Sains Malaysiana 38(5)(2009): 785–791

Pengembungan Hidrogel Selulosa Bakteria-Asid Akrilik: Sensitiviti

Terhadap Rangsangan Luar

(Swelling of Bacterial Cellulose-Acrylic Acid Hydrogels: Sensitivity Towards External Stimuli)

Nadia Halib¹, Mohd Cairul Iqbal Mohd Amin²*, Ishak Ahmad³,

Zulkifli Mohamed Hashim¹ & Noriah Jamal¹

¹Bahagian Teknologi Perubatan, Agensi Nuklear Malaysia

Bangi, 43000 Kajang, Selangor, Malaysia

²Fakulti Farmasi, Universiti Kebangsaan Malaysia

Jalan Raja Muda Abdul Aziz, 50300 Kuala Lumpur, Malaysia

³Pusat Pengajian Sains Kimia dan Teknologi Makanan

Fakulti Sains dan Teknologi, Universiti Kebangsaan Malaysia

43600 UKM, Bangi, Selangor, Malaysia

Diserahkan: 15 Julai 2008 / Diterima: 14 Januari 2009

ABSTRAK

Kajian ini telah menilai kesan pelbagai faktor persekitaran terhadap darjah pengembungan hidrogel selulosa bakteria-asid akrilik. Campuran akues selulosa bakteria-asid akrilik (4:1) telah disediakan dan didedahkan dengan irradiasi alur elektron pada 35 kGy dan 50 kGy. Kadar pengembungan di bawah pengaruh pH, suhu dan kekuatan ionik telah dikaji dari 1 hingga 24 jam. Darjah pengembungan hidrogel bergantung kepada dos irradiasi yang diberi: hidrogel yang telah disintesis pada 50 kGy mempunyai darjah pengembungan yang lebih tinggi secara signifikan (p<0.0001) dalam metanol (619%) berbanding air suling (510%) pada suhu bilik selepas 24 jam. Kekuatan ionik persekitaran mempengaruhi dengan peningkatan kepekatan natrium klorida menurunkan darjah pengembungan. Hidrogel juga peka terhadap perubahan pH: pengembungan meningkat dengan peningkatan pH dan nilai optimal dicapai pada pH 7. Selain itu pengembungan juga meningkat dengan peningkatan suhu dari 25¡C sehingga 50¡C. Kesimpulannya, keupayaan hidrogel selulosa bakteria-asid akrilik dedahan irradiasi elektron bertindak balas terhadap pelbagai rangsangan faktor persekitaran, menjadikan ia satu bahan yang boleh dibangunkan sebagai sistem penyampaian aktif untuk dadah, protein dan hormon.

Kata kunci: Faktor luaran; hidrogel; selulosa bakteria; sistem penyampaian

ABSTRACT

This study evaluated various environmental factors affecting the swelling degree of bacterial cellulose-acrylic acid hydrogels. Aqueous bacterial cellulose-acrylic acid (4:1) mixtures were prepared and subjected to electron beam irradiation at 30 and 50 kGy. Swelling rate under influenced of pH, temperature and ionic strength was investigated from 1 to 24 hours. Swelling degree of hydrogels was dependent on irradiation dose: those synthesized at 50 kGy exhibited significant higher swelling degree (p<0.0001) in methanol (619%) compared to water (510%) at room temperature after 24 hours. External ionic strength affected swelling, i.e, elevation in sodium chloride concentration decreased swelling degree. Hydrogels were also sensitive to pH: swelling increased with increasing pH and was optimal at pH 7. Swelling also increased with increasing temperature from 25¡C to 50¡C. In conclusion, the ability of electron irradiated bacterial cellulose-acrylic acid hydrogels to respond to various external environment make it a material to be developed as an active delivery system for drugs, proteins and hormones.

Keywords: Bacterial cellulose; delivery systems; external stimuli; hydrogels

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*Pengarang untuk surat-menyurat; email: mciamin@pharmacy.ukm.my