The preparation of lipid-based drug delivery system using melt extrusion

Chitosan/bovine serum albumin layer-by-layer assembled particles for non-invasive inhaled drug delivery to the lungs

Layer-by-Layer (LbL) assembly of polyelectrolytes on a solid core particle is a well-established technique used to deliver drugs, proteins, regenerative medicines, combinatorial therapy, etc. It is a multifunctional delivery system which can be engineered using various core template particles and coating polymers. This study reports the development and in-vitro evaluation of LbL assembled particles for non-invasive inhaled delivery to the lungs. The LbL assembled particles were prepared by successively coating polyelectrolyte macromolecules, glycol chitosan and bovine serum albumin on 0.5- and 4.5-μm polystyrene particles. The LbL assembly of polyelectrolytes was confirmed by reversible change in zeta potential and sequential increase in the particle size after accumulation of the layer. The prepared LbL particles were further assessed for aerodynamic properties using two distinct nebulizers, and toxicity assessment in normal lung cells. The in-vitro aerosolization study performed using next generation impactor coupled with Pari LC Plus and Aeroeclipse nebulizer showed that both the LbL assembled 0.5 and 4.5-μm particles had MMAD <5 μm confirming suitable aerodynamic properties for non-invasive lung delivery. The in-vitro cytotoxicity, and TEER integrity following treatment with the LbL assembled particles in normal lung epithelial and fibroblasts showed no significant cytotoxicity rendering the LbL assembled particles safe. This study extends the efficiency of LbL assembled particles for novel applications towards delivery of small and large molecules into the lungs.

Scalable Production and In Vitro Efficacy of Inhaled Erlotinib Nanoemulsion for Enhanced Efficacy in Non-Small Cell Lung Cancer (NSCLC)

Non-small cell lung cancer (NSCLC) is a global concern as one of the leading causes of cancer deaths. The treatment options for NSCLC are limited to systemic chemotherapy, administered either orally or intravenously, with no local chemotherapies to target NSCLC. In this study, we have prepared nanoemulsions of tyrosine kinase inhibitor (TKI), erlotinib, using the single step, continuous manufacturing, and easily scalable hot melt extrusion (HME) technique without additional size reduction step. The formulated nanoemulsions were optimized and evaluated for their physiochemical properties, in vitro aerosol deposition behavior, and therapeutic activity against NSCLC cell lines both in vitro and ex vivo. The optimized nanoemulsion showed suitable aerosolization characteristics for deep lung deposition. The in vitro anti-cancer activity was tested against the NSCLC A549 cell line which exhibited 2.8-fold lower IC₅₀ for erlotinib-loaded nanoemulsion, as compared to erlotinib-free solution. Furthermore, ex vivo studies using a 3D spheroid model also revealed higher efficacy of erlotinib-loaded nanoemulsion against NSCLC. Hence, inhalable nanoemulsion can be considered as a potential therapeutic approach for the local lung delivery of erlotinib to NSCLC.

Hydrophobic ion pairing-based self-emulsifying drug delivery systems: a new strategy for improving the therapeutic efficacy of water-soluble drugs

INTRODUCTION

Self-emulsifying drug delivery systems (SEDDS) are formulations consisting of oil phase, emulsifiers, and co-emulsifiers, which can be spontaneously emulsified in the body to form O/W microemulsion. Traditionally, SEDDS are used commercially for the improvement of oral absorption and in vivo performances for poorly water-soluble drugs. However, SEDDS formulations were rarely reported for the delivery of water-soluble drugs. Recent studies have found that SEDDS have the potential for water-soluble macromolecular drugs by the application of the hydrophobic ion pairing (HIP) technology.

AREAS COVERED

This review summarized the characteristics of HIP complexes in SEDDS and introduced their advantages and discussed the future prospects of HIP-based SEDDS in drug delivery.

EXPERT OPINION

Hydrophobic ion pairing (HIP) is a technology that combines lipophilic structures on polar counterions to increase the lipophilicity through electrostatic interaction. Recent studies showed that HIP-based SEDDS offer an effective way to increase the mucosal permeability and improve the chemical stability for antibiotics, proteases, DNA-based drugs, and other water-soluble macromolecular drugs. It is believed that HIP-based SEDDS offer a potential and attractive method capable of delivering hydrophilic macromolecules with ionizable groups for oral administration.

