Design and evaluation of nanocomposite microparticles to enhance dissolution and oral bioavailability of andrographolide

The Fabrication, Drug Loading, and Release Behavior of Porous Mannitol

Porous materials are widely used as an effective strategy for the solubilization of insoluble drugs. In order to improve the solubility and bioavailability of low water-solubility drugs, it is necessary to prepare porous materials. Mannitol is one of the most popular excipients in food and drug formulations. In this study, porous mannitol was investigated as a drug carrier for low water solubility drugs. Its fabrication, drug loading, and drug release mechanisms were investigated. Porous mannitol was fabricated using the co-spray-antisolvent process and utilizing polyvinylpyrrolidone K30 (PVP K30) as the template agent. Porous mannitol particles were prepared by changing the proportion of the template agent, spraying the particles with mannitol, and eluting with ethanol in order to regulate their pore structure. In subsequent studies, porous mannitol morphology and characteristics were determined systematically. Furthermore, curcumin and ibuprofen, two poorly water-soluble drugs, were loaded into porous mannitol, and their release profiles were analyzed. The results of the study indicated that porous mannitol can be prepared using PVP K30 as a template and that the amount of template agent can be adjusted in order to control the structure of the porous mannitol. When the template agent was added in amounts of 1%, 3%, and 5%, the mannitol pore size increased by 167.80%, 95.16%, and 163.98%, respectively, compared to raw mannitol. Molecular docking revealed that mannitol and drugs are adsorbents and adhere to each other by force interaction. The cumulative dissolution of curcumin and ibuprofen-loaded porous mannitol reached 69% and 70%, respectively. The release mechanism of curcumin and ibuprofen from drug-loaded mannitol was suitable for the Korsmeyer-Peppas kinetic model. In summary, the co-spray-antisolvent method proved effective in fabricating porous materials rapidly, and porous mannitol had a remarkable effect on drug solubilization. The results obtained are conducive to the development of porous materials.

Technology Transfer of a Validated RP-HPLC Method for the Simultaneous Estimation of Andrographolide and Paclitaxel in Application to Pharmaceutical Nanoformulation

Many analytical methods are reported for simultaneous estimation of pharmaceutical dosages form. However, only a few are reproducible at an industrial scale. The proposed research aims to establish a technology transfer (TT) protocol between two laboratories (Lab-X, originator) with binary and (Lab-Y, receiver) with quaternary high-performance liquid chromatography (HPLC) system. Thus, utilizing reverse-phase HPLC (RP-HPLC), a robust, sensitive and repeatable analytical method has been developed, validated and TT between two laboratories for simultaneous estimation of Andrographolide (AG) and Paclitaxel (PTX). The method has been developed on a Phenomenex Luna C18 column (150 x 4.6, 5) sustained at 40°C and validated under the International Conference on Harmonisation (ICH) Q2 (R1) regulatory guideline and TT USP chapter 1224. The mobile phase consisted of MilliQ (pH = 3) and a combination of acetonitrile and methanol (1:1) in the ratio 50:50 with a flow rate of 0.45 mL/min, linear gradient elution in both labs. The AG and PTX were detected on the PDA detector at 224 and 227 nm wavelength with retention time of 4.5 ± 0.34 and 8.2 ± 0.02 min and limit of detection was found 0.028 ± 0.004 μg/mL, and 0.028 ± 0.0007 μg/mL, whereas limit of quantification as 0.086 ± 0.011 μg/mL and 0.088 ± 0.0014 μg/mL respectively in both labs. Throughout, this approach we have proved that proposed method is repeatable in both labs, and it can be used to quantify AG and PTX in developed pharmaceutical nano-formulations.

Fabrication of Stable Apigenin Nanosuspension with PEG 400 as Antisolvent for Enhancing the Solubility and Bioavailability

The purpose of this paper is to prepare a stable apigenin nanosuspension with a drug concentration of 1.11 mg/mL through green and efficient antisolvent method. Compared with the traditional preparation process that may use toxic reagents, in this study, a green and effective strategy was applied for the preparation of stable apigenin nanosuspension by using an antisolvent method with PEG 400 as antisolvent to improve the solubility and bioavailability. It was found that the particle size of apigenin nanosuspension was about 280 nm, and the solubility and dissolution of the nanosuspension were 33 and 3 times higher than that of the apigenin, respectively. Pharmacokinetic study showed that the C_max and AUC 0-8 h values of the nanosuspension in fasting rats achieved about 6- and 2.5-fold enhancement than that of the apigenin, respectively. Stability test showed that the apigenin nanosuspension could be stored stably for 12 months at 25℃. Taken together, the antisolvent method with PEG 400 was proven to be a green and effective method to prepare the stable nanosuspension of poorly soluble drugs.

