Maximizing the encapsulation efficiency and the bioavailability of controlled-release cetirizine microspheres using Draper-Lin small composite design

Encapsulation of conjugated linoleic acid and ruminant trans fatty acids to study the prevention of metabolic syndrome-a review

Studies have reported the potential benefits of consuming conjugated linoleic acid (CLA) and ruminant trans fatty acids (R-TFAs) in reducing the risk factors of metabolic syndrome (MetS). In addition, encapsulation of CLA and R-TFAs may improve their oral delivery and further decrease the risk factors of MetS. The objectives of this review were (1) to discuss the advantages of encapsulation; (2) to compare the materials and techniques used for encapsulating CLA and R-TFAs; and (3) to review the effects of encapsulated vs non-encapsulated CLA and R-TFAs on MetS risk factors. Examination of papers citing micro- and nano-encapsulation methods used in food sciences, as well as the effects of encapsulated vs non-encapsulated CLA and R-TFAs, was conducted using the PubMed database. A total of 84 papers were examined; of these, 18 studies were selected that contained information on the effects of encapsulated CLA and R-TFAs. The 18 studies that described encapsulation of CLA or R-TFAs indicated that micro- or nano-encapsulation processes stabilized CLA and prevented oxidation. CLA was mainly encapsulated using carbohydrates or proteins. So far, oil-in-water emulsification followed by spray-drying were the frequently used techniques for encapsulation of CLA. Further, 4 studies investigated the effects of encapsulated CLA on MetS risk factors compared with non-encapsulated CLA. A limited number of studies investigated the encapsulation of R-TFAs. The effects of encapsulated CLA or R-TFAs on the risk factors for MetS remain understudied; thus, additional studies comparing the effects of encapsulated and non-encapsulated CLA or R-TFAs are needed.

Doxorubicin-sanguinarine nanoparticles: formulation and evaluation of breast cancer cell apoptosis and cell cycle

BACKGROUND

Therapeutic resistance fails cancer treatment. Drug-nanoparticle combinations overcome resistance. Sanguinarine-conjugated nanoparticles may boost sanguinarine's anticancer effects.

METHODS

Sanguinarine, HPMC-NPs, and doxorubicin were tested on Adriamycin-resistant MCF-7/ADR breast cancer cells, parent-sensitive MCF-7, and MCR-5 normal cells (DX).

RESULTS

Regular distribution, 156 nm diameter, <1 μm average size, 100% intensity-SN is therapeutic. Furthermore, the obtained NPs showed PDI = 0.145, zeta-potential=-37.6, and EE%=90.5%. DX sensitized MCF-7 cells (IC50 = 1.4 μM) more than MCF-7/ADR cells (IC50 = 27 μM) with RR = 19.3. SA and SN were more toxic to MCF-7/ADR cells (overexpressed with P-gp) than their sensitive parent MCF-7 cells (IC50 = 4 μM, RR = 0.6 and 0.6 μM, RR = 0.7). MCR-5 normal lung cells were more resistant to SA (IC50 = 7.2 μM) and SN (IC50 = 1.6 μM) with a selection index > 2. Synergistic cytotoxic interactions reduced the IC50 from 27 μM to 1.6 (CI = 0.1) and 0.9 (CI = 0.4) after DX and nontoxic dosages (IC20) of SA and SN. DS and SN killed 27.1% and 39.4% more cells than DX (7.7%), SA (4.9%), SN (5.5%), or untreated control (0.3%). DS and DSN lowered CCND1 and survival in MCF-7/ADR cells while raising p21 and Casp3 gene and protein expression.

CONCLUSIONS

Cellular and molecular studies suggested adjuvant chemosensitizers SA and SN to reverse MDR in breast cancer cells.

Preparation, characterization and wound-healing effect of PEGylated nanoliposomes loaded with oleuropein

Chronic wounds have become a major concern for healthcare systems, as they have been related to diabetic foot ulcers, venous leg ulcers and pressure ulcers. Oleuropein is an active compound that is extracted from olive leaves and it has the ability to reduce injury to tissues owing to its antioxidant effect, hence improving wound healing. The poor pharmacokinetics of oleuropein have limited its use clinically. This work is aimed toward studying the impact of PEGylated and non-PEGylated nanoliposomes loaded with oleuropein, as a carrier model, on wound-healing activity. The thin film hydration method was used to compose PEGylated and non-PEGylated liposomes, both loaded with oleuropein. The results indicated that each free, PEGylated and non-PEGylated composition was within the limit of optimum nanoliposome characterization. The results showed that non-PEGylated compositions produced higher efficiency in encapsulation (47.09 ± 10.06%) than the PEGylated ones (20.97 ± 10.52%). The PEG-nanoliposomes loaded with oleuropein (PEG-oleu) had mean size, charge and polydispersity index of 129.35 nm, -9.55 mV and 0.1010, respectively. The scratch assay results proved that PEGylated liposomal compositions have a more rapid wound-healing activity than non-PEGylated ones at different time intervals at 0, 2, 24 and 28 h.

