Poly(lactic-co-glycolic acid) based drug delivery devices for tissue engineering and regenerative medicine

Poli(D,L-laktid-ko-glikolid) (PLGA) kontrollü salım (KS) uygulamalarında terapötik ilaçları enkapsüle eden nano/mikropartiküllerin geliştirilmesinde sıklıkla kullanılan biyolojik olarak parçalanma özelliğine sahip bir polimerdir. PLGA ile hazırlanmış ilaç sistemlerinin konvansiyonel sistemlere göre çok sayıda avantajı bulunmaktadır. Bu avantajlardan biri, ilaçların uzatılmış salım özelliklerinin günler, haftalar veya aylarca devam edebilmesidir. PLGAnın yaygın kullanımının diğer sebepleri ise biyolojik olarak parçalanabilir olması, biyolojik olarak geçimli olması ve FDA (Gıda ve İlaç İdaresi) tarafından onaylanmış olmasıdır. Kanser tedavisinde kullanılan ilaçlar, analjezikler, antibiyotikler gibi çeşitli aktif farmasötik ajanların yanısıra protein, peptid, gen, aşı, antijen, insan büyüme faktörleri, vasküler endotelial büyüme faktörleri gibi makromoleküler yapıdaki çeşitli ilaçlar PLGA veya PLGA ile hazırlanmış ilaç sistemleri içerisine başarılı bir şekilde yüklenebilmektedir. Sonuç olarak bu sistemler genel olarak ilaçların hedeflendirilmesinde (hücresel veya doku temelinde), ayrıca lokal etkilerinin de fayda sağlayacağı sistemlerde kullanılmaktadır. Biyoyararlanımı artırırlar, ilaç salımını uzatırlar veya sistemik etki amacıyla ilaçların çözünmesini sağlarlar. Gelecekte yapılacak araştırma ve geliştirme çalışmalarında PLGA veya PLGA ile hazırlanmış ilaç sistemleri çeşitli avantajlarından dolayı ilgi çekici bir alandır. Bu derlemede PLGAnın fizikokimyasal ve biyolojik olarak parçalanma özelliklerinin yanısıra doku mühendisliği ve rejeneratif tıp için PLGA ile hazırlanmış ilaç sistemleri sunulmaktadır.

Doku mühendisliği ve rejeneratif tıpta kullanılan poli (laktik-ko-glikolik asit) ile hazırlanmış ilaç sistemleri

Poly(D,L-lactide-co-glycolide) (PLGA) is the most frequently used biodegradable polymer for developing nano/microparticles encapsulating therapeutic drugs in controlled release (CR) applications. PLGA based drug delivery devices have several advantages over the conventional devices. One of the advantage is the extended release rates of drugs up to days, weeks or months. Other reasons for the widespread use of PLGA are its biodegradability, its biocompatibility, and the fact that PLGA has been approved by FDA (Food and Drug Administration). Numerous active pharmaceutical ingredients such as anti-cancer drugs, analgesics, antibiotics and macromolecular drugs such as proteins, peptides, genes, vaccines, antigens, human growth factors, vascular endothelial growth factors etc., are successfully incorporated into PLGA or PLGA based drug delivery devices. As a result, these systems in general can be used to provide targeted (cellular or tissue) delivery of drugs, which localized effect represents also an important benefit. They improve bioavailability, sustain release of drugs or solubilize drugs for systemic delivery. Drug delivery using PLGA or PLGA based polymers is an attractive area with various opportunities for further research and developmental work. In this review, physicochemical and biodegradable properties of PLGA and PLGA based drug delivery devices for tissue engineering and regenerative medicine will be presented.

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