Evaluation of Drug Dissolution Rate in Co-amorphous and Co-crystal Binary Drug Delivery Systems by Thermodynamic and Kinetic Methods

2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Chunhui Hu ◽  
Fabin Zhang ◽  
Haining Fan
2020 ◽  
Vol 21 ◽  
Author(s):  
Dickson Pius Wande ◽  
Qin Cui ◽  
Shijie Chen ◽  
Cheng Xu ◽  
Hui Xiong ◽  
...  

: As a unique and pleiotropic polymer, d-alpha-tocopheryl polyethylene glycol succinate (Tocophersolan) is a polymeric synthetic version of vitamin E. Tocophersolan has attracted enormous attention as a versatile excipient in different biomedical applications including drug delivery systems and nutraceuticals. The multiple inherent properties of Tocophersolan make it play flexible roles in drug delivery system design, including excipients with outstanding biocompatibility, solubilizer with the ability of promoting drug dissolution, drug permeation enhancer, P-glycoprotein inhibitor and anticancer compound. For these reasons, Tocophersolan has been widely used for improving the bioavailability of numerous pharmaceutical active ingredients. Tocophersolan has been approved by stringent regulatory authorities (such as US FDA, EMA, and PMDA) as a safe pharmaceutical excipient. In this review, we systematically curated current advances in nano-based delivery systems consisting of Tocophersolan with possibilities for futuristic applications in drug delivery, gene therapy, and nanotheranostic.


Author(s):  
Sunitha M Reddy ◽  
Sravani Baskarla

This article describes current strategies to enhance aqueous solubility and dissolution rate of poor soluble drugs. Most drugs in the market are lipophilic with low or poor water solubility. There are various methods to enhance solubility: co-solvency, particle size reduction, salt formation and Self Nanoemulsifying drug delivery systems, SEDDS is a novel approach to enhance solubility, dissolution rate and bioavailability of drugs. The study involves formulation and evaluation of solid self-Nano emulsifying drug delivery system (S-SNEDDS) to enhance aqueous solubility and dissolution rate. Oral route is the most convenient route for non-invasive administration. S-SNEDDS has more advantages when compared to the liquid self-emulsifying drug delivery system. Excipients were selected depends upon the drug compatibility oils, surfactants and co surfactants were selected to formulate Liquid SNEDDS these formulated liquid self-nano emulsifying drug delivery system converted into solid by the help of porous carriers, Melted binder or with the help of drying process. Conversion process of liquid to solid involves various techniques; they are spray drying; freeze drying and fluid bed coating technique; extrusion, melting granulation technique. Liquid SNEDDS has a high ability to improve dissolution and solubility of drugs but it also has disadvantages like incompatibility, decreased drug loading, shorter shelf life, ease of manufacturing and ability to deliver peptides that are prone to enzymatic hydrolysis.  


Pharmaceutics ◽  
2019 ◽  
Vol 11 (6) ◽  
pp. 267 ◽  
Author(s):  
Tao Yi ◽  
Jifen Zhang

Self-microemulsifying drug delivery systems (SMEDDS) offer potential for improving the oral bioavailability of poorly water-soluble drugs. However, their susceptibilities during long term storage and in vivo precipitation issues limit their successful commercial application. To overcome these limitations, SMEDDS can be solidified with solid carriers, thus producing solid self-microemulsifying drug delivery systems (S-SMEDDS). In this study, effects of various hydrophilic carriers on structural transitions and in vitro properties of S-SMEDDS were investigated in order to set up in vitro methods for screening out appropriate carriers for S-SMEDDS. Liquid SMEDDS was prepared and characterized using nimodipine as a model drug. The effects of various hydrophilic carriers on internal microstructure and solubilization of SMEDDS were investigated by conductivity measurement and in vitro dispersion test. The results showed that hydrophilic carriers including dextran 40, maltodextrin and PVP K30 seemed to delay the percolation transition of SMEDDS, allowing it to maintain a microstructure that was more conducive to drug dissolution, thus significantly increasing the solubilization of nimodipine in the self-microemulsifying system and decreasing drug precipitation when dispersed in simulated gastric fluid. S-SMEDDS of nimodipine were prepared by using spray drying with hydrophilic carriers. The effects of various hydrophilic carriers on in vitro properties of S-SMEDDS were investigated by using SEM, DSC, PXRD and in vitro dissolution. The results showed that properties of hydrophilic carriers, especially relative molecular mass of carriers, had obvious influences on surface morphologies of S-SMEDDS, reconstitution of microemulsion and physical state of nimodipine in S-SMEDDS. Considering that in vitro properties of S-SMEDDS are closely related to their pharmacokinetic properties in vivo, the simple and economical in vitro evaluation methods established in this paper can be used to screen solid carriers of S-SMEDDS well.


