophoretic deposition shown in Figure 1 taking the following steps: Preparing an electrolyte solution comprising Titanium dioxide (TiO2) and Hydrochloric acid (HCL) The pretreatment of the surfaces of the source and target implant to ensure a uniform coating Placing the electrolyte in a appropriately sized container Placing titanium and the 316LSS on the correct electrodes Connecting the electrodes to the right polarities of the battery Applying the right voltage for the right duration to effectuate the process of electrophoretic deposition. After the successful process of electrophoretic deposition, the implant is heated and sintered at the right temperatures for right duration. Characterization tests must be performed to ascertain the presence of the expected properties in the resulting implant. These include SEM for investigating surface morphology, material strength tests, and biocompatibility tests using Simulated Bodily Fluids.                        Figure 1: Laboratory setup for electrophoretic deposition