Design,characterisation and drug release study of polymeric,drug‐eluting single layer thin films on the surface of intraocular lenses

To design, develop and study a novel drug delivery system for intraocular applications. The spin coating technique was applied to develop a polymeric, drug‐eluting thin film consisting of a blend of organic polymers [poly (D, L lactide coglycolide) lactide: glycolide 75: 25, PLGA and polycaprolactone, PCL] and dexamethasone on the surface of intraocular lenses (IOLs). The initial durability of the IOLs during spinning was assessed. Information about the structural and optical properties of the modified IOLs was extracted using atomic force microscopy, scanning electron microscopy and spectroscopic ellipsometry. A drug release study was conducted for 8 weeks. The IOLs were durable in spinning speeds higher than the ones used to develop thin films. Single‐layer thin films were successfully developed on the optics and the haptics of the lenses. The films formed nanopores with encapsulated aggregates of dexamethasone. The spectroscopic ellipsometry showed an acceptable optical transparency of the lenses regardless of the deposition of the drug‐eluting films on their surface. The drug release study demonstrated gradual dexamethasone release over the selected period. In conclusion, the novel drug‐eluting IOL system exhibited desired properties regarding its transparency and drug release rate. Further research is necessary to assess their suitability as an intraocular drug delivery system.Inspec keywords: ellipsometry, encapsulation, nanoporous materials, spin coating, polymer blends, biodegradable materials, surface treatment, polymer films, atomic force microscopy, transparency, nanomedicine, durability, scanning electron microscopy, drug delivery systemsOther keywords: drug release, intraocular lenses, intraocular applications, spin coating technique, modified IOLs, spectroscopic ellipsometry, dexamethasone release, transparency, drug release rate, intraocular drug delivery system, drug‐eluting IOL system, polymeric drug‐eluting single‐layer thin films, optical properties, structural properties     

Enhanced efficacy of clindamycin hydrochloride encapsulated in PLA/PLGA based nanoparticle system for oral delivery

Clindamycin hydrochloride (CLH) is a clinically important oral antibiotic with wide spectrum of antimicrobial activity that includes gram‐positive aerobes (staphylococci, streptococci etc.), most anaerobic bacteria, Chlamydia and certain protozoa. The current study was focused to develop a stabilised clindamycin encapsulated poly lactic acid (PLA)/poly (D,L‐lactide‐co‐glycolide) (PLGA) nano‐formulation with better drug bioavailability at molecular level. Various nanoparticle (NPs) formulations of PLA and PLGA loaded with CLH were prepared by solvent evaporation method varying drug: polymer concentration (1:20, 1:10 and 1:5) and characterised (size, encapsulation efficiency, drug loading, scanning electron microscope, differential scanning calorimetry [DSC] and Fourier transform infrared [FTIR] studies). The ratio 1:10 was found to be optimal for a monodispersed and stable nano formulation for both the polymers. NP formulations demonstrated a significant controlled release profile extended up to 144 h (both CLH‐PLA and CLH‐PLGA). The thermal behaviour (DSC) studies confirmed the molecular dispersion of the drug within the system. The FTIR studies revealed the intactness as well as unaltered structure of drug. The CLH‐PLA NPs showed enhanced antimicrobial activity against two pathogenic bacteria Streptococcus faecalis and Bacillus cereus. The results notably suggest that encapsulation of CLH into PLA/PLGA significantly increases the bioavailability of the drug and due to this enhanced drug activity; it can be widely applied for number of therapies.Inspec keywords: drug delivery systems, biomedical materials, antibacterial activity, nanoparticles, nanomedicine, microorganisms, polymers, nanofabrication, differential scanning calorimetry, encapsulation, drugs, scanning electron microscopy, Fourier transform infrared spectraOther keywords: Streptococcus faecalis, Bacillus cereus, DSC, stable nanoformulation, monodispersed nanoformulation, pathogenic bacteria, FTIR spectra, molecular dispersion, thermal behaviour, controlled release profile, Fourier transform infrared spectra, differential scanning calorimetry, scanning electron microscopy, drug loading, encapsulation efficiency, polymer concentration, solvent evaporation method, molecular level, drug bioavailability, stabilised clindamycin encapsulated poly lactic acid‐poly (D,L‐lactide‐co‐glycolide) nanoformulation, protozoa, Chlamydia, anaerobic bacteria, gram‐positive aerobes, antimicrobial activity, oral antibiotics, oral delivery, PLA‐PLGA based nanoparticle system, clindamycin hydrochloride     