Fabrication of polyvinyl pyrrolidone-K90/Eudragit RL100-based dissolving microneedle patches loaded with alpha-arbutin and resveratrol for skin depigmentation

Alpha-arbutin (AA) and resveratrol (Res) are widely used in skin-lightening products. However, current topical formulations have minimal skin-lightening effects due to the low absorption and poor solubility of these active compounds. This study investigated the efficacy and safety of using dissolving microneedle (DMN) patches to improve the delivery of AA and Res for skin depigmentation. The DMN patches (F0-F3) fabricated from polyvinyl pyrrolidone-K90 (PVP-K90)/Eudragit RL100 blends successfully penetrated excised porcine skin and showed sufficient mechanical strength to resist compression forces. Loading DMNs with 10% AA and 2% Res at a ratio of 5 : 1 (F3) resulted in a synergistic interaction between the drugs with desirable dissolving ability, drug loading, and stability. Furthermore, both in vitro and in vivo studies revealed that the use of F3 DMN patches successfully enhanced the intradermal delivery of AA and Res over a 24 h period, with the delivered amount being higher (∼2.6 times) than that provided by a cream formulation (P < 0.05). After removing the DMN patches, the mice's skin was spontaneously and completely resealed within 12 h. In clinical studies, F3 DMN patches slightly decreased the melanin index of the participants without causing skin irritation or erythema at any time during the 24 h period when the patches were applied (P < 0.05). Moreover, application of the patches for 24 h was not found to affect skin hydration, transepidermal water loss, or skin elasticity. Therefore, AA/Res-loaded DMN patches could offer a promising approach for the effective local delivery of cosmetic agents for skin depigmentation.

k-Carrageenan/sericin-based multiparticulate systems: A novel gastro-resistant polymer matrix for indomethacin delivery

This study aimed to develop a natural and multiparticulate carrier of k-carrageenan (k-Car) and sericin (Ser) for encapsulation of indomethacin (IND) in order to minimize gastrointestinal effects caused by immediate-release. Increasing the amount of IND in the formulations subtly reduced the entrapment efficiency (EE) and drug loading (DL) due to matrix saturation. Sericin was essential to improve EE and DL when compared to pure k-Car (EE > 90 % and DL > 47 %) with suitable particle sizes (1.3461 ± 0.1891-1.7213 ± 0.1586 mm). The incorporation and integrity of IND in the particles were confirmed by analytical techniques of HPLC, XRD, FTIR, and SEM. Additionally, the k-Car/Ser matrix was pH-responsive with low IND release at pH 1.2 and extended-release at pH 6.8. The Weibull model had an adequate fit to the experimental data with R²aju 0.950.99 and AIC 82.4-24.9, with curves in parabolic profile (b < 1) and indicative of a controlled drug-release mechanism by diffusion. Besides, k-Car/Ser/IND and placebo were not cytotoxic (cell viability > 85 % at 150-600 μM) for the Caco-2 cell line. Therefore, the polymeric matrix is gastro-resistant, stable, and biocompatible to carry indomethacin and deliver it to the intestinal environment.

Green synthesis of hyaluronic acid coated, thiolated chitosan nanoparticles for CD44 targeted delivery and sustained release of Cisplatin in cervical carcinoma

Cervical carcinoma is one of the most prevalent gynecological cancers throughout the world. Cisplatin is used as first line chemotherapy for treatment of cervical cancer, but it comes with plethora of side effects. The aim of this study was to develop hyaluronic acid coated, thiolated chitosan nanocarriers using green synthesis approach, for CD44 targeted delivery and sustained release of Cisplatin in cervical cancer cells. After synthesis through ionic gelation method, Zeta analysis showed that the nanoparticle size was 265.9 nm with a zeta potential of +22.3 mV and .226 PDI. SEM and TEM analysis confirmed the spherical shape and smooth surface of nanoparticles. FTIR and XRD showed the presence of characteristic functional groups, successful encapsulation of drug, and crystalline nature of nanoparticles respectively. Drug loading and entrapment efficiency were calculated to be 70.1% ± 1.2% and 45% ± .28% respectively. Analysis of in vitro drug release kinetics showed that drug release followed the Higuchi model at pH 6.8 and 7.4 and Cisplatin release for up to 72 h confirmed sustained release. In vitro analysis on cervical cancer cells HeLa and normal cervical epithelial cells HCK1T was done through cell morphology analysis, trypan blue assay (concentration range of 10-80 μg/ml), and MTT cytotoxic assay (concentration range of 10-90 μg/ml). The results showed a higher cytotoxic potential of HA coated, thiolated chitosan encapsulated Cisplatin (HA-ThCs-Cis NP) nanoformulation as compared to pure Cisplatin in HeLa while in HCK1T, pure Cisplatin showed much higher toxicity as compared to HA-ThCs-Cis nanoformulation. These findings suggest that CD44 targeted delivery system can be a useful approach to minimize offtarget toxicities, give sustained release and better cellular uptake in cancer cells.

Mechanistic exploration of the activities of poly(lactic-co-glycolic acid)-loaded nanoparticles of betulinic acid against hepatocellular carcinoma at cellular and molecular levels

The effectiveness of betulinic acid (B) and PLGA loaded nanoparticles of B (Bnp) against hepatocellular carcinoma (HCC) was established and reported earlier. In continuation of our previous report, the present study described the molecular mechanisms of their antineoplastic responses. In this context, the antineoplastic properties of both B and Bnp were evaluated on DEN-induced HCC rat model. The quantitative real-time polymerase chain reaction and western blot analyses revealed that HCC was developed through lower expressions of e-NOS, BAX, BAD, Cyt C and higher expressions of i-NOS, Bcl-xl, Bcl-2. B and Bnp normalised the expressions of these apoptogenic markers. Particularly, both activated i-NOS and e-NOS mediated Bcl-2 family proteins→CytC→Caspase 3 and 9 signalling cascades. The ¹H-NMR-based metabolomics study also demonstrated that the perturbed metabolites in DEN-induced rat serum restored to the normal level following both treatments. Moreover, the antineoplastic potential of Bnp was found to be comparable with the marketed product, 5-flurouracil.

