Sains Malaysiana 44(9)(2015): 1351–1356

Pore Interconnectivity Analysis of Porous Three Dimensional Scaffolds of Poly (3-Hydroxybutyric Acid) (PHB) and Poly(3-Hydroxybutyric-co-3-Hydroxyvaleric Acid) (PHBV) Through Non-Invasive Color Staining Method

(Analisis Kebolehjaringan Liang bagi Struktur Perancah Tiga Dimensi Poly(3-Hydroxybutyric Acid) (PHB) dan Poly(3-Hydroxybutyric-co-3-Hydroxyvaleric Acid) (PHBV) melalui Kaedah Pengotoran Warna tidak Invasi)

SAIFUL IRWAN ZUBAIRI¹, ATHANASIOS MANTALARIS²* & ALEXANDER BISMARCK²

¹School of Chemical Sciences & Food Technology, Faculty of Science & Technology

Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor Darul Ehsan, Malaysia

²Department of Chemical Engineering, Imperial College London, South Kensington Campus, London SW7 2AZ, United Kingdom

Received: 14 November 2013/Accepted: 3 June 2015

ABSTRACT

Polyhydroxyalkanoates (PHAs) has been investigated for more than eighty years. Ever since then, the scientists are kept on synthesizing and developing new polymers and application to suit human interests nowadays. The resourcefulness of PHAs has made them a good candidates for the study of their potential in a variety of areas from biomedical/medical fields to food, packaging, textile and household material. In medical field (specifically in tissue engineering application), producing a biocompatible 3-D scaffold with adaptable physical properties are essential. However, to the best of our knowledge, scaffolds from PHB and PHBV with thickness greater than 1 mm have not been produced yet. In this work, PHB and PHBV porous 3-D scaffolds with an improved thickness greater than 4 mm was fabricated using conventional method of solvent-casting particulate-leaching (SCPL). A preliminary assessment on the improved thickness 3-D scaffolds was carried out to examine its pore interconnectivity by using non-invasive color staining method. The vertical cross sections image of the stained scaffolds was analyzed by image analyzer software. This technique was considered simple, fast and cost effective method prior to the usage of super accurate analytical instruments (micro-computed tomography). The results showed that over 80% of the pores have been interconnected with the adjacent pores. Moreover, there was a good correlation between the predicted pore interconnectivity and porosity. These results indicated how well a simple technique can do by giving an overview of the internal morphology of a porous 3-D structure material.

Keywords: Color staining; PHBV; PHB; pore interconnectivity; 3-D scaffold

ABSTRAK

Polyhydroxyalkanoates (PHAs) telah dikaji lebih dari 80 tahun yang lalu. Semenjak dari itu, para saintis sentiasa mensintesis dan membangunkan polimer dan aplikasi baru bagi kemudahan dan penggunaan manusia sekarang. Kepelbagaian penggunaan PHAs telah menjadikan bahan tersebut sebagai calon yang sesuai dalam mengkaji pelbagai potensi daripada bidang bioperubatan/perubatan ke makanan, pembungkusan, tekstil dan bahan penggunaan di rumah. Dalam bidang perubatan (terutama sekali dalam aplikasi kejuruteraan tisu, penghasilan struktur perancah 3-D yang bioserasi dengan pengadaptasian ciri fizikal adalah penting. Tetapi, sehingga kini, masih tiada lagi struktur perancah daripada PHB dan PHBV dengan ketebalan melebihi 1 mm dapat dihasilkan. Dalam kajian ini, struktur perancah 3-D PHB dan PHBV dengan penambahbaikan ketebalan melebihi 4 mm telah dapat difabrikasi menggunakan kaedah konvensional pelarut-pembentuk larut serap partikulat (SCPL). Penilaian awalan terhadap struktur perancah 3-D telah dijalankan bagi menilai kebolehjaringan liang menggunakan kaedah pengotoran warna tidak invasi. Imej keratan rentas bagi struktur perancah yang dikotorkan dianalisis menggunakan perisian penganalisis imej. Kaedah ini dianggap mudah, pantas dan kos efektif sebelum penggunaan peralatan analitikal canggih (seperti tomografi mikro berkomputer). Keputusan kajian menunjukkan bahawa lebih 80% liang telah dibolehjaringkan dengan liang-liang yang berdekatan. Sebagai tambahan, terdapat kolerasi yang baik antara jangkaan kebolehjaringan liang dan keliangan. Keputusan ini memberi indikasi bahawa ia merupakan teknik yang mudah dalam memberikan gambaran awal tentang morfologi dalaman struktur bahan perancah 3-D.