Sialic acid‐conjugated PLGA nanoparticles enhance the protective effect of lycopene in chemotherapeutic drug‐induced kidney injury

Lycopene (LYC) is known to protect cells from oxidative damage caused by free radicals in human tissues. In the present study, the authors designed a LYC‐loaded sialic acid (SA)‐conjugated poly(D,L‐lactide‐co‐glycolide) (PLGA) nanoparticle (LYC‐NP) to enhance the therapeutic efficacy of LYC in acute kidney injury. The characteristics of the LYC‐NPs were defined according to particle size, morphology, and in vitro drug release. The LYC‐NPs exhibited a controlled release of LYC over 48 h. Confocal laser scanning microscopy clearly highlighted the targeting potential of SA. Enhanced green fluorescence was observed for the LYC‐NPs in H₂ O₂ ‐treated human umbilical vein endothelial cells, indicating enhanced internalisation of NPs. The LYC‐NPs showed significantly greater cell viability than H₂ O₂ ‐treated cells. In addition, the LYC‐NPs remarkably reduced proinflammatory cytokine levels, attributable mainly to the increased cellular internalisation of the SA‐based carrier delivery system. Furthermore, protein levels of caspase‐3 and ‐9 were significantly down‐regulated after treatment with the LYC‐NPs. Overall, they have demonstrated that SA‐conjugated PLGA‐NPs containing LYC could be used to treat kidney injury.Inspec keywords: fluorescence, biomedical materials, biological tissues, cellular biophysics, drugs, proteins, molecular biophysics, injuries, drug delivery systems, kidney, nanomedicine, biochemistry, optical microscopy, nanoparticles, nanofabrication, cancer, toxicology, blood vessels, particle sizeOther keywords: sialic acid‐conjugated PLGA nanoparticles, chemotherapeutic drug‐induced kidney injury, LYC‐NP, LYC‐loaded sialic acid‐conjugated poly(D,L‐lactide‐co‐glycolide) nanoparticle, SA‐conjugated PLGA‐NP, protective effect, lycopene, human tissues, particle size, in vitro drug release, confocal laser scanning microscopy, green fluorescence, human umbilical vein endothelial cells, cell viability, proinflammatory cytokine levels, cellular internalisation, SA‐based carrier delivery system, time 48.0 hour     

Fabrication of poly(D,L‐lactic acid) nanoparticles as delivery system for sustained release of L‐theanine