PEG-4000 formed polymeric nanoparticles loaded with cetuximab downregulate p21 &stathmin-1 gene expression in cancer cell lines

Cetuximab (CTX) is known to have cytotoxic effects on several human cancer cells in vitro; however, as CTX is poorly water soluble, there is a need for improved formulations can reach cancer cells at high concentrations with low side effects. We developed (PEG-4000) polymeric nanoparticles (PEGNPs) loaded with CTX and evaluated their in vitro cytotoxicity and anticancer properties against human lung (A549) and breast (MCF-7) cancer cells. CTX-PEGNPs were formulated using the solvent evaporation technique, and their morphological properties were evaluated. Further, the effects of CTX-PEGNPs on cell viability using the MTT assay and perform gene expression analysis, DNA fragmentation measurements, and the comet assay. CTX-PEGNP showed uniformly dispersed NPs of nano-size range (253.7 ± 0.3 nm), and low polydispersity index (0.16) indicating the stability and uniformity of NPs. Further, the zeta potential of the preparations was -17.0 ± 1.8 mv. DSC and FTIR confirmed the entrapping of CTX in NPs. The results showed IC₅₀ values of 2.26 μg/mL and 1.83 μg/mL for free CTX and CTX-PEGNPs on the A549 cancer cell line, respectively. Moreover, CTX-PEGNPs had a lower IC₅₀ of 1.12 μg/mL in MCF-7 cells than that of free CTX (2.28 μg/mL). The expression levels of p21 and stathmin-1 were significantly decreased in both cell lines treated with CTX-PEGNPs compared to CTX alone. The CTX-PEGNP-treated cells also showed increased DNA fragmentation rates in both cancer cell lines compared with CTX alone. The results indicated that CTX-PEGNP was an improved formulation than CTX alone to induce apoptosis and DNA damage and inhibit cell proliferation through the downregulation of P21 and stathmin-1 expression.

The Hitchhiker's Guide to Human Therapeutic Nanoparticle Development

Nanomedicine plays an essential role in developing new therapies through novel drug delivery systems, diagnostic and imaging systems, vaccine development, antibacterial tools, and high-throughput screening. One of the most promising drug delivery systems are nanoparticles, which can be designed with various compositions, sizes, shapes, and surface modifications. These nanosystems have improved therapeutic profiles, increased bioavailability, and reduced the toxicity of the product they carry. However, the clinical translation of nanomedicines requires a thorough understanding of their properties to avoid problems with the most questioned aspect of nanosystems: safety. The particular physicochemical properties of nano-drugs lead to the need for additional safety, quality, and efficacy testing. Consequently, challenges arise during the physicochemical characterization, the production process, in vitro characterization, in vivo characterization, and the clinical stages of development of these biopharmaceuticals. The lack of a specific regulatory framework for nanoformulations has caused significant gaps in the requirements needed to be successful during their approval, especially with tests that demonstrate their safety and efficacy. Researchers face many difficulties in establishing evidence to extrapolate results from one level of development to another, for example, from an in vitro demonstration phase to an in vivo demonstration phase. Additional guidance is required to cover the particularities of this type of product, as some challenges in the regulatory framework do not allow for an accurate assessment of NPs with sufficient evidence of clinical success. This work aims to identify current regulatory issues during the implementation of nanoparticle assays and describe the major challenges that researchers have faced when exposing a new formulation. We further reflect on the current regulatory standards required for the approval of these biopharmaceuticals and the requirements demanded by the regulatory agencies. Our work will provide helpful information to improve the success of nanomedicines by compiling the challenges described in the literature that support the development of this novel encapsulation system. We propose a step-by-step approach through the different stages of the development of nanoformulations, from their design to the clinical stage, exemplifying the different challenges and the measures taken by the regulatory agencies to respond to these challenges.

Physicochemical properties of heterogeneously acetylated glucomannan of A. oncophyllus and its performance for iron encapsulation

Abstract Well-known as a food additive, glucomannan has excellent biocompatibility and biodegradability properties. However, glucomannan is easily gelled, which limited its use in high concentration. To reduce the gel formation ability of glucomannan, acetylation was conducted. This work aims to study the effect of acetylation on physicochemical properties of glucomannan. Acetylation was performed in heterogeneous system which glucomannan was immersed in ethanol (96%) with various concentrations of glucomannan (5-25%) and acetic acid (5-99%). This modified glucomannan was subsequently used as an encapsulation matrix for producing iron beads. The results showed that higher concentration of acetic acid in acetylation impacted on higher solubility and viscosity of glucomannan. The transmittance intensity of Infrared (IR) spectra and morphology of glucomannan were changed due to the acetylation and encapsulation process. The highest viscosity of the matrix (484.33 cP) led to the highest Encapsulation Yield (EY) (53.3%). Gompertz’s model fitted to describe the release profile of iron in all samples (R2>0.92) that showed the burst phenomena in the initial release. This work found that acetylated glucomannan had higher solubility and has a potency to protect the iron taste during oral consumption as it releases slower in neutral pH solution.

Superfast Synthesis of Stabilized Silver Nanoparticles Using Aqueous Allium sativum (Garlic) Extract and Isoniazid Hydrazide Conjugates: Molecular Docking and In-Vitro Characterizations

Green synthesis of silver nanoparticles (AgNPs) was synthesized from fresh garlic extract coupled with isoniazid hydrazide (INH), a commonly used antibiotic to treat tuberculosis. A molecular docking study conducted with the selected compounds compared with anthranilate phosphoribosyltransferase (trpD) from Mycobacterium tuberculosis. The aqueous extract of garlic was prepared and mixed with silver nitrate (AgNO3) solution for the superfast synthesis of stable AgNPs. INH was then conjugated with AgNPs at different ratios (v/v) to obtain stable INH-AgNPs conjugates (AgNCs). The resulting AgNCs characterized by FTIR spectra revealed the ultrafast formation of AgNPs (<5 s) and perfectly conjugated with INH. The shifting of λmax to longer wavelength, as found from UV spectral analysis, confirmed the formation of AgNCs, among which ideal formulations (F7, F10, and F13) have been pre-selected. The zeta particle size (PS) and the zeta potential (ZP) of AgNPs were found to be 145.3 ± 2.1 nm and −33.1 mV, respectively. These data were significantly different compared to that of AgNCs (160 ± 2.7 nm and −14.4 mV for F7; 208.9 ± 2.9 nm and −19.8 mV for F10; and 281.3 ± 3.6 nm and −19.5 mV for F13), most probably due to INH conjugation. The results of XRD, SEM and EDX confirmed the formation of AgNCs. From UV spectral analysis, EE of INH as 51.6 ± 5.21, 53.6 ± 6.88, and 70.01 ± 7.11 %, for F7, F10, and F13, respectively. The stability of the three formulations was confirmed in various physiological conditions. Drug was released in a sustainable fashion. Besides, from the preferred 23 compounds, five compounds namely Sativoside R2, Degalactotigonin, Proto-desgalactotigonin, Eruboside B and Sativoside R1 showed a better docking score than trpD, and therefore may help in promoting anti-tubercular activity.

