Publication: Tüberküloz ilaçları ; rifampisin ve izoniazid'in arkeozomlardan salınımının incelenmesi
Abstract
Tüberküloz İlaçları; Rifampisin ve İzoniazid'in Arkeozomlardan Salınımının İncelenmesi Arkeozomlar Arkea bakterilerden ekstre edilen polar lipitlerden yapılan yeni jenerasyon lipozomlardır. Ester bağlı polar lipitlerden yapılan geleneksel ticari lipozomlara göre asidik ve bazik pH şartlarında ve yüksek sıcaklıklarda daha kararlıdırlar ve safra tuzlarına, fosfolipaz, oksidazların ve kimyasal hidrolazların etkilerine daha dayanıklıdırlar. Zorlu çevre koşullarına membran lipitlerini adapte edebildikleri için arkeozomlar vücudun ilaç, gen ve aşı gibi tedavilere karşı oluşturduğu fiziksel, biyolojik ve biyomedikal engellerin üstesinden gelebildikleri için son yıllarda ilaç taşıyıcı sistemlerinde önemli hale gelmişlerdir. Bu çalışmada Brown besiyerinde ürettiğimiz aşırı halofil Haloarcula 2TK2 suşunun polar eter lipitleri kloroform/ metanol çözeltisi ile ekstre edilmiş ve polar lipitlerin termal analizi diferansiyel taramalı kalorimetre (DSC) ile yapılmıştır. Çözücünün buharlaştırılmasından sonra hidrasyon yöntemi ile lipitlerden arkeozomlar elde edilmiştir. Arkeozomlara tüberküloz tedavisinde çok önemli tedavi ajanları olan Rifampisin (RIF) ve İzoniazid (INH) ayrı ayrı ve birlikte yüklenmiştir. Arkeozomların görüntüleri çevresel taramalı elektron mikroskobu ile alınmış ve zeta potansiyelleri ise Zeta Seizer cihazı ile ölçülmüştür. İlaçların bağlanma yüzdeleri ve yüklenme kapasiteleri hesaplanmış ve 24 saat boyunca salınımları in vitro ortamda 474 nm’de spektrofotometrik olarak izlenmiştir. Kolin klorit ve kolesterol (2:1) den elde edilen lipozomlara da aynı ilaçlar yüklenmiş ve arkeozomlar için yapılan işlemler tekrarlanmıştır. Çalışmamızın sonucunda Haloarcula 2TK2 suşunun polar lipidlerinin 20-120oC’de belirgin bir faz geçişi olmadığı saptandı. Arkeozomların ve lipozomların yüzeylerinin eksi yükle kaplandıkları gözlendi. RIF ve INH’nin arkeozom ve lipozomlara bağlanma yüzdeleri ve bağlanma kapasiteleri incelendiğinde RIF’ın bağlanma yüzdelerinin ve bağlanma kapasitesinin INH’den daha fazla, her iki ilacın arkeozomlara bağlanmasının lipozomlara göre daha yüksek olduğu saptanmıştır. RIF ve INH’nin birlikte yüklendikleri lipozom ve arkeazomların bağlanma yüzdeleri ve kapasiteleri kıyaslandığında lipozomlar için daha iyi sonuçlar alınmıştır. İlaçların salınımları incelendiğinde RIF yüklenen arkeozomun salınım değerinin diğer salınım sonuçlarına göre ve lipozomlara göre daha yüksek olduğu belirlendi. INH salınım sonuçları incelendiğinde ise arada çok fark olmamasına rağmen lipozomlardaki salınımının arkeozomlara göre yüksek olduğu gözlendi. RIF ve INH’nin birlikte yüklendikleri salınım sonuçları incelendiğinde arkeozomlarda RIF’ın, lipozomlarda ise INH salınım değerlerinin yüksek olduğu belirlendi. Sonuç olarak Haloarcula 2TK2 suşundan hazırladığımız arkeazomların RIF ve INH’nin yüklenmesi, kararlı ve kontrollü salınımı için uygun olduğunu ve ilaç sanayinde kullanılabileceğini düşünüyoruz.