L‐theanine is present in tea as a unique, free, non‐protein amino acid. Due to various beneficial effects on brain activity, it is widely used as a nutraceutical. After consumption, it is rapidly absorbed and metabolised followed by excretion through urine. Therefore, the authors developed an L‐theanine delivery system by encapsulating into polymeric nanoparticles to release it slowly and make it available for a longer period of time. Poly(D, L‐lactic acid) nanoparticle (PLANP) was fabricated by the double emulsion method and L‐theanine was encapsulated into it (PLANP‐T). Spherical nanoparticles with a hydrodynamic diameter of 247 and 278 nm and surface charge of −14.5 and −25.7 mV for PLANP and PLANP‐T, respectively, were fabricated. The Fourier transform infrared spectroscopic data indicated encapsulation of L‐theanine into PLANP. The PLANP showed high L‐theanine encapsulation capacity (71.65%) with a sustained release character. The maximum release (66.3%) of L‐theanine was recorded in pH 7.3 at 48 h. The release kinetics followed the Higuchi model and the release mechanism was determined as super case‐II transport (erosion). This slow release will make it available to the target tissue for a longer period of time (sustain release effect) and will also avoid immediate metabolism and clearance from the circulation.Inspec keywords: nanomedicine, pH, polymers, nanofabrication, emulsions, biomedical materials, drug delivery systems, nanoparticles, Fourier transform infrared spectraOther keywords: brain activity, L‐theanine delivery system, polymeric nanoparticles, double emulsion method, spherical nanoparticles, surface charge, L‐theanine encapsulation capacity, poly(D, L‐lactic acid) nanoparticles, nonprotein amino acid, urine, hydrodynamic diameter, Fourier transform infrared spectroscopy, time 48.0 hour, voltage ‐25.7 mV, voltage ‐14.5 mV, size 278.0 nm, size 247.0 nm, target tissue, Higuchi model, pH     

Solvent effect in the synthesis of hydrophobic drug‐loaded polymer nanoparticles

Quercetin is an abundant flavonoid in fruits, vegetables such as onion, tea leaves, cranberry, radish leaves etc. with numerous biological activities and widely used as an effective antioxidant. Its low solubility in water and chemical decomposition in intestinal environment are predicaments in delivery through dietary or oral intake. Noble polymeric nanoparticles are of particular interest today because of their applications in many areas. Polymer nanoparticles have attracted the interest of many research groups and have been utilised in an increasing number of fields such as site targeted drug delivery in cancer research during the last decades. Various techniques can be used to produce polymer nanoparticles, such as solvent evaporation, salting‐out, dialysis, supercritical fluid technology etc. The choice of method depends on a number of factors, such as, particle size, particle size distribution, area of application, etc. In the present study, single emulsion‐solvent evaporation technique has been utilised with two different organic solvents: acetone and chloroform/methanol to prepare quercetin loaded poly(D,L‐lactide‐co‐glycolide) nanoparticles. According to the authors’ observations acetone is a better solvent for encapsulating quercetin in polymer nanoparticles owing to its physical and chemical properties.Inspec keywords: solvent effects, nanofabrication, nanomedicine, nanoparticles, hydrophobicity, cancer, drug delivery systems, emulsions, evaporationOther keywords: particle size, single emulsion‐solvent evaporation technique, acetone, chloroform/methanol, cancer research, drug delivery, antioxidant, flavonoid, quercetin, hydrophobic drug‐loaded polymer nanoparticles, nanoparticle synthesis, solvent effect     

Formulation and characterisation of poly(lactic‐co‐glycolic acid) encapsulated clove oil nanoparticles for dental applications

