scholarly journals Nanocrystalization: An Emerging Technology to Enhance the Bioavailability of Poorly Soluble Drugs

2019 ◽  
Vol 7 (4) ◽  
pp. 259-278 ◽  
Author(s):  
Kavita Joshi ◽  
Akhilesh Chandra ◽  
Keerti Jain ◽  
Sushama Talegaonkar

Most of the active pharmaceutical ingredient used in the management of disease have poor water solubility and offer grueling problems in drug formulation development since low solubility is generally associated with poor dissolution characteristics which leads to poor oral bioavailability. The great challenge for the development of a pharmaceutical product is to create its new formulation and drug delivery system to limit solubility problems of existing drug candidate. Limited drug-loading capacity requires a large amount of carrier material to get appropriate encapsulation of the drug, which is another major challenge in the development of pharmaceutical product which could be resolved by developing nanocrystals (NCs). A significant research in the past few years has been done to develop NCs which helps in the delivery of poorly water soluble drugs via different routes. The technology could continue to thrive as a useful tool in pharmaceutical sciences for the improvement of drug solubility, absorption and bioavailability. Many crystalline compounds have pulled in incredible consideration much of the time, due to their ability to show good physical and chemical properties when contrasted with their amorphous counterparts. Nanocrystals have been proven to show atypical properties compared to the bulk. This review article explores the principles of the important nanocrystallization techniques including NCs characterization and its application.

Author(s):  
ARIF BUDIMAN

Solubility of the drug has a strong influence to achieve higher bioavailability of the drug in systemic circulation. More than 70% NCEs (new chemical entities) are hydrophobic, and practically difficult into solid formulation due to their poor water solubility. Mesoporous silicas (MSP) have been used for drug delivery system, especially for poorly water-soluble drugs. Encapsulation and interaction of drugs in MSP can enhance the delivery and maintain the stability of the drug. However, the characterization of the drug in MSP is necessary to confirm its molecular state. In this review, we present an overview of reports related to the characterization of drug encapsulated into MSP. Encapsulation of drugs in MSP can prevent recrystallization of drugs due to its inhibition of crystal nucleation. A porous material in MSP can maintain the drug in a physically stable amorphous state. The preventing of drug crystallization in MSP can enhance the solubility and the dissolution rate of drug. Therefore, in this work, attempts have been made to understand the molecular state of the drug in MSP. The physicochemical characterization of drug by transmission electron microscopy (TEM), scanning electron microscope (SEM), differential scanning calorimetry (DSC), fourier-transform infrared spectroscopy (FTIR), powder x-ray diffraction (PXRD) and thermogravimetric analysis (TGA) were discussed. The effect of solvent and methods of drug loading and the effect of the shape of MSP on release profiles are also presented. Overall, this review provides information about the characterization of drug encapsulated into MSP which will be useful in pharmaceutical formulation development.


2017 ◽  
Vol 23 (3) ◽  
pp. 350-361 ◽  
Author(s):  
Hisham Al-Obaidi ◽  
Mridul Majumder ◽  
Fiza Bari

Crystalline and amorphous dispersions have been the focus of academic and industrial research due to their potential role in formulating poorly water-soluble drugs. This review looks at the progress made starting with crystalline carriers in the form of eutectics moving towards more complex crystalline mixtures. It also covers using glassy polymers to maintain the drug as amorphous exhibiting higher energy and entropy. However, the amorphous form tends to recrystallize on storage, which limits the benefits of this approach. Specific interactions between the drug and the polymer may retard this spontaneous conversion of the amorphous drug. Some studies have shown that it is possible to maintain the drug in the amorphous form for extended periods of time. For the drug and the polymer to form a stable mixture they have to be miscible on a molecular basis. Another form of solid dispersions is pharmaceutical co-crystals, for which research has focused on understanding the chemistry, crystal engineering and physico-chemical properties. USFDA has issued a guidance in April 2013 suggesting that the co-crystals as a pharmaceutical product may be a reality; but just not yet! While some of the research is still oriented towards application of these carriers, understanding the mechanism by which drug-carrier miscibility occurs is also covered. Within this context is the use of thermodynamic models such as Flory-Huggins model with some examples of studies used to predict miscibility.