Cholesterol-Based Nanovesicles Enhance the In Vitro Cytotoxicity, Ex Vivo Intestinal Absorption, and In Vivo Bioavailability of Flutamide

Critical adverse effects and frequent administration, three times per day, limit the use of flutamide (FLT) as a chemotherapeutic agent in the treatment of prostate cancer. Therefore, our research aimed to develop new cholesterol-based nanovesicles for delivering FLT to malignant cells in an endeavor to maximize its therapeutic efficacy and minimize undesired adverse effects. Draper–Lin small composite design was used to optimize the critical quality attributes of FLT-loaded niosomes and ensure the desired product quality. The influence of the selected four independent variables on mean particle size (Y₁), zeta potential (Y₂), drug entrapment efficiency (Y₃), and the cumulative drug release after 24 h (Y₄) was examined. The optimized nanovesicles were assessed for their in vitro cytotoxicity, ex-vivo absorption via freshly excised rabbit intestine as well as in vivo pharmacokinetics on male rats. TEM confirmed nanovescicles’ spherical shape with bilayer structure. Values of dependent variables were 748.6 nm, −48.60 mV, 72.8% and 72.2% for Y₁, Y₂, Y₃ and Y₄, respectively. The optimized FLT-loaded niosomes exerted high cytotoxic efficacy against human prostate cancer cell line (PC-3) with an IC₅₀ value of 0.64 ± 0.04 µg/mL whilst, it was 1.88 ± 0.16 µg/mL for free FLT. Moreover, the IC₅₀ values on breast cancer cell line (MCF-7) were 0.27 ± 0.07 µg/mL and 4.07 ± 0.74 µg/mL for FLT-loaded niosomes and free FLT, respectively. The permeation of the optimized FLT-loaded niosomes through the rabbit intestine showed an enhancement ratio of about 1.5 times that of the free FLT suspension. In vivo pharmacokinetic study displayed an improvement in oral bioavailability of the optimized niosomal formulation with AUC and C_max values of 741.583 ± 33.557 μg/mL × min and 6.950 ± 0.45 μg/mL compared to 364.536 ± 45.215 μg/mL × min and 2.650 ± 0.55 μg/mL for the oral FLT suspension. With these promising findings, we conclude that encapsulation of FLT in cholesterol-loaded nanovesicles enhanced its anticancer activity and oral bioavailability which endorse its use in the management of prostate cancer.

Synthesis and release behavior of layered double hydroxides-carbamazepine composites

Carbamazepine (CBZ) was incorporated into layered double hydroxides (LDH) to be used as a controlled drug system in solid tumors. CBZ has a formal charge of zero, so its incorporation in the anionic clay implies a challenge. Aiming to overcome this problem, CBZ was loaded into LDH with sodium cholate (SC), a surfactant with negative charge and, for comparison, without SC by the reconstruction method. Surprisingly, it was found that both resultant nanocomposites had similar CBZ encapsulation efficiency, around 75%, and the LDH-CBZ system without SC showed a better performance in relation to the release kinetics of CBZ in simulated body fluid (pH 7.4) and acetate buffer simulating the cellular cytoplasm (pH 4.8) than the system with SC. The CBZ dimensions were measured with Chem3D and, according to the basal spacing obtained from X-ray patterns, it can be arranged in the LDH-CBZ system as a monolayer with the long axis parallel to the LDH layers. Fourier transform infrared spectroscopy and solid state NMR measurements confirmed the presence of the drug, and thermogravimetric analyses showed an enhanced thermal stability for CBZ. These results have interesting implications since they increase the spectrum of LDH application as a controlled drug system to a large number of nonionic drugs, without the addition of other components.

Early administration of MPC-n(IVIg) selectively accumulates in ischemic areas to protect inflammation-induced brain damage from ischemic stroke

Ischemic stroke is an acute and severe neurological disease, which leads to disability and death. Immunomodulatory therapies exert multiple remarkable protective effects during ischemic stroke. However, patients suffering from ischemic stroke do not benefit from immunomodulatory therapies due to the presence of the blood-brain barrier (BBB) and their off-target effects. Methods: We presented a delivery strategy to optimize immunomodulatory therapies by facilitating BBB penetration and selectively delivering intravenous immunoglobulin (IVIg) to ischemic regions using 2-methacryloyloxyethyl phosphorylcholine (MPC)-nanocapsules, MPC-n(IVIg), synthesized using MPC monomers and ethylene glycol dimethyl acrylate (EGDMA) crosslinker via in situ polymerization. In vitro and in vivo experiments verify the effect and safety of MPC-n(IVIg). Results: MPC-n(IVIg) efficiently crosses the BBB and IVIg selectively accumulates in ischemic areas in a high-affinity choline transporter 1 (ChT1)-overexpression dependent manner via endothelial cells in ischemic areas. Moreover, earlier administration of MPC-n(IVIg) more efficiently deliver IVIg to ischemic areas. Furthermore, the early administration of low-dosage MPC-n(IVIg) decreases neurological deficits and mortality by suppressing stroke-induced inflammation in the middle cerebral artery occlusion model. Conclusion: Our findings indicate a promising strategy to efficiently deliver the therapeutics to the ischemic target brain tissue and lower the effective dose of therapeutic drugs for treating ischemic strokes.