Development of a Solid Dispersion of Nystatin with Maltodextrin as a Carrier Agent: Improvements in Antifungal Efficacy against Candida spp. Biofilm Infections

The aim of this study was to improve the treatment of Candida albicans biofilms through the use of nystatin solid dispersions developed using maltodextrins as a hyperosmotic carrier. Characterization studies by differential scanning calorimetry, X-ray diffraction, dissolution studies, and particle size analysis were performed to evaluate changes in nystatin crystallinity. Antifungal activity and anti-biofilm efficacy were assessed by microbiological techniques. The results for nystatin solid dispersions showed that the enhancement of antifungal activity may be related to the high proportions of maltodextrins. Anti-biofilm assays showed a significant reduction (more than 80%) on biofilm formation with SD-N:MD [1:6] compared to the nystatin reference suspension. The elaboration process and physicochemical properties of SD-N:MD [1:6] could be a promising strategy for treatment of Candida biofilms.

Ethnobotany, Pharmacological activities and Bioavailability studies of "King of Bitter" (Kalmegh): A Review (2010-2020)

BACKGROUND

Andrographis paniculata, commonly known as "Kalmegh", is an annual herbaceous plant from family Acanthaceae. The whole plant of A. paniculata has explored for multiple pharmacological activities and is scientifically recognized by in-vivo and in-vitro studies. Various biotechnologically engineered techniques have been explored to enhance the bioavailability of this plant.

OBJECTIVE

In this review, we aim to present comprehensive recent advances in the ethnopharmacology, phytochemistry, specific pharmacology, safety and toxicology and bioavailability of A. paniculata and its pure compounds. Possible directions for future research are also outlined in brief, which will encourage advance investigations on this plant.

METHODS

Information on the recent updates of the present review is collected from different electronic scientific databases such as Science Direct, PubMed, Scopus, and Google Scholar. All the composed information is classified into different sections according to the objective of the paper.

RESULTS

More than hundred research and review papers have been studied and incorporated in the present manuscript. After vast literature search of A. paniculata, we present a noteworthy report of various phytoconstituents present in plant, which are accountable for potential therapeutic properties of the plant. Forty-five of studied articles give general information about introduction, ethnobotany and traditional uses of the plant. Twenty-two papers enclosed information about the phytoconstituents present in different parts of A. paniculata and seventy-two papers briefly outlined the pharmacological activities like antioxidant, anti-dengue, anti-ulcerogenic, antifungal, some miscellaneous activities like activity against SARS-CoV-2, antidiarrhoeal. Nineteen studies highlighted the research work conducted by various researchers to increased bioavailability of A. paniculata and two studies reported the safety and toxicology of the plant.

CONCLUSION

This review incorporated the scientifically validated research work encompassing the ethnobotanical description of the subjected plant, phytochemical profile, various pharmacological activities, and recent approaches to enhance the bioavailability of active metabolites.

Investigation of 1,2-Dimyristoyl-sn-Glycero-3-Phosphoglycerol-Sodium (DMPG-Na) Lipid with Various Metal Cations in Nanocochleate Preformulation: Application for Andrographolide Oral Delivery in Cancer Therapy

This study aimed at carrying out a preformulation investigation of nanocochleates (NCs) and develop andrographolide-loaded nanocochleates. Preformulation study comprised of exploring the effect of trivalent and divalent ions on transition temperature (TT) of lipid (DMPG-Na), on particle size (PS), entrapment efficacy (EE), zeta potential (ZP) of NCs, and effect of NCs on change in lipid solubility post-NC formation. Further, the andrographolide-loaded nanocochleates made with CaCl₂ (ANDNCs) were characterized for ZP, PS, EE, X-ray powder diffraction (PXRD), differential scanning calorimetry (DSC), transition electron microscopy (TEM), in vitro release studies, in vitro anticancer potential on the cell line of human breast cancer (MCF-7), in vivo oral pharmacokinetic studies, and tissue distribution in female Wistar rats. Nanocochleates developed with CaCl₂ had a significant reduction in PS (1.78-fold) and ZP (1.38-fold), and elevation of EE (1.17-fold) as compared to AlCl₃ developed NCs. Trivalent ions demonstrated elevation of TT as compared to divalent ions. Spiral-shaped ANDNCs demonstrated ZP, PS, and EE of - 121.46 ± 15.12 mV, 360 ± 47 nm, and 68.12 ± 3.81% respectively. In vitro release study of ANDNCs showed a strong pH-dependent release profile due to hydrogen bonding between NCs and andrographolide (AND). Formulated ANDNCs demonstrated 26.99-fold decrease in IC50 value as compared to free AND. Additionally, the oral bioavailability of AND from ANDNCs improved by 1.81-fold as compared to free AND. Furthermore, ANDNCs showed minimum accumulation within the vital organs such as liver, kidney, and spleen. Briefly, the preformulation study laid a platform for better understanding the NCs and its components. Further, developed ANDNCs revealed superior physiochemical properties to be used as an alternative for a clinical setting.