Author(s):  
Poovi Ganesan ◽  
N Damodharan

Background: A better understanding of the biopharmaceutical and physicochemical properties of drugs and the pharmaco-technical factors would be of great help for developing pharmaceutical products. But, it is extremely difficult to study the effect of each variable and interaction among them through the conventional approach Objective: To screen the most influential factors affecting the particle size (PS) of lipid nanoparticle (LNPs) (solid lipid nanoparticle (SLN) and nanostructured lipid carrier (NLC)) for poorly water-soluble BCS class-II drug like tamoxifen (TMX) to improve its oral bioavailability and to reduce its toxicity to tolerable limits using Taguchi (L12 (2 11)) orthogonal array design by applying computer optimization technique. Results: The size of all LNPs formulations prepared as per the experimental design varied between 172 nm and 3880 μm, polydispersity index between 0.033 and 1.00, encapsulation efficiency between 70.8% and 75.7%, and drug loading between 5.84% and 9.68%. The study showed spherical and non-spherical as well as aggregated and non-aggregated LNPs. Besides, it showed no interaction and amorphous form of the drug in LNPs formulation. The Blank NLCs exhibited no cytotoxicity on MCF-7 cells as compared to TMX solution, SLNs (F5) and NLCs (F12) suggests that the cause of cell death is primarily from the effect of TMX present in NLCs. Conclusions: The screening study clearly showed the importance of different individual factors significant effect for the LNPs formulation development and its overall performance in an in-vitro study with minimum experimentation thus saving considerable time, efforts, and resources for further in-depth study.


Nanomaterials ◽  
2021 ◽  
Vol 11 (9) ◽  
pp. 2196 ◽  
Author(s):  
Silvana Alfei ◽  
Anna Maria Schito ◽  
Guendalina Zuccari

Ursolic acid (UA) is a pentacyclic triterpenoid found in many medicinal plants and aromas endowed with numerous in vitro pharmacological activities, including antibacterial effects. Unfortunately, UA is poorly administered in vivo, due to its water insolubility, low bioavailability, and residual systemic toxicity, thus making urgent the development of water-soluble UA formulations. Dendrimers are nonpareil macromolecules possessing highly controlled size, shape, and architecture. In dendrimers with cationic surface, the contemporary presence of inner cavities and of hydrophilic peripheral functions, allows to encapsulate hydrophobic non-water-soluble drugs as UA, to enhance their water-solubility and stability, and to promote their protracted release, thus decreasing their systemic toxicity. In this paper, aiming at developing a new UA-based antibacterial agent administrable in vivo, we reported the physical entrapment of UA in a biodegradable not cytotoxic cationic dendrimer (G4K). UA-loaded dendrimer nanoparticles (UA-G4K) were obtained, which showed a drug loading (DL%) much higher than those previously reported, a protracted release profile governed by diffusion mechanisms, and no cytotoxicity. Also, UA-G4K was characterized by principal components analysis (PCA)-processed FTIR spectroscopy, by NMR and elemental analyses, and by dynamic light scattering experiments (DLS). The water solubility of UA-G4K was found to be 1868-fold times higher than that of pristine UA, thus making its clinical application feasible.