QbD-Enabled Systematic Development of Ileo-colonic Targeted Novel Mucoadhesive Microspheres of Flurbiprofen

BACKGROUND

Flurbiprofen (FLBP) is used in the treatment of ulcerative colitis and has a short biological half-life. Frequent intake of FLBP may lead to some serious gastric complications, which makes FLBP an ideal candidate for sustained release preparation to the Ileo-colonic region of the gastrointestinal tract (GIT).

OBJECTIVE

The objective of this study was to investigate the potential of Eudragit coated chitosan microspheres in delivering Flurbiprofen in a sustained manner to the Ileo-colonic region of the GIT for treatment of ulcerative colitis.

METHODS

In the present study, mucoadhesive chitosan microspheres were prepared using the emulsion solvent evaporation method by varying different process parameters. Optimized chitosan microspheres were coated with Eudragit L-100 and Eudragit S-100. A 32 full factorial design was applied for optimization. The effect of independent variables (Eudragit L-100 to Eudragit S-100 ratio and stirring speed) on the dependent variable, i.e., percentage cumulative drug release (%CDR) at 3 h and 24 h was evaluated. The optimized batch was evaluated by FT-IR, DSC study, XRD study, and SEM analysis.

RESULTS

Discrete spherical shape chitosan microspheres with entrapment efficiency of up to 95.4% were obtained and selected for coating. Chitosan microspheres coated successfully with different ratios of Eudragit L-100 to Eudragit S-100. The release profile of the optimized batch match with the desired release profile. FLBP was found to be stable and molecularly dispersed in the polymer matrix.

CONCLUSION

Taken together, it can be concluded that prepared microspheres may be considered suitable for delivering FLBP to the Ileo-colonic region of the GIT in the treatment of ulcerative colitis.

Evaluation of Drug-Loading Ability of Poly(Lactic Acid)/Hydroxyapatite Core-Shell Particles

Poly(lactic acid)/hydroxyapatite (PLA/HAp) core-shell particles are prepared using the emulsification method. These particles are safe for living organisms because they are composed of biodegradable polymers and biocompatible ceramics. These particles are approximately 50-100 nm in size, and their hydrophobic substance loading can be controlled. Hence, PLA/HAp core-shell particles are expected to be used as drug delivery carriers for hydrophobic drugs. In this work, PLA/HAp core-shell particles with a loading of vitamin K1 were prepared, and their drug-loading ability was evaluated. The particles were 40-80 nm in diameter with a PLA core and a HAp shell. The particle size increased with an increase in the vitamin K1 loading. The drug-loading capacity (LC) value of the particles, an indicator of their drug-loading ability, was approximately 250%, which is higher than the previously reported values. The amount of vitamin K1 released from the particles increased as the pH of the soaking solution decreased because the HAp shell easily dissolved under the acidic conditions. The PLA/HAp particles prepared in this work were found to be promising candidates for drug delivery carriers because of their excellent drug-loading ability and pH sensitivity.

Pulmonary drug delivery with aerogels: engineering of alginate and alginate-hyaluronic acid microspheres

In this study, the aerogel technology was used to prepare pulmonary drug carriers consisting of alginate and alginate-hyaluronic acid by an emulsion gelation technique and supercritical CO₂ drying. During the preparation process, the emulsification rate and inner phase viscosity were varied to control the diameter of aerogel microspheres. Results showed that the aerogel microspheres were highly porous (porosity > 98%) with low densities in the range between 0.0087 and 0.0634 g/cm³ as well as high surface areas between 354 and 759 m²/g. The obtained microspheres showed aerodynamic diameter below 5 µm making them suitable for pulmonary drug delivery. An in vitro drug release study with the model drug sodium naproxen was conducted and a non-Fickian drug release mechanism was observed, with no significant difference between the release profiles of alginate and alginate-hyaluronic acid microspheres. During the emulsion gelation step, the feasibility of using the capillary number to estimate the largest stable droplet size in the emulsions was also studied and it was found that using this number, the droplet size in the emulsions may well be predicted.

Development and in vitro evaluation of microparticles of fluoxetine in galactomannan against biofilms of S. aureus methicilin resistant

The emergence of multidrug-resistant (MDR) bacteria is a global problem, by reducing the effectiveness of traditional antibiotics and decreasing the therapeutic arsenal to treat bacterial infections. This has led to an increase in researches about how to overcome this resistance to antibiotics. One strategy is the repositioning (or repurposing) of existing drugs not previously used to combat microorganisms, rather than the development of new drugs. Fluoxetine (FLX) is a selective serotonin reuptake inhibitor (SSRIs) and is considered one of the first highly selective antidepressants of the monoamine neurotransmitter serotonin (5-HT). The objective of this study is to prepare and physically characterize fluoxetine microparticles with galactomannan and evaluate their efficacy against strains of Staphylococcus aureus sensitive and resistant to methicillin. The microparticles were analyzed by differential scanning calorimetry (DSC), infrared analysis (IR) and X-ray diffraction (XRD). In addition, the percentage of encapsulation efficiency (EE%) and drug release kinetics were determined in vitro, along with the determination of the minimum inhibitory concentration (MIC) and evaluation of the action against biofilms. Physical tests were conducted to characterize galactomannan (GAL), FLX, oxacillin (OXA) and the galactomannan/fluoxetine microparticles (GFM). The EE% value was 98 % and, in regard the release, tests with the microparticles released about 60 % of the drug in 200 min. The isolated MIC results for FLX (255 μg/mL) and OXA MIC (1.97-15.62 μg/mL) showed that the strains were resistant. Furthermore, in the biofilms, microparticles showed statically significant improvement for all concentrations used. The study revealed that fluoxetine encapsulated in microparticles has the potential to act as an effective antimicrobial agent.

