Drug Deliv. and Transl. Res. (2011) 1:322–331 DOI 10.1007/s13346-011-0033-3
RESEARCH ARTICLE
Comparative oral bioavailability advantage from curcumin formulations Bhushan Munjal & Yogesh Bapurao Pawar & Sarsvatkumar Babulal Patel & Arvind Kumar Bansal
Published online: 11 May 2011 # Controlled Release Society 2011
Abstract The aim of the present study was to study the oral bioavailability of seven different formulations of curcumin (CRM). CRM formulations viz. aqueous suspension, micronized suspension, nanosuspension, amorphous solid dispersion, hydroxypropyl-β-cyclodextrin (HP-β-CD) inclusion complex, combination with piperine, and spraydried CRM–milk composite were compared for oral bioavailability in male Sprague–Dawley rats at a CRM dose of 250 mg/kg body weight using a validated highperformance liquid chromatography method. Aqueous suspension provided a Cmax and AUC(0−t) of 28.9 ng/ml and 26.9 ng h/ml, respectively. In comparison, statistically significant increase in the oral bioavailability was obtained with the nanosuspension, HP-β-CD inclusion complex, and amorphous solid dispersion with 251%, 567%, and 446% increase in terms of AUC(0−t) and 405%, 415%, and 270% in terms of Cmax. However, no significant increase in AUC(0 − t) and Cmax was observed with piperine and micronized suspension. The milk composite reduced the oral bioavailability of CRM (10% and 37% in terms of AUC(0−t) and Cmax). A statistically significant increase in the Tmax was observed with piperine and in HP-β-CD complex, while the Tmax was reduced for nanosuspension. The results provide interesting insights into the role of solubility enhancement and metabolism inhibition, for improving the oral bioavailability of CRM. Keywords Curcumin . Oral bioavailability . Formulations
B. Munjal : Y. B. Pawar : S. B. Patel : A. K. Bansal (*) Department of Pharmaceutics, National Institute of Pharmaceutical Education and Research (NIPER), Sector-67, S.A.S. Nagar, Punjab 160062, India e-mail: [email protected]
Introduction Curcumin (CRM; Fig. 1), owing to diverse pharmacological actions and lack of major side effects, is undergoing clinical trials for several diseases like ulcerative colitis, colon cancer, pancreatic cancer, hypercholesterolemia, atherosclerosis, pancreatitis, psoriasis, Crohn’s disease, and neurological diseases [1]. Clinical development of CRM into a “medicine” has been hampered by its extremely poor oral bioavailability [2]. Reasons reported for its poor oral bioavailability include poor aqueous solubility, degradation in gastrointestinal tract (GIT) at neutral and alkaline pH, high pre-systemic metabolism in the intestinal wall, rapid metabolism to sulfate and glucuronide conjugates leading to short half-life, and rapid systemic elimination [2, 3, 4]. Recently, our research group assessed the permeability of CRM using Caco-2 cell model and found that CRM was poorly permeable with a Papp (A → B) value of 2.93 ± 0.94 × 10−6 cm/s and can be classified as a Biopharmaceutic Classification System class IV molecule [5]. Numerous formulation approaches have been investigated to overcome delivery barriers of CRM. Various oral formulations like self-emulsifying drug delivery system [6, 7], phospholipid complexes [8, 9], solid lipid nanoparticles [10, 11], nanocrystal dispersion [12], cyclodextrin complex [13], polymeric nanoparticles [14, 15], nanoemulsions [16], Biocurcumax™ [17], amorphous solid dispersion [18], and Bioperine [19] have been investigated. Injectable formulations viz. polymeric implants [20], nanosuspension [21], polymeric nanoparticles [22], polymeric micelles [23], liposomes [24], and microspheres [25] have also been explored. Topical formulations of CRM like solid lipid nanoparticles [26] and nanoemulsions [27] are also reported.