Pharmaceutics ◽  
2020 ◽  
Vol 12 (11) ◽  
pp. 1052
Author(s):  
Reem Abou Assi ◽  
Ibrahim M. Abdulbaqi ◽  
Toh Seok Ming ◽  
Chan Siok Yee ◽  
Habibah A. Wahab ◽  
...  

Azithromycin (AZM) is a macrolide antibiotic used for the treatment of various bacterial infections. The drug is known to have low oral bioavailability (37%) which may be attributed to its relatively high molecular weight, low solubility, dissolution rate, and incomplete intestinal absorption. To overcome these drawbacks, liquid (L) and solid (S) self-emulsifying drug delivery systems (SEDDs) of AZM were developed and optimized. Eight different pseudo-ternary diagrams were constructed based on the drug solubility and the emulsification studies in various SEDDs excipients at different surfactant to co-surfactant (Smix) ratios. Droplet size (DS) < 150 nm, dispersity (Đ) ≤ 0.7, and transmittance (T)% > 85 in three diluents of distilled water (DW), 0.1 mM HCl, and simulated intestinal fluids (SIF) were considered as the selection criteria. The final formulations of L-SEDDs (L-F1(H)), and S-SEDDs (S-F1(H)) were able to meet the selection requirements. Both formulations were proven to be cytocompatible and able to open up the cellular epithelial tight junctions (TJ). The drug dissolution studies showed that after 5 min > 90% and 52.22% of the AZM was released from liquid and solid SEDDs formulations in DW, respectively, compared to 11.27% of the pure AZM, suggesting the developed SEDDs may enhance the oral delivery of the drug. The formulations were stable at refrigerator storage conditions.


2016 ◽  
Vol 70 (5) ◽  
pp. 525-537 ◽  
Author(s):  
Marko Krstic ◽  
Svetlana Ibric

One of the problems with orally used drugs is their poor solubility, which can be overcame by creating solid self-nanoemulsifying drug delivery systems (SNEDDS). Aim is choosing appropriate SNEDDS using mixture design and adsorption of SNEDDS on a solid carrier to improve the dissolution rate of carbamazepine. Self-emulsifying drug delivery systems (SEDDS) consisting of oil phase (caprilic-capric triglycerides), a surfactant (Polisorbat 80 and Labrasol? (1:1)) and cosurfactant (Transcutol? HP) are formed by applying mixture design. 16 formulations were formulated, where proportion of lipids, surfactant and cosurfactant were varied (input parameters) in the following ranges: 10-30%, 40-60%, 30-50%, respectively. After dilution of SEDDS with water (90% water), the droplet size and polydispersity index (PdI) of the obtained emulsions (output parameters) were measured using photon correlation spectroscopy. After processing data, appropriate mathematical models that describe the dependence of input and output parameters were selected. The optimized SNEDDS was adsorbed on the carbamazepine and solid carrier physical mixture, containing 20% carbamazepine. Neusilin? UFl2, Neusilin? FL2, Sylysia? 320, diatomite were used as the carriers. The ratio of SNEDDS:carrier varied (1:1, 2:1). Dissolution testing was carried out in the rotation paddles apparatus. Caracterization of solid SNEDDS was performed using the hot stage microscopy (HSM), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), infrared spectrophotometry with Fourier transformation (FT-IR), scanning electron microscopy (SEM) and X-ray diffraction (PXRD). Selected SNEDDS consisting of lipids (21.12%), surfactant (42.24%) and cosurfactant (36.64%) had a droplet size 157.02?34.09 nm and PDI 0.184?0.021. Drug release profiles showed that in all formulations dissolution rate increased (the fastest drug release was observed in formulations with Sylysia? 320). It can be concluded that in all formulations carbamazepine is present in the thermodynamically most stable polymorphic form III. Formulation of solid SNEDDS can significantly increase dissolution rate carbamazepine, with conservation of the polymorphic form III CBZ and potentially increased bioavailability.


Author(s):  
G.E. Visscher ◽  
R. L. Robison ◽  
G. J. Argentieri

The use of various bioerodable polymers as drug delivery systems has gained considerable interest in recent years. Among some of the shapes used as delivery systems are films, rods and microcapsules. The work presented here will deal with the techniques we have utilized for the analysis of the tissue reaction to and actual biodegradation of injectable microcapsules. This work has utilized light microscopic (LM), transmission (TEM) and scanning (SEM) electron microscopic techniques. The design of our studies has utilized methodology that would; 1. best characterize the actual degradation process without artifacts introduced by fixation procedures and 2. allow for reproducible results.In our studies, the gastrocnemius muscle of the rat was chosen as the injection site. Prior to the injection of microcapsules the skin above the sites was shaved and tattooed for later recognition and recovery. 1.0 cc syringes were loaded with the desired quantity of microcapsules and the vehicle (0.5% hydroxypropylmethycellulose) drawn up. The syringes were agitated to suspend the microcapsules in the injection vehicle.


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