Release Studies of Antituberculosis Drugs; Rifampicin and Isoniasid from Archeaeasomes Archaeosomes which are made from polar ether lipids of Archaea bacteria are a novel generation of liposomes. They resist to acidic or alkaline pH, bile salts and high temperatures. Archaeosomes are more tolerant to chemical and enzymatic hydrolysis, phospholipases, oxidation, when compared to conventional liposomes. The ability of Archaea to adapt their membrane lipid compositions to extreme environments has brought in archeasomes into consideration for the development of drug delivery systems overcoming the physical, biological blockades that the body exhibits against gene, drug and vaccine therapies. In the present study polar lipids of Haloarcula 2TK2 strain grown in Brown agar medium were extracted by chloroform/ methanol solvent system. The thermal analysis of polar lipids was performed by using differential scanning calorimeter (DSC). Archeasomes were prepared by dried lipid film hydration method. Rifampicin (RIF) and Isoniasid (INH) which are conventional drugs in tuberculosis medication were loaded separately and together. Images of the archaeosomes were taken by environmental scanning electron microscope. Zeta potentials were measured by photon correlation spectroscopy (PCS). Encapsulation efficiency and loading capacities of the drugs were determined and in vitro drug releases were monitored spectrophotometrically. The same drugs were loaded to the liposomes prepared from cholin chloride and cholesterol (2:1). The same procedures were applied for liposomes. Thermal analysis of polar lipids of Haloarcula 2TK2 strain revealed no well-defined phase transition in the temperature range of 20 to 1200C. The surface of the drug loaded archaeosomes and liposomes was negatively charged. When the encapsulation efficiency and loading capacities of the drugs were compared, RIF had higher binding efficiency and loading capacity and release values for archaeosomes than INH. Both of the drugs had greater affinity for archeasomes than for liposomes. However, when RIF and INH were loaded together to archeasomes and liposomes, binding efficiency, loading capacity and release values for liposomes were found high. RIF and INH could be successfully entrapped in archaeosomes with reasonable drug-loading and desired vesicle specific characters. It was concluded that archaeosomes prepared from extremely halophilic archaeon were compatible with the liposomes for the development of stable and sustained release of antitubercilosis drugs. Therefore RIF and INH-loaded archaeosomes are demonstrated for future use in pharmaceutical industry.
Release Studies of Antituberculosis Drugs; Rifampicin and Isoniasid from Archeaeasomes Archaeosomes which are made from polar ether lipids of Archaea bacteria are a novel generation of liposomes. They resist to acidic or alkaline pH, bile salts and high temperatures. Archaeosomes are more tolerant to chemical and enzymatic hydrolysis, phospholipases, oxidation, when compared to conventional liposomes. The ability of Archaea to adapt their membrane lipid compositions to extreme environments has brought in archeasomes into consideration for the development of drug delivery systems overcoming the physical, biological blockades that the body exhibits against gene, drug and vaccine therapies. In the present study polar lipids of Haloarcula 2TK2 strain grown in Brown agar medium were extracted by chloroform/ methanol solvent system. The thermal analysis of polar lipids was performed by using differential scanning calorimeter (DSC). Archeasomes were prepared by dried lipid film hydration method. Rifampicin (RIF) and Isoniasid (INH) which are conventional drugs in tuberculosis medication were loaded separately and together. Images of the archaeosomes were taken by environmental scanning electron microscope. Zeta potentials were measured by photon correlation spectroscopy (PCS). Encapsulation efficiency and loading capacities of the drugs were determined and in vitro drug releases were monitored spectrophotometrically. The same drugs were loaded to the liposomes prepared from cholin chloride and cholesterol (2:1). The same procedures were applied for liposomes. Thermal analysis of polar lipids of Haloarcula 2TK2 strain revealed no well-defined phase transition in the temperature range of 20 to 1200C. The surface of the drug loaded archaeosomes and liposomes was negatively charged. When the encapsulation efficiency and loading capacities of the drugs were compared, RIF had higher binding efficiency and loading capacity and release values for archaeosomes than INH. Both of the drugs had greater affinity for archeasomes than for liposomes. However, when RIF and INH were loaded together to archeasomes and liposomes, binding efficiency, loading capacity and release values for liposomes were found high. RIF and INH could be successfully entrapped in archaeosomes with reasonable drug-loading and desired vesicle specific characters. It was concluded that archaeosomes prepared from extremely halophilic archaeon were compatible with the liposomes for the development of stable and sustained release of antitubercilosis drugs. Therefore RIF and INH-loaded archaeosomes are demonstrated for future use in pharmaceutical industry.