Preparation of internally-crosslinked alginate microspheres: Optimization of process parameters and study of pH-responsive behaviors

In this study, the effects of various parameters of the water-in-oil emulsification/internal gelation method on the properties of calcium-alginate microparticles were evaluated and optimized. Results showed that the spherical-shaped microparticles with the highest circularity and high production yield can be produced by alginate solution with a concentration of 2 wt.%, calcium carbonate/alginate ratio of 10/1 (w/w), water/oil volume ratio of 1/20, emulsifier concentration of 5 % (v/v), and emulsification speed of 1000 rpm. Two model drugs including simvastatin lactone and simvastatin β-hydroxyacid were loaded into the microspheres with promising encapsulation efficiencies of 73 % and 69 %, respectively. The microspheres showed a pH-responsive swelling behavior with a percentage of 10.60 %, 352.65 %, 690.03 %, and 1211.46 % at the pH values of 2.0, 4.5, 7.4, and 8.5, respectively. The microspheres showed an increasing trend of release rate in direct proportion to pH. These findings would be useful for therapeutic applications which need pH-responsive drug carriers.

Extracellular Vesicles-Based Drug Delivery Systems: A New Challenge and the Exemplum of Malignant Pleural Mesothelioma

Research for the most selective drug delivery to tumors represents a fascinating key target in science. Alongside the artificial delivery systems identified in the last decades (e.g., liposomes), a family of natural extracellular vesicles (EVs) has gained increasing focus for their potential use in delivering anticancer compounds. EVs are released by all cell types to mediate cell-to-cell communication both at the paracrine and the systemic levels, suggesting a role for them as an ideal nano-delivery system. Malignant pleural mesothelioma (MPM) stands out among currently untreatable tumors, also due to the difficulties in achieving an early diagnosis. Thus, early diagnosis and treatment of MPM are both unmet clinical needs. This review looks at indirect and direct evidence that EVs may represent both a new tool for allowing an early diagnosis of MPM and a potential new delivery system for more efficient therapeutic strategies. Since MPM is a relatively rare malignant tumor and preclinical MPM models developed to date are very few and not reliable, this review will report data obtained in other tumor types, suggesting the potential use of EVs in mesothelioma patients as well.

Fabrication, characterization and comparison of α-arbutin loaded dissolving and hydrogel forming microneedles

In this study, polyacrylic acid-co-maleic acid (PAMA) and polyvinyl alcohol (PVA) (1:4) were used to fabricate dissolving microneedles (DMNs) and hydrogel forming microneedles (HMNs) which incorporated α-arbutin. Αlpha-arbutin is commonly used as a skin lightening agent. However, it has poor penetration ability due to its hydrophilic properties. The purpose of this study was to compare the permeation of α-arbutin into the skin using DMNs and HMNs. Both types of microneedles (MNs) were sharp, strong with elegant appearance and approximately 100% penetrated the neonatal porcine skin. All needles of α-arbutin loaded DMNs were completely dissolved within 45 min, whereas maximum swelling of HMNs was observed at 4 h. In vitro permeation studies showed that α-arbutin loaded DMNs and HMNs provided significantly about 4.5 and 2.8 times, respectively, greater α-arbutin permeability than gel and commercial cream (P < 0.05). In vivo study also showed high intradermal delivery of α-arbutin levels using DMNs (5.33 µg/mL) and HMNs (1.47 µg/mL) when compared to that of commercial cream 0.15 µg/mL. Moreover, the micro-holes caused by applying MNs can reseal within 1 h. MNs were also stable at 25 °C for 3 months. The results suggested that DMNs and HMNs developed have a promising platform for transdermal delivery.

Retinal photoreceptors targeting SA-g-AA coated multilamellar liposomes carrier system for cytotoxicity and cellular uptake evaluation

Here, the retinal targeting SA-g-AA coated multilamellar liposomes carrier synthesized to deliver the bioactive agents into the retinal region of the eye. The multilayered targeting macromolecules of liposomes prepared using a layer-by-layer assembly. The curcumin (CUR) and Rhodamine B (RhB) dyes loaded in a multilamellar vesicle (MLV) were synthesised by the lipid film hydration method. The sodium alginate grafted acrylic acid (SA-g-AA) conjugated with riboflavin (RB) was coated over MLV by O/W emulsion method followed by ionotropic gelation. FT-IR and ¹H NMR spectroscopy techniques used to analyse the structural features of the MLV-SA-g-AA-RB. The results of DLS and TEM revealed that the carrier could be of uniform spheres, with a low polydispersity index, and outstanding performance in phrases of dye encapsulation and extended-release ability. An MTT assay investigated cell viability against Fibroblast WS1, and human embryonic stem cells-derived retinal pigment epithelial cells (hESC-RPE) implied that the carrier is of excellent biocompatibility. Retina targeting nature of the system confirmed via cellular uptake results revealed that the increases the dye concentration in the cells. Overall, the outcomes suggested that carriers could lead to the improvement of a feasible two photoreceptors targeting drug carriers, and it has the potential to deliver the multidrug in the retinal region of the eye.

Design and Characterization of Spray-Dried Chitosan-Naltrexone Microspheres for Microneedle-Assisted Transdermal Delivery

Naltrexone (NTX) hydrochloride is a potent opioid antagonist with significant first-pass metabolism and notable untoward effects when administered orally or intramuscularly. Microneedle (MN)-assisted transdermal delivery is an attractive alternative that can improve therapeutic delivery to deeper skin layers. In this study, chitosan-NTX microspheres were developed via spray-drying, and their potential for transdermal NTX delivery in association with MN skin treatment was assessed. A quality-by-design approach was used to evaluate the impact of key input variables (chitosan molecular weight, concentration, chitosan-NTX ratio, and feed flow rate) on microsphere physical characteristics, encapsulation efficiency, and drug-loading capacity. Formulated microspheres had high encapsulation efficiencies (70%-87%), with drug-loading capacities ranging from 10%-43%. NTX flux through MN-treated skin was 11.6 ± 2.2 µg/cm²·h from chitosan-NTX microspheres, which was significantly higher than flux across intact skin. Combining MN-assisted delivery with the chitosan microsphere formulation enabled NTX delivery across the skin barrier, while controlling the dose released to the skin.

