Tuberculosis or better known as TB is an infectious disease that has a high mortality rate in the world. More than one million people in the world die from this disease. The World Health Organization (WHO) reported in 2016 that this disease had reached 10.4 million cases, and 34% of the total occurred in Southeast Asia, Indonesia was one of them.
This disease caused by the Mycobacterium tuberculosis bacteria which does not only attack the lungs as many people know. 5-10% of these cases occur in the bones and joints, especially in the spine, which eventually is often called bone tuberculosis.
Treatment is usually done using anti-tuberculosis drugs through infusion or injection. This method is considered ineffective because only half of the dose of the drug can reach the bone location.
For this reason, a new method is used to deliver the drug locally called bone filler. The main goal is to kill the bacteria that cause tuberculosis and also replace the part of the bone that is lost due to the bacteria.
Spinal surgery is needed to implement this method. The bone filler is not only used to fill empty parts of the bone but also as a medium to deliver anti-tuberculosis drugs on a regular basis in the affected part of the bacteria.
Bone fillers are generally made of ceramic materials, such as hydroxyapatite and organic materials such as gelatin to meet the bone constituents which also consist of both. These materials are biocompatible and are useful for bone repair because of this TB case.
Bone damage caused by tuberculosis leaves space in irregularly shaped bones. It is quite difficult to make bone fillers that have a shape fit with the bone damage. It is the basis for the emergence of a new method in the world of bone filler. The bone filler is in the form of a paste or suspension so that it can adjust its shape with bone damage that occurs.
This paste or suspension is called the Injectable Bone Substitute (IBS). By utilizing a material such as hydroxylpropylmethyl cellulose (HPMC) as a suspension forming agent, IBS can be made. Addition of anti-tuberculosis drugs, such as streptomycin, can be done to increase the ability of this IBS as a drug delivery agent.
Previous researches show that IBS is able to be made using ingredients such as hydroxyapatite, gelatin, HPMC, and streptomycin with variation of the ratio of hydroxyapatite and gelatin 40:60, 45:55, 50:50, 55:45, 60:40, 65:35, 70:30, and 75:25.
The result is a white paste that is ready to be injected. Evaluation of the characteristics possessed by IBS has also been carried out, including functional group test, injectability test, toxicity test, acidity test, antibacterial test, and drug release test. The best results are shown by samples with the composition of hydroxyapatite and gelatin in a ratio of 65:35.
The results showed that IBS was able to carry streptomycin which was shown from the functional group test results using Fourier Transform Infrared (FTIR) and also had a good injectability or ability to get out of injections up to almost 100%. Toxicity test using BHK-21 fibroblast cells showed that IBS is not toxic and even exceeds 100%, which means that cells can grow in this medium.
Antibacterial tests also showed that IBS was sensitive in killing bacteria with a zone of inhibition of more than 20 mm. The acidity test of IBS also shows good results by not changing the pH of body fluids, which is around 7.4. Even with the release of the drug, IBS can release 2.5% of the streptomycin it contains in 4 hours. It’s just that this IBS still takes a long time to harden on the appropriate media.
The results of this study indicate that IBS which is based on hydroxyapatite and gelatin with a ratio of 64:35 has characteristics that can support its application as bone filler candidate as it can deliver anti-tuberculosis drugs, streptomycin. (*)
Author: Alfian Pramudita Putra
Related article at:
https://www.hindawi.com/journals/ijbm/2019/7179243/
Dyah Hikmawati, Hendita N. Maulida, Alfian P. Putra, Aniek S. Budiatin, and Ardiyansyah Syahrom, “Synthesis and Characterization of Nanohydroxyapatite-Gelatin Composite with Streptomycin as Antituberculosis Injectable Bone Substitute,” International Journal of Biomaterials, vol. 2019, Article ID 7179243, 8 pages, 2019.