Anticancer Applications of Essential Oils Formulated into Lipid-Based Delivery Nanosystems

The use of natural compounds is becoming increasingly popular among patients, and there is a renewed interest among scientists in nature-based bioactive agents. Traditionally, herbal drugs can be taken directly in the form of teas/decoctions/infusions or as standardized extracts. However, the disadvantages of natural compounds, especially essential oils, are their instability, limited bioavailability, volatility, and often irritant/allergenic potential. However, these active substances can be stabilized by encapsulation and administered in the form of nanoparticles. This brief overview summarizes the latest results of the application of nanoemulsions, liposomes, solid lipid nanoparticles, and nanostructured lipid carriers used as drug delivery systems of herbal essential oils or used directly for their individual secondary metabolites applicable in cancer therapy. Although the discussed bioactive agents are not typical compounds used as anticancer agents, after inclusion into the aforesaid formulations improving their stability and bioavailability and/or therapeutic profile, they indicated anti-tumor activity and became interesting agents with cancer treatment potential. In addition, co-encapsulation of essential oils with synthetic anticancer drugs into nanoformulations with the aim to achieve synergistic effect in chemotherapy is discussed.

Design Optimization and Evaluation of Solid Lipid Nanoparticles of Azelnidipine for the treatment of Hypertension

BACKGROUND

Solid lipid nanoparticles (SLN) are the most promising lipid-based drug delivery utilized for enhancing the solubility, bioavailability, and therapeutic efficacy of poorly water-soluble molecules. Azelnidipine (AZN) is a calcium channel blocker widely recommended for the treatment of high blood pressure but its activity is restricted due to high lipophilicity and poor solubility in the GIT. The current research focused on the development of the SLN of AZN and thereby improving the absorption, bioavailability, and therapeutic efficacy in hypertension which is a leading cause of death worldwide. Recent patents on SLN was available as U.S. Patent,10,973,798B2, U.S. Patent 10,251,960B2, U.S. Patent 2021/0069121A1, U.S. Patent 2022/0151945A1.

METHODS

SLN was developed by hot melt emulsification and ultrasonication method using glyceryl monostearate (GMS) as solid lipid and Poloxamer 188 as a surfactant for the stabilization of colloidal dispersion.

RESULTS

Box-Behnken model was utilized which predicted 13 batches in which concentration of GMS (X1), Poloxamer 188 (X2) and sonication time (X3) were considered as independent parameters. The particle size (Y1) and entrapment efficiency (Y2) were dependable parameters and optimized batch F2 showed a particle size of 166.4 nm, polydispersity index of 0.40 and zeta potential of -13.7 mV. The entrapment efficiency was observed at 86.21 %. FTIR spectra confirm the identity and compatibility with the formulation components. The differential scanning calorimetry (DSC) confirmed the absence of melting point and interpreted that AZN was entirely incorporated in the lipid matrix and transformed from crystalline to amorphous form. The ANOVA for the particle size (p-value: 0.0203), % EE (p-value: 0.0271) was found significant. The in-vitro drug release showed a sustained release pattern for about 12 h. The AZN-loaded SLN was lyophilized and intended for oral delivery.

CONCLUSION

AZN-loaded SLN was developed by the hot melt emulsification method which accelerated the solubility and bioavailability and released in a sustained manner for treating hypertension.

Functional Excipients and Novel Drug Delivery Scenario in Self-nanoemulsifying Drug Delivery System: A Critical Note

Lipid-based formulations have emerged as prospective dosage forms for extracting the therapeutic effects of existing lipophilic compounds and novel chemical entities more efficiently. Compared to other excipients, lipids have the added benefit of enhancing the bioavailability of lipophilic and highly metabolizable drugs due to their unique physicochemical features and similarities to in vivo components. Furthermore, lipids can minimize the needed dose and even the toxicity of drugs with poor aqueous solubility when employed as the primary excipient. Hence, the aim of the present review is to highlight the functional behavior of lipid excipients used in SNEDD formulation along with the stability aspects of the formulation in vivo. Moreover, this review also covered the importance of SNEDDS in drug delivery, the therapeutic and manufacturing benefits of lipids as excipients, and the technological advances made so far to convert liquid to solid SNEDDS like melt granulation, adsorption on solid support, spray cooling, melt extrusion/ spheronization has also highlighted. The mechanistic understanding of SNEDD absorption in vivo is highly complex, which was discussed very critically in this review. An emphasis on their application and success on an industrial scale was presented, as supported by case studies and patent surveys.

Lipid-based solubilization technology via hot melt extrusion: promises and challenges

INTRODUCTION

Self-emulsifying drug delivery systems (SEDDS) are a promising strategy to improve the oral bioavailability of poorly water-soluble drugs (PWSD). The excipients of SEDDS enable permeation through the mucus and gastro-intestinal barrier, inhibiting efflux transporters (e.g. P-glycoprotein) of drugs. Poor drug loading capacity and formulation instability are the main setbacks of traditional SEDDS. The use of polymeric precipitation inhibitors was shown to create supersaturable SEDDS with increased drug payload, and their solidification can help to overcome the instability challenge. As an alternative to several existing SEDDS solidification technologies, hot melt extrusion (HME) holds the potential for lean and continuous manufacturing of supersaturable solid-SEDDS. Despite being ubiquitously applied in solid lipid and polymeric processing, HME has not yet been widely considered for the preparation of SEDDS.