Drug Deliv. and Transl. Res. (2011) 1:322–331
323
Calculation of quantitative biopharmaceutical parameters Quantitative biopharmaceutical parameters viz. dissolution time (Tdisso) and absorbable dose (Dabs) were calculated using the following equations [28]: Fig. 1 Chemical structure of curcumin
Information related to bioavailability assessment of the above formulations varies significantly in terms of dose employed, route of administration, animal species employed and bioanalytical method for CRM quantification in plasma. Moreover, many of the reported studies were confined to in vitro evaluation of formulations. This prevents meaningful comparison of the various formulation approaches in terms of their bioavailability advantage. In the present study, we have employed seven different formulation strategies viz. aqueous suspension (AS), micronization (micronized suspension, MS), nanonization (nanosuspension, NS), amorphous solid dispersion (ASD), hydroxypropyl-β-cyclodextrin (HP-β-CD) inclusion complex (HIC), concomitant administration with piperine as bioenhancer (WP), and spray-dried CRM–milk composite (MC) and compared their oral bioavailability in male Sprague–Dawley (SD) rats. This shall allow a direct comparison of various formulation approaches vis-à-vis improvement in oral bioavailability.
Materials and methods Materials CRM (purity more than 99% by high-performance liquid chromatography (HPLC) assay) was extracted from Curcuma longa (turmeric). 4-Methoxychalcone (4-MC) and piperine were purchased from Sigma-Aldrich (Steinheim, Germany). HPLC grade methanol, ethyl acetate, acetonitrile (ACN), and tetrahydrofuran (THF) were purchased from RFCL Ltd. (New Delhi, India). Acetone and citric acid monohydrate were purchased from Merck (Mumbai, India), glacial acetic acid was procured from Qualigens Fine Chemicals (Mumbai, India), polyvinylpyrrolidone K-30 (PVP) was procured from ISP Technologies Inc. (Wayne, NJ, USA), sodium carboxymethyl cellulose (Na-CMC) was from Himedia Laboratories Ltd. (Mumbai, India), poloxamer 188 was from BASF (Ludwigshafen, Germany), and HP-β-CD was from Wacker Chemie (Munich, Germany). Pasteurized standardized milk (fat content 4.5 g/100 ml) was obtained from Verka (Mohali, India). Ultrapure water was produced by purification with Ultra pure® water system (USF Elga, England).
Tdisso ¼
hrr 3DCs
ð1Þ
where h is the diffusion layer thickness, ρ is the density of the material, r is the radius of particle, D is the diffusion coefficient, and Cs is the solubility in milligrams per milliliter. Dabs ¼ Peff Cs A MITT
ð2Þ
where MITT is the mean intestinal transit time assumed to be 199 min and Peff is the effective permeability and A is the intestinal area. Preparation of formulations The composition of the prepared formulations is depicted in Table 1. The AS was prepared by suspending CRM in citrophosphate buffer pH 5.0 containing Na-CMC. The buffer was prepared by mixing 48.5 ml of 0.1 M citric acid solution with 0.2 M disodium hydrogen phosphate sufficient to bring the pH to 5.0. Micronization of CRM was achieved using air-jet mill (AS 50, Hosokawa Alpine Aktiengesellschaft, Germany) with the following parameters: compressed air pressure 6 kg/cm2, grinding air pressure 5 bar, propellant air pressure 2 bar, feed rate 0.9 g/min, and amplitude 25–30. Micronized CRM was suspended in citro-phosphate buffer pH 5.0. NS was prepared by dispersing micronized CRM in citro-phosphate buffer of pH 5.0 containing poloxamer 188 using high-speed homogenizer (IKA-Ultraturrax; IKAWerke GmbH & Co., Germany) at 8,000 rpm for 5 min, in Table 1 Composition of the CRM formulations Component
CRM Na-CMC Poloxamer PVP HP-β-CD Piperine Milk
Quantity (mg) AS
MS
NS
ASD
HIC
WP
MC
50 4 – – – – –
50 4 – – – – –
50 – 4 – – – –
50 – – 50 – – –
50 – – – 315 – –
50 4 – – – 4 –
50 – – – – – 4,000
