Timalol, hipertansiyon, kalp krizi, anjin pektoris, migren gibi rahatsızlıkların tedavisinde ve ayrıca miyokard enfarktüsünün ikincil önlenmesinde ağızdan tablet şeklinde kullanılan bir ilaçtır. Aynı zamanda, yüksek göz içi basıncını düşürme amacıyla da göz damlası şeklinde kullanılmaktadır. Seçici (Selektif) bir ilaç olmadığından ötürü bazı yan etkileri vardır. Olası yan etkileri arasında kardiyak aritmiler ve şiddetli bronkospazm vardır. Ayrıca, Raynaud sendromu’nun kötüleşmesi, iktidarsızlık, bayılma, konjestif kalp yetmezliği, depresyon ve kafa karışıklığı gibi sorunlara yol açabilir. Bu ilacın yan etkilerinin azaltılması için Timolol’ un Salımını daha düzenli olarak sağlayabilecek bir ilaç taşıyıcısı (drug carrier) üzerinde çalışmalar yapılmaktadır.

Aşağıda İngilizce detayları da verilen bu çalışmada;

Montmorillonitin Timolol’a eklenmesi (intercalation) sağlanmış, In vitro (laboratuvar) ortamında yapılan gözlemlerde Gastrik ve Bağırsak Sıvısı ortamlarında yapılan simülasyonlarda, Timolol’ün Montmorillonit ile birlikte düzenli ve kontrollü ilaç salımı (Drug Release) sağladığı gözlemlenmiştir

Montmorillonite As A Drug Delivery System: Intercalation And In Vitro Release Of Timolol Maleate
Joshi GV, Kevadiya BD, Patel HA, Bajaj HC, Jasra RV.
Discipline of Inorganic Materials and Catalysis, Central Salt and Marine Chemicals Research Institute, Council of Scientific and Industrial Research, Gijubhai Badheka Marg, Bhavnagar, Gujarat, India.
PMID: 19446759 [PUBMED – indexed for MEDLINE] Int J Pharm. 2009 Jun 5;374(1-2):53-7.
Discipline of Inorganic Materials and Catalysis, Central Salt and Marine Chemicals Research Institute, Council of Scientific and Industrial Research, Gijubhai Badheka Marg, Bhavnagar, Gujarat, India.
Abstract: The need for safe, therapeutically effective, and patient-compliant drug delivery systems continuously leads researchers to design novel tools and strategies. Clay minerals play a very crucial role in modulating drug delivery. This work examines the advantageous effect of clay mineral as drug carrier for timolol maleate (TM), a nonselective beta-adrenergic blocking agent. The intercalation of TM into the interlayer of montmorillonite (MMT) at different pH and initial concentration is demonstrated. MMT-TM hybrid was characterized by X-ray diffraction (XRD), Fourier transformed infrared (FT-IR), and thermal analysis (TG-DTA). TM was successfully intercalated into the interlayer of MMT, and in vitro release properties of the intercalated TM have been investigated in simulated gastric fluid (pH 1.2) and simulated intestinal fluid (pH 7.4) at 37+/-0.5 degrees C. Controlled release of TM from MMT-TM hybrid has been observed during in vitro release experiments.
Conclusion: In summary, we have shown the intercalation of TM into MMT and in vitro release of TM from MMT–TM hybrid. The intercalation of TM into MMT was rapid process and equilibrium was attained within 1 h. The maximum amount of TM intercalated into MMT is 217 mg/g MMT within 1 h at pH 5.7 and 30◦ C. Intercalation of TM into MMT depends on the pH of the interaction medium. XRD patterns of hybrid material shows an increase in the d-spacing, conforming the intercalation of TM into the interlayer of MMT. TGDTA of MMT–TM shows a sharp weight loss at about 200◦ C due to decomposition of exchanged TM. In vitro release study showed that about 43 and 48% of TM was released from MMT–TM hybrid in simulated gastric fluid (pH 1.2) and intestinal fluid (pH 7.4), respectively. These studies indicate that MMT can be used as the sustained release carrier of TM in oral administration.