AREAS COVERED

The review begins with the rationale why SEDDS as the preferred lipid-based delivery systems (LBDS) is suitable for the oral delivery of PWSD and discusses the common barriers to oral administration. The potential of LBDS to surmount them is discussed. SEDDS as the flagship of LBDS for PWSD is proposed with a special emphasis on solid-SEDDS. Finally, the opportunities and challenges of HME from the lipid-based excipient (LBE) processing and product performance standpoint are highlighted.

EXPERT OPINION

HME can be a continuous, solvent-free, cost-effective, and scalable technology for manufacturing solid supersaturable SEDDS. Several critical formulations and process parameters in successfully preparing SEDDS via HME are identified.

Recent Progress in Hot Melt Extrusion Technology in Pharmaceutical Dosage Form Design

BACKGROUND

The Hot Melt Extrusion (HME) technique has shown tremendous potential in transforming highly hydrophobic crystalline drug substances into amorphous solids without using solvents. This review explores in detail the general considerations involved in the process of HME, its applications and advances.

OBJECTIVE

The present review examines the physicochemical properties of polymers pertinent to the HME process. Theoretical approaches for the screening of polymers are highlighted as a part of successful HME processed drug products. The critical quality attributes associated with the process of HME are also discussed in this review. HME plays a significant role in the dosage form design, and the same has been mentioned with suitable examples. The role of HME in developing several sustained release formulations, films, and implants is described along with the research carried out in a similar domain.

METHODS

The method includes the collection of data from different search engines like PubMed, ScienceDirect, and SciFinder to get coverage of relevant literature for accumulating appropriate information regarding HME, its importance in pharmaceutical product development, and advanced applications.

RESULTS

HME is known to have advanced pharmaceutical applications in the domains related to 3D printing, nanotechnology, and PAT technology. HME-based technologies explored using Design-of- Experiments also lead to the systematic development of pharmaceutical formulations.

CONCLUSION

HME remains an adaptable and differentiated technique for overall formulation development.

Development and Characterization of Sustained-Released Donepezil Hydrochloride Solid Dispersions Using Hot Melt Extrusion Technology

The aim of this work was to develop the sustained release formulation of donepezil hydrochloride (DH) using the hot-melt extruded solid dispersion technique via the rational screening of hydrophobic carriers. Hydrophobic carriers with different physicochemical properties such as pH-independent swellability, low-permeability (Eudragit^® RS PO (E-RS)), pH-independent non-swellability (ethyl cellulose N7 (EC-N7)), and the presence of lipids (Compritol^® 888 ATO (C-888)) with or without pore-forming agents were used to achieve the sustained release profile of DH. Mannitol (MNT) was chosen as the temporary pore-forming agent. The thermal analysis showed that both the drug and C-888 preserved their crystallinity within a solid dispersion. During a dissolution test, MNT could generate pores, and the drug release rate was proportionally correlated to the MNT content. Tailoring of the ratio of C-888 and MNT in the formulations along with an appropriate extrusion temperature profile resulted in the modified release of DH, and a preferable release pattern was obtained under these conditions. C-888 was chosen for the further investigations to obtain tablets with a high integrity. The optimized tablets were compared to the marketed formulation of Aricept^® in terms of drug release profiles. The optimized formulation showed the stable and sustained release behavior of extended release profile, which was close to the release behavior of Aricept^® with good tablet characteristics. It was concluded that the hot-melt extrusion technique can be utilized for the manufacturing of DH sustained release tablets with improved tablet integrity and characteristics by co-processing the tablet excipient with DH/C-888.

Nanoindentation of Graphene/Phospholipid Nanocomposite: A Molecular Dynamics Study

Graphene and phospholipids are widely used in biosensing and drug delivery. This paper studies the mechanical and electronic properties of a composite based on two graphene flakes and dipalmitoylphosphatidylcholine (DPPC) phospholipid molecules located between them via combination of various mathematical modeling methods. Molecular dynamics simulation showed that an adhesion between bilayer graphene and DPCC increases during nanoindentation of the composite by a carbon nanotube (CNT). Herewith, the DPPC molecule located under a nanotip takes the form of graphene and is not destroyed. By the Mulliken procedure, it was shown that the phospholipid molecules act as a "buffer" of charge between two graphene sheets and CNT. The highest values of electron transfer in the graphene/DPPC system were observed at the lower indentation point, when the deflection reached its maximum value.