International Journal of Biological Macromolecules 104 (2017) 1229–1237 Contents lists available at ScienceDirect International Journal of Biological Macromolecules j ourna l h o mepa ge: www.elsevier.com/locate/ijbiomac Kondogogu gum-Zn +2 -pectinate emulgel matrices reinforced with mesoporous silica for intragastric furbiprofen delivery Hriday Bera a,b,∗ , Jhansirani Nadimpalli b , Sanoj Kumar b , Pavani Vengala b a Faculty of Pharmacy, AIMST University, Semeling, Kedah,08100, Malaysia b Gokaraju Rangaraju College of Pharmacy, Bachupally, Hyderabad, 500090, India a r t i c l e i n f o Article history: Received 13 April 2017 Received in revised form 28 May 2017 Accepted 4 July 2017 Available online 5 July 2017 Keywords: Low methoxyl pectin Kondogogu gum Calcium silicate Emulgel systems Floatation Mucoadhesion a b s t r a c t Flurbiprofen (FLU), a non-steroidal anti-inflammatory drug, exhibits limited clinical response due to its poor physicochemical properties. This study aimed at developing reliable drug carriers for intrgas- tric FLU delivery with a view to improve biopharmaceutical characteristics of drug and modulate its release in a controlled manner. In this context, FLU-loaded kondogogu gum (KG)-Zn +2 -low methoxyl (LM) pectinate emulgel matrices reinforced with calcium silicate (CS) were accomplished by ionotropic gelation technique employing zinc acetate as cross-linker and characterized for their in vitro perfor- mances. All the formulations demonstrated excellent drug encapsulation efficiency (DEE, 46–87%) and sustained drug release behavior (Q 7h , 70–91%). These quality attributes were remarkably influenced by polymer-blend (LM pectin:KG) ratios, low-density oil types and CS inclusion. The drug release profile of the FLU-loaded optimized matrices (F-7) was best fitted in Korsmeyer-Peppas model with Fickian diffusion driven mechanism. It also conferred excellent in vitro gastroretention capabilities. Moreover, the drug-excipient compatibility, alteration of crystallinity and thermal behavior of drug and surface morphology of matrices were evidenced with the results of FTIR, XRD, DSC and SEM analyses, respec- tively. Thus, the newly developed matrices are appropriate for sustained intragastric FLU delivery and simultaneous zinc supplementation for effective inflammation and arthritis management. © 2017 Elsevier B.V. All rights reserved. 1. Introduction Flurbiprofen (FLU), a non-steroidal anti-inflammatory agent of 2-arylpropionic acid class, is most widely prescribed drug for inflammation and arthritis management [1]. It acts by blocking the action of cyclooxyganase enzyme and eventually controls the pro- duction of prostaglandins. However, FLU belongs to the BCS class II and displays poor aqueous solubility. The poor inherent solu- bility and slow dissolution rate in the gastrointestinal lumen give rise to extremely variable oral bioavailability and limited clinical response of FLU. Moreover, it exhibits a shorter half-life (3.9 h) and produces ulcerogenic adverse effect with abdominal discom- fort [2]. Hence, there is an unmet need to develop an intelligent carrier for sustained FLU delivery. An array of scientific investiga- tions adopted numerous approaches to overcome the challenges associated with FLU therapy exemplified by FLU-in-cyclodextrin- in-liposomes [3], FLU-loaded nanostructured lipid carriers based ∗ Corresponding author at: Faculty of Pharmacy, AIMST University, Semeling, Kedah, 08100, Malaysia. E-mail address: hriday.bera1@gmail.com (H. Bera). topical gel [2], FLU-microemulsion [4], FLU-entrapped cross-linked chitosan microspheres [5] and so on with diverse degrees of success. In today’s pharmaceutical arena, emulgels, comprising oil-in-water emulsions within the gel matrices, have emerged as attractive drug delivery platforms for hydrophobic drugs as they offer the advantages of both emulsions and gels [6]. Recent investi- gations have exploited various naturally occurring polysaccharides such as alginate, pectin, tamarind gum, sterculia gum etc. to accom- plish stable emulgel systems as drug carriers [7–9]. Kondagogu gum (KG) is a plant-derived substituted rhamno- galacturonans obtained from Cochlospermum gossypium DC (Family Bixaceae). KG is composed of arabinose, galactose, rhamnose, glu- cose, mannose, glucuronic acid and galacturonic acid, with sugar linkage of (1 → 2) -d-Gal p, (1 → 6) -d-Gal p, (1 → 4) -d-Glc p, 4-O-Me--d-Glc p, (1 → 2) -l-Rha and (1 → 4) -d-Gal p. It dis- plays outstanding gelling, emulsifying and thickening properties [10]. Thus, KG could be utilized to fabricate stable emulgels contain- ing various low-density oils. The oil-entrapped KG based emulgels could display buoyant property due to their low density. In addi- tion, the oil phase might impose an effective blockade towards drug eluting from the matrices, which results in enhanced drug entrapment with retarded drug release behavior. Therefore, these http://dx.doi.org/10.1016/j.ijbiomac.2017.07.027 0141-8130/© 2017 Elsevier B.V. All rights reserved.