Author(s):  
Gavaskar Basani ◽  
Madhusudan Rao Yamsani ◽  
Ramya Sri Sura

The aim of current work was to grow extended release multiple unit pellets of Tamsulosin Hydrochloride, is an alpha-blocker, used for the healing of the symptoms of a prostate gland condition called BPH (benign prostatic hyperplasia) by extrusion- spheronization (E/S) and solution/suspension layering (S/S) method. In the Extrusion-Spheronization, A ratio of 75:25, 67:33, 64:36 Tamsulosin Hydrochloride and Microcrystalline cellulose were mixed for making drug pellets and extended release (ER) coating was performed in fluidized bed processor (FBP) by solution/suspension layering with Ethyl cellulose (aqueous. dispersion, 4 cps and 7 cps) and Hypromellose (5cps) with different ratios % weight buildups accordingly. In the Solution/suspension layering (S/S) method, Tamsulosin Hydrochloride drug pellets were prepared by layering onto MCC spheres in FBP. These drug pellets were further coated for extended release with HPMC, 5cps and EC, 7cps. In drug coating stage, drug and different binder (Hypromellose, 5 cps) concentrations 8, 10, 12, 14 mg/unit were coated onto the cores for optimization of binder concentration. The weight of MCC spheres were optimized for further formulations. For all the drug coated pellets, ER coating was given with EC, 7cps and HPMC, 5 cps at a coating level of 8% weight by weight. In the extrusion- spheronization (E/S) Optimization of Drug pellets: Among the trials TD3 (Tamsulosin HCl and MCC) showed good mechanical strength with better yield due to increased MCC concentration. Optimization of Extended Release Coating: Optimized TD3 drug pellets were coated with ER coating using water insoluble polymer (Aq.EC 25% dispersion/ EC, 4cps/ EC, 7cps) and water soluble polymer (HPMC, 5cps). Among these polymers, extended release coating was optimized (TD3E14) with the combination of EC, 7cps and HPMC, 5cps at 8% weight build up. In the Solution/Suspension layering: Optimization of binder concentration in drug coating stage: HPMC, 5cps with 12 mg/unit for TF7 was optimized based on %yield. Optimization of MCC spheres in drug coating stage in formulation of ER pellets with different weight drug pellets: The weight of MCC spheres (160, 170, 180, 190 mg/unit) used in the drug coating stage with binder HPMC, 5cps (12 mg/unit). These drug pellets were given with ER coating at 8% weight buildup by using EC, 7cps and HPMC, 5cps. Among these trials, TF7E7 was optimized. Based on the investigations of the present study, conclusions was. formulating low dose, high soluble, BCS class I drug- Tamsulosin Hydrochloride ER formulation by extrusion-spheronization showed flexibility for batch processing and cost effectiveness while solution/suspension layering was process feasible but time consuming due to high drug loading.


Pharmaceutics ◽  
2019 ◽  
Vol 11 (11) ◽  
pp. 573 ◽  
Author(s):  
Wang ◽  
Wu ◽  
Wang ◽  
Wang ◽  
Zhao

Honokiol (HK), a well-tolerated natural product, has many multiple pharmacological activities. However, its poor water solubility and low bioavailability limit its clinical application and development. The aim of this research was to prepare the solid dispersion (SD) formulation of honokiol (HK) with poloxamer-188 (PLX) as the carrier, thereby improving its solubility and oral bioavailability. Firstly, by investigating the relationship between the addition amount of the PLX and the solubility of HK, and the effects of solid dispersions with different ratios of HK–PLX on the solubility of HK, we determined that the optimum ratio of PLX to HK was (1:4). Then, the HK–PLX (1:4) SD of HK was prepared using the solvent evaporation method. The morphology of the obtained HK–PLX (1:4) SD was different from that of free HK. The HK in the HK–PLX (1:4) SD existed in amorphous form and formed intermolecular hydrogen bonds with PLX. Additionally, the solubility values of the HK–PLX (1:4) SD were about 32.43 ± 0.36 mg/mL and 34.41 ± 0.38 mg/mL in artificial gastric juice (AGJ) and in artificial intestinal juice (AIJ), respectively. Compared with free HK, the release rate and the bioavailability was also substantially improved for HK in its SD form. 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay indicated that the HK–PLX (1:4) SD showed higher inhibition of HepG2 cells than free HK. Taken together, the present study suggests that the HK–PLX (1:4) SD could become a new oral drug formulation with high bioavailability and could produce a better response for clinical applications of HK.


2014 ◽  
Vol 5 (19) ◽  
pp. 5775-5783 ◽  
Author(s):  
Lin Dai ◽  
Dan Li ◽  
Jing Cheng ◽  
Jing Liu ◽  
Li-Hong Deng ◽  
...  

Multiarm-polyethylene glycol–betulinic acid prodrugs were prepared by using multiarm-polyethylene glycol linkers and betulinic acid, which exhibited high drug loading capacity, good water solubility, and excellent anticancer activity.