CRM curcumin, Na-CMC sodium carboxymethyl cellulose, PVP polyvinylpyrrolidone, HP-β-CD hydroxypropyl-β-cyclodextrin, AS aqueous suspension, MS micronized suspension, NS nanosuspension, ASD amorphous solid dispersion, HIC HP-β-CD inclusion complex, WP with piperine, MC milk composite
324
an ice bath. In the second step, the chilled formulation (temperature0.9921 (
RESEARCH ARTICLE
Comparative oral bioavailability advantage from curcumin formulations Bhushan Munjal & Yogesh Bapurao Pawar & Sarsvatkumar Babulal Patel & Arvind Kumar Bansal
Published online: 11 May 2011 # Controlled Release Society 2011
Abstract The aim of the present study was to study the oral bioavailability of seven different formulations of curcumin (CRM). CRM formulations viz. aqueous suspension, micronized suspension, nanosuspension, amorphous solid dispersion, hydroxypropyl-β-cyclodextrin (HP-β-CD) inclusion complex, combination with piperine, and spraydried CRM–milk composite were compared for oral bioavailability in male Sprague–Dawley rats at a CRM dose of 250 mg/kg body weight using a validated highperformance liquid chromatography method. Aqueous suspension provided a Cmax and AUC(0−t) of 28.9 ng/ml and 26.9 ng h/ml, respectively. In comparison, statistically significant increase in the oral bioavailability was obtained with the nanosuspension, HP-β-CD inclusion complex, and amorphous solid dispersion with 251%, 567%, and 446% increase in terms of AUC(0−t) and 405%, 415%, and 270% in terms of Cmax. However, no significant increase in AUC(0 − t) and Cmax was observed with piperine and micronized suspension. The milk composite reduced the oral bioavailability of CRM (10% and 37% in terms of AUC(0−t) and Cmax). A statistically significant increase in the Tmax was observed with piperine and in HP-β-CD complex, while the Tmax was reduced for nanosuspension. The results provide interesting insights into the role of solubility enhancement and metabolism inhibition, for improving the oral bioavailability of CRM. Keywords Curcumin . Oral bioavailability . Formulations
B. Munjal : Y. B. Pawar : S. B. Patel : A. K. Bansal (*) Department of Pharmaceutics, National Institute of Pharmaceutical Education and Research (NIPER), Sector-67, S.A.S. Nagar, Punjab 160062, India e-mail: [email protected]
Introduction Curcumin (CRM; Fig. 1), owing to diverse pharmacological actions and lack of major side effects, is undergoing clinical trials for several diseases like ulcerative colitis, colon cancer, pancreatic cancer, hypercholesterolemia, atherosclerosis, pancreatitis, psoriasis, Crohn’s disease, and neurological diseases [1]. Clinical development of CRM into a “medicine” has been hampered by its extremely poor oral bioavailability [2]. Reasons reported for its poor oral bioavailability include poor aqueous solubility, degradation in gastrointestinal tract (GIT) at neutral and alkaline pH, high pre-systemic metabolism in the intestinal wall, rapid metabolism to sulfate and glucuronide conjugates leading to short half-life, and rapid systemic elimination [2, 3, 4]. Recently, our research group assessed the permeability of CRM using Caco-2 cell model and found that CRM was poorly permeable with a Papp (A → B) value of 2.93 ± 0.94 × 10−6 cm/s and can be classified as a Biopharmaceutic Classification System class IV molecule [5]. Numerous formulation approaches have been investigated to overcome delivery barriers of CRM. Various oral formulations like self-emulsifying drug delivery system [6, 7], phospholipid complexes [8, 9], solid lipid nanoparticles [10, 11], nanocrystal dispersion [12], cyclodextrin complex [13], polymeric nanoparticles [14, 15], nanoemulsions [16], Biocurcumax™ [17], amorphous solid dispersion [18], and Bioperine [19] have been investigated. Injectable formulations viz. polymeric implants [20], nanosuspension [21], polymeric nanoparticles [22], polymeric micelles [23], liposomes [24], and microspheres [25] have also been explored. Topical formulations of CRM like solid lipid nanoparticles [26] and nanoemulsions [27] are also reported.