Enhanced anti-hepatoma effect of a novel curcumin analog C086 via solid dispersion technology

The novel curcumin analog C086, previously identified as an oral novel heat shock protein 90 (Hsp90) inhibitor, was found to exhibit anti-hepatoma activity in vitro and in vivo. However, owing to its limited aqueous solubility, the usage of C086 in the clinical application was restricted. This research focused on the increase of the aqueous solubility and bioavailability of C086 via a solid dispersion preparation to improve its accumulation in the liver, which accordingly enhanced anti-hepatoma activity. C086-solid dispersion (C086-SD) was successfully prepared by using solvent evaporation technology. As compared with bulk compound, aqueous solubility obtained with the optimal formulation (C086/PVP k30:1/6 (w/w)) was increased by 1.741 million-fold, and in the following oral administration experiment, bioavailability was found to be improved by an approximately 28-fold relative to C086-Suspension and accumulate preferably in the liver. Accordingly, C086-SD exhibited stronger potent anti-proliferative effects against liver cancer cell line (i.e. HepG2) than pure C086. Moreover, C086-SD was found to have an enhanced anti-hepatoma effect using the orthotopic hepatocellular carcinoma xenograft in BALB/C nude mice. The results above suggested the potential application of C086-SD in the treatment of liver cancer.

Fabrication of ultra-small nanocrystals by formation of hydrogen bonds: In vitro and in vivo evaluation

Poor water solubility and low bioavailability hinder the clinical application of about 70% of newly synthesized compounds. Nanocrystal technology has become a preferred way to improve bioavailability by improving solubility. However, it remains challenging to produce nanocrystals with ultra-small particle sizes to further enhance the extent of bioavailability. Herein, we constructed ultra-small puerarin nanocrystals (Pue-NCs) (20-40 nm) via formation of hydrogen bond during HPH. We confirmed the formation of hydrogen bonds by ¹H NMR and FTIR, and observed the distribution of polymer chains by SEM and TEM. The absorption mechanisms were studied in Caco-2 cell monolayers, and the results showed that the major transport mechanism for puerarin was passive diffusion, meanwhile, for Pue-NCs, the passive transport and micropinocytosis-mediated endocytosis coexisted. The absolute bioavailability of Pue-NCs was 35.28%, which was 11.54 folds compared to that of puerarin. Therapeutic equivalence was demonstrated between Pue-NCs and puerarin injection at 50 mg/kg and 15 mg/kg, respectively, in isoproterenol-induced myocardial ischemia model. This study provides a novel strategy for preparing ultra-small nanocrystals by HPH to increase bioavailability of poorly soluble drugs.

Novel breviscapine nanocrystals modified by panax notoginseng saponins for enhancing bioavailability and synergistic anti-platelet aggregation effect

Breviscapine (BVP) is a flavonoid compound with strong neuroprotective and anti-platelet aggregation effect. The objective of this study is to design novel BVP nanocrystals modified by natural panax notoginseng saponins (PNS) for enhancing dissolution and anti-platelet aggregation effect of BVP. BVP nanocrystals modified by PNS (BVP-NC/PNS) were firstly prepared by coupling homogenization technology and freeze-drying technology, and BVP nanocrystals modified by RH40 (BVP-NC/RH40) as reference for comparison. The morphology, crystals characterization, dissolution behavior and anti-platelet aggregation effect of BVP-NC/PNS was systemically evaluated. The results demonstrated that the PNS could effectively maintain stability of BVP-NC at suspensions state dependent of its surface activity and the electrostatic repulsion effect. Combination of PNS and trehalose could prevent the aggregation of BVP-NC/PNS during freeze-drying. The PXRD and DSC results demonstrated that the BVP crystal state in BVP-NC/PNS was not changed owing to PNS modification and homogenization treatment. And the freeze-dried BVP-NC could easily recover back to BVP-NS and significantly improve the dissolution of BVP. The AUC_(0-∞) of the BVP-NC/PNS was 4.54 times as high as that of the coarse BVP, but not significantly different compared to that of BVP-NC/RH40 (p < 0.05). The anti-platelet aggregation results demonstrated that, BVP-NC/PNS group showed more effective inhibition on PAF-induced platelet aggregation compared with corresponding control groups, which might attribute to the enhanced bioavailability of BVP and synergistic effect of PNS with BVP. In conclusion, PNS could be used as an alternative stabilizer for preparation of BVP-NC, and BVP-NC modified by PNS is a promising formulation strategy for enhancing oral bioavailability and anti-platelet aggregation of BVP.

The Shielding Effect of Microcrystalline Cellulose on Drug Nanocrystal Particles During Compaction

To elucidate the compaction behavior of drug nanocrystals based composite particles (NP) during tabletting, the compaction behavior of binary mixtures of microcrystalline cellulose (MCC) and nanocrystal particles was investigated. The force-displacement correlation of mixtures containing different ratios of MCC and micronized NP was studied in order to explain the nature on densification of NP during compaction, and the resultant compaction curves (pressure as function of in-die thickness) were systemically analyzed to elucidate the most important mechanisms of volume reduction for MCC and NP in different stages of compaction. The results showed that the close compaction of individual MCC was relatively quickly achieved, and the drug NP particles could slide into the intrinsic void spaces between MCC microparticles. This was the reason that the particles size of MCC used in this study was significantly larger compared to that of drug NP. This interstitial rearrangement phenomenon of NP occurred on a typical time scale and was strongly dependent on the speed of compaction. This migration behavior occurred on void spaces of MCC inter-particles might be identified as an elastic stress relaxation mechanism and be helpful to dissolution of NP. MCC can effectively shield the NP from significant aggregation during compaction process.