Film Coating

A B S T R A C T Extended drug delivery offers numerous benefits compared to immediate release dosage form. Membrane coating of immediate release dosage form is an effective means of producing an extended drug delivery system. Polymers when coated alone, have limited ability to form the rate controlling membrane with good mechanical properties. Addition of plasticizer is vital to the formation of a robust rate-controlling membrane. Plasticizers have the ability to interact with polymer chains, and provide desired flexibility, shock resistance, and smoothness to resultant system. In addition to the plasticizing effect they also play an important role in modulating drug release profiles. Selection of a plasticizer is critical for the stability of dosage form, the processing as well as in vivo performance. In this review article, various theoretical and practical methods for plasticizer selection have been discussed in detail and supported with the mechanism of action. Applications, where plasticizers are required in higher quantities, like dry coating, compression of coated pellets or required to form membrane to imbibe water i.e. osmotic drug delivery system are also discussed. Importantly, the selection criteria and quantity of plasticizer should also be considered from the regulatory perspective for an efficient drug product approval process.

There has been an increasing interest in the use of natural materials as drug delivery vehicles due to their biodegradability, biocompatibility and ready availability. These properties make bacterial cellulose (BC), from nata de coco, a promising biopolymer for drug delivery applications. The aim of this study was to investigate the film-coating and drug release properties of this biopolymer. Physicochemical, morphological and thermal properties of BC films were studied. Model tablets were film coated with BC, using a spray coating technique, and in vitro drug release studies of these tablets were investigated. It was found that BC exhibited excellent ability to form soft, flexible and foldable films without the addition of any plasticizer. They were comparable to Aquacoat ECD (with plasticizer) in tensile strength, percentage elongation and elasticity modulus. Differential scanning calorimetry (DSC) BC showed a high Tg value indicating thermally stability of films. These results su...

This study evaluated the physiological quality and quantified the efficiency of polymer in reducing the loss of phytosanitary products by leaching from soybean seeds of different diameters and in different treatments. Two lots of seed and two types of treatments were tested: polymers associated with seed treatment, and polymer application in layers after the seed treatment. For that, the following treatments were analyzed: Control= no seed treatment; Treat+pol= seed treatment + polymers in the mix; Treat/pol= seed treatment + polymers applied in layers; Treat= seed treatment. To evaluate seed treatment retention by the polymers, extraction equipment was employed and leaching of the active ingredient thiamethoxam was quantified. Evaluation of physical quality was conducted with tests of germination rate, first count, emergence rate, accelerated aging, seedling length, seedling dry mass and moisture content. Polymer application associated with seed treatment was efficient in reducing losses by leaching, reducing product loss by 20%. No significant differences in retention and physiological quality were found when different methods for polymer application were compared. Bigger seeds presented greater vigor, but the germination rate was unaffected.

This study evaluated the physiological quality and quantified the efficiency of polymer in reducing the loss of phytosanitary products by leaching from soybean seeds of different diameters and in different treatments. Two lots of seed and two types of treatments were tested: polymers associated with seed treatment, and polymer application in layers after the seed treatment. For that, the following treatments were analyzed: Control= no seed treatment; Treat+pol= seed treatment + polymers in the mix; Treat/pol= seed treatment + polymers applied in layers; Treat= seed treatment. To evaluate seed treatment retention by the polymers, extraction equipment was employed and leaching of the active ingredient thiamethoxam was quantified. Evaluation of physical quality was conducted with tests of germination rate, first count, emergence rate, accelerated aging, seedling length, seedling dry mass and moisture content. Polymer application associated with seed treatment was efficient in reducing ...