Drug Deliv. and Transl. Res. (2011) 1:322–331
323
Calculation of quantitative biopharmaceutical parameters Quantitative biopharmaceutical parameters viz. dissolution time (Tdisso) and absorbable dose (Dabs) were calculated using the following equations [28]: Fig. 1 Chemical structure of curcumin
Information related to bioavailability assessment of the above formulations varies significantly in terms of dose employed, route of administration, animal species employed and bioanalytical method for CRM quantification in plasma. Moreover, many of the reported studies were confined to in vitro evaluation of formulations. This prevents meaningful comparison of the various formulation approaches in terms of their bioavailability advantage. In the present study, we have employed seven different formulation strategies viz. aqueous suspension (AS), micronization (micronized suspension, MS), nanonization (nanosuspension, NS), amorphous solid dispersion (ASD), hydroxypropyl-β-cyclodextrin (HP-β-CD) inclusion complex (HIC), concomitant administration with piperine as bioenhancer (WP), and spray-dried CRM–milk composite (MC) and compared their oral bioavailability in male Sprague–Dawley (SD) rats. This shall allow a direct comparison of various formulation approaches vis-à-vis improvement in oral bioavailability.
Materials and methods Materials CRM (purity more than 99% by high-performance liquid chromatography (HPLC) assay) was extracted from Curcuma longa (turmeric). 4-Methoxychalcone (4-MC) and piperine were purchased from Sigma-Aldrich (Steinheim, Germany). HPLC grade methanol, ethyl acetate, acetonitrile (ACN), and tetrahydrofuran (THF) were purchased from RFCL Ltd. (New Delhi, India). Acetone and citric acid monohydrate were purchased from Merck (Mumbai, India), glacial acetic acid was procured from Qualigens Fine Chemicals (Mumbai, India), polyvinylpyrrolidone K-30 (PVP) was procured from ISP Technologies Inc. (Wayne, NJ, USA), sodium carboxymethyl cellulose (Na-CMC) was from Himedia Laboratories Ltd. (Mumbai, India), poloxamer 188 was from BASF (Ludwigshafen, Germany), and HP-β-CD was from Wacker Chemie (Munich, Germany). Pasteurized standardized milk (fat content 4.5 g/100 ml) was obtained from Verka (Mohali, India). Ultrapure water was produced by purification with Ultra pure® water system (USF Elga, England).
Tdisso ¼
hrr 3DCs
ð1Þ
where h is the diffusion layer thickness, ρ is the density of the material, r is the radius of particle, D is the diffusion coefficient, and Cs is the solubility in milligrams per milliliter. Dabs ¼ Peff Cs A MITT
ð2Þ
where MITT is the mean intestinal transit time assumed to be 199 min and Peff is the effective permeability and A is the intestinal area. Preparation of formulations The composition of the prepared formulations is depicted in Table 1. The AS was prepared by suspending CRM in citrophosphate buffer pH 5.0 containing Na-CMC. The buffer was prepared by mixing 48.5 ml of 0.1 M citric acid solution with 0.2 M disodium hydrogen phosphate sufficient to bring the pH to 5.0. Micronization of CRM was achieved using air-jet mill (AS 50, Hosokawa Alpine Aktiengesellschaft, Germany) with the following parameters: compressed air pressure 6 kg/cm2, grinding air pressure 5 bar, propellant air pressure 2 bar, feed rate 0.9 g/min, and amplitude 25–30. Micronized CRM was suspended in citro-phosphate buffer pH 5.0. NS was prepared by dispersing micronized CRM in citro-phosphate buffer of pH 5.0 containing poloxamer 188 using high-speed homogenizer (IKA-Ultraturrax; IKAWerke GmbH & Co., Germany) at 8,000 rpm for 5 min, in Table 1 Composition of the CRM formulations Component
CRM Na-CMC Poloxamer PVP HP-β-CD Piperine Milk
Quantity (mg) AS
MS
NS
ASD
HIC
WP
MC
50 4 – – – – –
50 4 – – – – –
50 – 4 – – – –
50 – – 50 – – –
50 – – – 315 – –
50 4 – – – 4 –
50 – – – – – 4,000
CRM curcumin, Na-CMC sodium carboxymethyl cellulose, PVP polyvinylpyrrolidone, HP-β-CD hydroxypropyl-β-cyclodextrin, AS aqueous suspension, MS micronized suspension, NS nanosuspension, ASD amorphous solid dispersion, HIC HP-β-CD inclusion complex, WP with piperine, MC milk composite
324
an ice bath. In the second step, the chilled formulation (temperature0.9921 (