NIR-dye based mucoadhesive nanosystem for photothermal therapy in breast cancer cells

Breast cancer is one of the leading causes of mortality in women, worldwide. The average survival rate of patients suffering from advanced breast cancer is about 27% for five years. Photothermal therapy employing biodegradable nanoparticle are extensively researched for enhanced anticancer therapy in breast cancer treatment. In the current study, we report a chitosan based mucoadherant and biodegradable niosome nanoparticle entrapping near infrared (NIR) dye (IR 806) for the treatment of breast cancer. Niosome entrapping IR 806 (NioIR) showed encapsulation efficacy of about 56 ± 2%. The prepared nanoparticles (NioIR) were further coated with chitosan (NioIR-C) to impart mucoadhesive property to the nanosystem. NioIR-C showed minimal degradation following NIR laser irradiation, thus enhancing its photothermal stability. They also exhibited efficient photothermal transduction, when compared with IR 806 dye. NioIR-C were biocompatible when treated with normal cell lines (NIH 3T3 and L929) and showed cytotoxicity towards breast cancer cell lines (MCF-7 and MDA-MB 231). When triggered with NIR laser, NioIR-C showed photothermal cell death (approximately 93%). The presence of chitosan coating on NioIR led to mucoadherence potential that further enhances the therapeutic effect on breast cancer cells when compared with IR 806 dye and NioIR. Thus NioIR-C can be a promising nanosystem for effective treatment of breast cancer using photothermal therapy.

HPMC/PVP Dissolving Microneedles: a Promising Delivery Platform to Promote Trans-Epidermal Delivery of Alpha-Arbutin for Skin Lightening

Alpha-arbutin is one of the most efficient skin lightener agents, which shows the effect on reducing the pigmentation by competitively inhibiting human tyrosinase. However, alpha-arbutin has difficulty in skin permeability due to its hydrophilic property. The objective of this study was, therefore, to develop alpha-arbutin-loaded dissolving microneedles (DMNs) for improving the delivery of alpha-arbutin into the skin. The DMN patch was prepared using Gantrez™ S-97, hydroxypropyl methylcellulose (HPMC), polyvinylpyrrolidone K-90 (PVP), chitosan, and their combinations. The optimal 8% alpha-arbutin-loaded DMNs, aside from Gantrez™ S-97, was successfully formulated with combination of 8% w/w HPMC and 40% w/w PVP K-90 (HPMC/PVP) at the weight ratio of 1:1. Both DMNs had 100% of penetration into porcine skin. Over 12 h of skin permeation, the flux of Gantrez™ S-97 DMNs and the HPMC/PVP DMNs were 66.21 μg/cm²/h and 74.24 μg/cm²/h, respectively. The accumulation amount of alpha-arbutin in the skin from Gantrez™ S-97 DMNs and HPMC/PVP DMNs was 107.76 μg and 312.23 μg, respectively. In comparison to the gel formulations, Gantrez™ S-97 DMNs and HPMC/PVP DMNs increase the delivery of alpha-arbutin across the skin approximately 2 and 4.7 times, respectively. In vivo studies found that alpha-arbutin-loaded HPMC/PVP DMNs delivered more alpha-arbutin into the skin than commercial cream. Moreover, the skin can reseal naturally after removal of DMNs patch without any signs of infection and remain stable in accelerated conditions for 4 weeks. Accordingly, alpha-arbutin-loaded HPMC/PVP DMNs could be a promising delivery platform for promoting trans-epidermal delivery of alpha-arbutin for skin lightening.

Sustained release and pharmacologic evaluation of human glucagon-like peptide-1 and liraglutide from polymeric microparticles

The GLP1-receptor agonists exert regulatory key roles in diabetes, obesity and related complications. Here we aimed to develop polymeric microparticles loaded with homologous human GLP1 (7-37) or the analogue liraglutide. Peptide-loaded microparticles were prepared by a double emulsion and solvent evaporation process with a set of eight polymers based on lactide (PLA) or lactide-glycolide (PLGA), and evaluated for particle-size distribution, morphology, in vitro release and pharmacologic activity in mice. The resulting microparticles showed size distribution of about 30-50 μm. The in vitro kinetic release assays showed a sustained release of the peptides extending up to 30-40 days. In vivo evaluation in Swiss male mice revealed a similar extension of glycemic and body weight gain modulation for up to 25 days after a single subcutaneous administration of either hGLP1-microparticles or liraglutide-microparticles. Microparticles-loaded hGLP1 shows equivalent in vivo pharmacologic activity to the microparticles-loaded liraglutide.

Zein-alpha lipoic acid-loaded nanoparticles to enhance the oral bioavailability of dapoxetine: optimization and clinical pharmacokinetic evaluation

Background

Premature ejaculation (PE) is the most common type of male sexual disorder with important psychological consequences. Dapoxetine (DPX), a recently approved drug for the treatment of PE, suffers from low bioavailability with large variability that ranges from 15–76% (mean 42%) after oral administration. The objective of this study is to optimize the parameters for the preparation of DPX-Zein-alpha lipoic acid (ALA) nanoparticles (NPs) to improve the bioavailability of DPX and consequently decrease therapeutic dose and adverse effect, leading to patient satisfaction and compliance.

Methods

We investigated the effect of ALA concentration, PVA concentration and stirring rate on nanoparticle size (Y₁), zeta potential (Y₂), initial DPX release (Y₃) and cumulative DPX release (Y₄). In addition, in vivo pharmacokinetic study was performed for the optimized DPX formulation on human healthy volunteers compared with marketed DPX tablet.