Kata kunci: Kebolehjaringan liang; pengotoran warna; PHBV; PHB; Struktur 3-D

REFERENCES

Cheng, S., Chen, G.Q., Leski, M., Zou, B., Wang, Y. & Wu, Q. 2006. The effect of d,l-β-hydroxybutyric acid on cell death and proliferation in L929 cells. Biomaterials 27(20): 3758-3765.

Chung, C.W., Kim, H.W., Kim, Y.B. & Rhee, Y.H. 2003. Poly(ethylene glycol)-grafted poly(3-hydroxyundecenoate) networks for enhanced blood compatibility. International Journal of Biological Macromolecules 32(1-2): 17-22.

Freeman, M. 2005. The Digital SLR Handbook. Lewes: ILEX.

Gassner, F. & Owen, A.J. 1996. Some properties of poly(3- hydroxybutyrate)-poly(3-hydroxyvalerate) blends. Polymer International 39(3): 215-219.

Hazaree, C., Wang, K., Ceylan, H. & Gopalakrishnan, K. 2011. Capillary transport in RCC: water-to-cement ratio, strength, and freeze-thaw resistance. J. Mater. Civ. Eng. 23(8): 1181- 1191.

Lu, J.X., Flautre, B., Anselme, K., Hardouin, P., Gallur, A., Descamps, M. & Thierry, B. 1999. Role of interconnections in porous bioceramics on bone recolonization in vitro and in vivo. Journal of Materials Science: Materials in Medicine 10(2): 111-120.

Lianlai, Z., Xianmo, D., Shujie, Z. & Zhitang, H. 1997. Biodegradable polymer blends of poly(3-hydroxybutyrate) and poly(-D,L-lactide)-co-poly(ethylene glycol). Journal of Applied Polymer Science 65(10): 1849-1856.

Pouton, C.W. & Akhtar, S. 1996. Biosynthetic polyhydroxyalkanoates and their potential in drug delivery. Advanced Drug Delivery Reviews 18(2): 133-162.

Qu, X.H., Wu, Q., Liang, J., Zou, B. & Chen, G.Q. 2006. Effect of 3-hydroxyhexanoate content in poly(3-hydroxybutyrate-co- 3-hydroxyhexanoate) on in vitro growth and differentiation of smooth muscle cells. Biomaterials 27(15): 2944-2950.

Shi, H.L., Joost, R.D., Wijn, P.L. & Klaas, D.G. 2002. Synthesis of macroporous hydroxyapatite scaffolds for bone tissue engineering. Journal of Biomedical Materials Research 61(1): 109-120.

Siracusa, V., Rocculi, P., Romani, S. & Rosa, M.D. 2008. Biodegradable polymers for food packaging: A review. Trends in Food Science & Technology 19(12): 634-643.

Tabesh, H., Amoabediny, G., Nik, N.S., Heydari, M., Yosefifard, M., Siadat, S.O.R. & Mottaghy, K. 2009. The role of biodegradable engineered scaffolds seeded with Schwann cells for spinal cord regeneration. Neurochemistry International 54(2): 73-83.

Williams, S.F., Martin, D.P., Horowitz, D.M. & Peoples, O.P. 1999. PHA applications: addressing the price performance issue: I. Tissue engineering. International Journal of Biological Macromolecules 25(1-3): 111-121.

*Corresponding author; email: a.mantalaris@imperial.ac.uk