2019 ◽  
Vol 9 (2) ◽  
pp. 583-590 ◽  
Author(s):  
Sandip R. Pawar ◽  
Shashikant D. Barhate

The solubility of a solute is the maximum quantity of solute that can dissolve in a certain quantity of solvent or quantity of solution at a specified temperature. Solubility is one of the important parameter to achieve desired concentration of drug in systemic circulation for pharmacological response to be shown. Solubility is essential for the therapeutic effectiveness of the drug, independent of the route of administration. Low aqueous solubility is the major problem encountered with formulation development of new chemical entities as well as for the generic development. Poorly soluble drugs are often a challenging task for formulators in the industry Conventional  approaches  for  enhancement  of  solubility  have  limited  applicability,  especially when  the  drugs  are  poorly  soluble  simultaneously  in  aqueous  and  in  non-aqueous  media. Drug with poor water solubility cause slow dissolution rates, generally show erratic and incomplete absorption leading to low bioavailability when administered orally. Solubilization may be affected by cosolvent water  interaction, micellar solubilization, reduction in  particle  size,  inclusion  complexes,  solid  dispersion,  and  change  in  polymorph.  Some  new technologies  are  also  available  to  increase  the  solubility  like  micro emulsion,  self-emulsifying drug  delivery  system  and  supercritical  fluid  technology. This present review details about the different approaches used for the enhancement of the solubility of poorly water-soluble drugs include particle size reduction, nanonization, pH adjustment, solid dispersion, complexation, co‐solvency, hydrotropy etc. The purpose of this article is to describe the techniques of solubilization for the attainment of effective absorption and improved bioavailability. Keywords: Solubility, Solubility Enhancement, bioavailability, solid dispersion, Solid Dispersion, Solubilization.


Pharmaceutics ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 366
Author(s):  
Sonja Schertel ◽  
Sharareh Salar-Behzadi ◽  
Andreas Zimmer

Hot melt coating (HMC) of an active pharmaceutical ingredient (API) powder with lipid-based excipients is an innovative method for manufacturing patient-convenient dosage forms. However, drug release instability is still its main industrial challenge. The correlation between the unstable pharmaceutical product performance with the solid-state alteration of lipids is currently well-investigated. The remaining problem is the inconsistent release alteration of different APIs coated with the same lipid after storage, such as faster release in some cases and slower release in others. The interaction between API surface and lipid-based coating and its alteration during storage were investigated in this work. The surface properties of five different APIs and the coating composition of tripalmitin and polysorbate 65 were screened via Washburn and pendant drop methods, respectively. Metformin hydrochloride and hydrochlorothiazide particles were each coated with the coating composition. The water sorption alteration of coated particles and the crystal growth of tripalmitin in the coating after storage were measured via tensiometry and X-ray diffraction. The cleavage work necessary to overcome the adhesion of coating composition on the core surface was calculated for each API. The accelerated release of the polar core (metformin) after storage was correlated with a low cleavage work and a distinctive phase separation. In contrast, a decelerated release of the hydrophobic core (hydrochlorothiazide) was favored by the crystal growth of the lipid-based coating. The gained knowledge can be used to design the product stability during the formulation development.


2018 ◽  
Vol 8 (5) ◽  
pp. 44-49 ◽  
Author(s):  
SD Mankar ◽  
Punit R. Rach

The solubility behavior of drugs remains one of the most exigent aspects in formulation development. With the advent of combinatorial chemistry and high throughput screening, the number of poorly water soluble compounds has dramatically increased.  Among all the newly discovered chemical entities, about 40-45% drugs fail to reach market due to their poor water solubility. Because of solubility problem, bioavailability of drugs gets affected and hence solubility enhancement becomes necessary. Solid dispersions have attracted considerable interest as an efficient means of improving the dissolution rate and hence the bioavailability of drugs. Therefore, the application of this technique proves to be an important stratagem for pharmaceutical companies. However, the in - depth knowledge of the solid dispersion is desired for the scale up of formulation, from laboratory scale to industrial scale. There are various methods available to improve the solubility of the new drug in which solid dispersion emerged promising. A Solid dispersion generally composed of two components- the drug and the polymer matrix. Hence, this approach is expected to form a basis for the commercialization of many poorly water-soluble and water-insoluble drugs in their solid-dispersion formulations in the near future. This article reviews the various preparation techniques, carriers used, advantages and limitations of solid dispersions and compiles some of the recent advances. Keywords: Bioavailability, Solid Dispersion, Hydrophilic carriers, Polyethylene glycol.


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