Results

The optimized DPX-loaded NPs showed Y₁, Y₂, Y₃, and Y₄ of 159.24 nm, 19.14 mV, 25.31% and 95.9 %, respectively. A single oral dose of 30 mg of optimized DPX-loaded NPs to human volunteers resulted in 2-fold improvement of AUC (1376.145±339.592 vs 709.178±146.307 in DPX), 4-fold increase in t_max (2.5±0.314 vs 0.583±0.144), prolongation of MRT (7.637±1.373 compared to 6.031±1.826 h), but with reduction in t_1/2 (5.283±1.077 vs 8.452±2.813).

Conclusion

The clinical findings suggest 194% enhancement of relative bioavailability of the optimized DPX-loaded NPs, potentially leading to a decrease in therapeutic dose and associated side effects in the treatment of PE.

Microparticles, Microspheres, and Microcapsules for Advanced Drug Delivery

Microparticles, microspheres, and microcapsules are widely used constituents of multiparticulate drug delivery systems, offering both therapeutic and technological advantages. Microparticles are generally in the 1–1000 µm size range, serve as multiunit drug delivery systems with well-defined physiological and pharmacokinetic benefits in order to improve the effectiveness, tolerability, and patient compliance. This paper reviews their evolution, significance, and formulation factors (excipients and procedures), as well as their most important practical applications (inhaled insulin, liposomal preparations). The article presents the most important structures of microparticles (microspheres, microcapsules, coated pellets, etc.), interpreted with microscopic images too. The most significant production processes (spray drying, extrusion, coacervation, freeze-drying, microfluidics), the drug release mechanisms, and the commonly used excipients, the characterization, and the novel drug delivery systems (microbubbles, microsponges), as well as the preparations used in therapy are discussed in detail.

Preparation and Characterization of PLGA Nanoparticles Containing Plasmid DNA Encoding Human IFN-lambda-1/IL-29

During the 15 years since the discovery of type III human interferons [IFN-λ1(IL-29), IFN-λ2(IL-28A), and IFN-λ3(IL-28B)], numerous biological properties such as anticancer, antiviral, and immunomodulatory activities of this new IFN family have been investigated. Several studies have shown that the encapsulation of pcDNA with PLGA nanoparticles (NPs) protects them against DNase enzyme action and increases the efficiency of gene delivery to the cells. The purpose of this study was to encapsulate pcDNA encoding IFN-λ1 (pIFN-λ1) with a simple and cost-effective method using PLGA NPs. The pIFN-λ1-loaded PLGA NPs were produced by a double-emulsion-solvent evaporation method and characterized in terms of size, size distribution, and zeta potential by DLS and morphologically by SEM and TEM. The bioactivity of NPs was also examined by fluorescent microscopy. The results showed that IFN-λ1 expressed by HEK293T cells could protect HepC-2 cells from the cytopathic effects of EMCV. The NPs were spherical in shape with a mean diameter of 380 ± 3 nm, a zeta potential of -3.3 ± 7.6 mV, an encapsulation efficiency of 75 ± 5%, and a loading capacity of 0.83 ± 0.06. The NPs were also bioactive and easily engulfed by RAW264.7 cells. The pIFN-λ1 could be sustainably released from NPs. Due to the facility and affordability of encapsulation of pIFN-λ1 in the PLGA NPs proposed in this study and the advantages of encapsulation by PLGA, it appeared rational to use pIFN-λ1-loaded NPs instead of naked pIFN-λ1 to determine other unexplained activities of this new cytokine or to use it as an alternative or adjunct to current IFN-α therapy.

Poly(lactic-co-glycolic acid)-loaded nanoparticles of betulinic acid for improved treatment of hepatic cancer: characterization, in vitro and in vivo evaluations

PURPOSE

The application of betulinic acid (B), a potent antineoplastic agent, is limited due to poor bioavailability, short plasma half-life and inappropriate tissue distribution. Thus, we aimed to prepare novel 50:50 poly(lactic-co-glycolic acid) (PLGA)-loaded B nanoparticles (BNP) and to compare its anti-hepatocellular carcinoma (HCC) activity with parent B.

METHODS

BNP were synthesized and characterized using different methods such as scanning electron microscopy (SEM), fourier-transform infrared (FTIR) spectrometry and particle size analyses. Particle size of BNP was optimized through the application of the stabilizer, polyvinyl alcohol (PVA). The anti-HCC response was evaluated through in vitro cell line study using Hep-G2 cells, confocal microscopy, in vivo oral pharmacokinetics and animal studies. Further, quantitative reverse transcription polymerase chain reaction (qRT-PCR) analysis was conducted to observe the changes in the expression of specific genes.

RESULTS

Particle size of BNP was optimized through the application of the stabilizer, polyvinyl alcohol. Physicochemical characterization exhibited particle size of 257.1 nm with zeta potential -0.170 mV (optimized batch B, BNP). SEM and FTIR analyses of BNP showed that cylindrical particles of B converted to spherical particles in BNP and there were no interaction between B and used polymers. The release study of optimized BNP was highest (≥80%) than any other formulation. Later, in vitro cell culture analysis using Hep-G2 cells and confocal microscopy studies revealed that BNP had the highest inhibition and penetration properties than parent B. Oral pharmacokinetics studies using albino Wistar rats at single 100 mg dose again exhibited BNP had the higher 50% of plasma concentration (t1/2), a higher maximum plasma concentration (Cmax) and took longer to reach the maximum plasma concentration (Tmax) than parent B. Next, our in vivo study using nitrosodiethyl amine (NDEA)-induced HCC model documented BNP decreased in number of nodules, restored body weight, oxidative stress parameters, liver marker enzymes and histological architecture than parent B. Lastly, qRT-PCR studies further demonstrated that anti-HCC properties of BNP may be due to over expression of antiapoptotic caspases i.e., caspase 3 and 8.

CONCLUSION

The prepared BNP showed a better therapeutic response against HCC and could be attributed as future candidate molecule for HCC treatment.