This study investigated synthesis and characterisation of Nano‐PLGA (poly(lactic‐co‐glycolic acid))/CO (clove‐oil) nanoparticles. The delivery of drug‐loaded nanoparticles to demineralised dentin substrates and their morphological association with a two‐step etch‐and‐rinse adhesive system was studied. The effect of Nano‐PLGA/CO pretreatment on micro‐tensile bond strength of resin‐dentin bonding was scrutinised. This study employed CO‐containing PLGA nanoparticles as a delivery vehicle for sustainable drug release inside dentinal‐tubules for potential dental applications. Emulsion evaporation resulted in uniformly distributed negatively‐charged Nano‐PLGA/Blank and Nano‐PLGA/CO nanoparticles. Scanning electron microscopy/ transmission electron microscopy revealed even spherical nanoparticles with smooth texture. High CO‐loading and encapsulation were achieved. Moreover, controlled CO‐release was evidenced after 15 days, in‐vitro and ex‐vivo. Nanoparticles exhibited low initial toxicity towards human mesenchymal stem cells with excellent antibacterial properties. Nanoparticles penetration inside dentinal‐tubules indicated a close correlation with resin‐tags. Nano‐PLGA/CO pretreatment indicated reduction in short‐term bond strength of resin‐dentin specimens. Nano‐PLGA/CO as model drug‐loaded nanoparticles showed excellent metric and antibacterial properties, low toxicity and sustained CO release. However, the loading of nanoparticles with CO up to ∼10 mg (Nano‐PLGA/CO:10) did not adversely affect short‐term bond strength values. This drug‐delivery strategy could be further expanded to deliver other pulp‐sedative agents and medications with other dental relevance.Inspec keywords: nanoparticles, dentistry, encapsulation, filled polymers, nanofabrication, nanocomposites, nanomedicine, biomedical materials, drug delivery systems, adhesives, tensile strength, biomechanics, resins, proteins, molecular biophysics, biochemistry, emulsions, evaporation, scanning electron microscopy, transmission electron microscopy, texture, cellular biophysics, antibacterial activity, bonds (chemical)Other keywords: poly(lactic‐co‐glycolic acid) encapsulated clove oil nanoparticles, dental applications, drug‐loaded nanoparticle delivery, demineralised dentin substrates, morphological association, two‐step etch‐and‐rinse adhesive system, simulated pulpal pressure, nanoPLGA‐CO pretreatment, microtensile bond strength, resin‐dentin bonded specimens, CO‐containing PLGA nanoparticles, delivery vehicle, sustainable drug release, dentinal‐tubules, potential dental applications, emulsion evaporation, uniformly‐distributed negatively‐charged nanoPLGA‐blank, scanning electron microscopy‐transmission electron microscopy, spherical nanoparticles, smooth texture, high CO‐loading, controlled CO‐release, human mesenchymal stem cells, antibacterial properties, antibiofilm properties, deep nanoparticle penetration, resin‐tags, short‐term bond strength, resin‐dentin specimens, metric properties, antibacterial properties, sustained CO release, pulp‐sedative agents, time 15 d     

Core/shell nanoassembly of amphiphilic naproxen‐polyethylene glycol: synthesis,characterisation and evaluation as drug delivery system

Small molecule‐based amphiphiles self‐assemble into nanostructures (micelles) in aqueous medium which are currently being explored as novel drug delivery systems. Here, naproxen‐polyethylene glycol (N‐PEG), a small molecule‐derived amphiphile, has been synthesised, characterised and evaluated as hydrophobic drug carrier. ¹ H, ¹³ C Nuclear magnetic resonance (NMR), mass spectrometry (MS) and Fourier‐transform infrared spectroscopy (FTIR) confirmed the formation of N‐PEG and dynamic light scattering (DLS) revealed the formation of nano‐sized structures of ∼228 nm. Transmission electron microscope (TEM) analysis showed aggregation behaviour of the structures with average size of ∼230 nm. Biodegradability aspect of the micellar‐structured N‐PEG was demonstrated by lipase‐mediated degradation studies using DLS and TEM. High encapsulation efficiency followed by release in a sustained manner of a well‐known anticancer drug, doxorubicin, demonstrated the feasibility of the new drug delivery system. These results advocate the promising potential of N‐PEG micelles as efficient drug delivery system for specific delivery to cancerous cells in vitro and in vivo.Inspec keywords: cancer, biodegradable materials, cellular biophysics, encapsulation, biomedical materials, drugs, nanofabrication, drug delivery systems, nanomedicine, self‐assembly, nanoparticles, transmission electron microscopy, colloids, molecular biophysics, light scattering, hydrophobicity, biochemistry, enzymes, core‐shell nanostructures, nanocomposites, proton magnetic resonance, Fourier transform infrared spectra, mass spectroscopic chemical analysisOther keywords: hydrophobic drug carrier, nanosized structures, transmission electron microscope analysis, doxorubicin, N‐PEG micelles, core/shell nanoassembly, amphiphilic naproxen‐polyethylene glycol, drug delivery system, small molecule‐based amphiphiles self‐assemble, small molecule‐derived amphiphile, ¹ H NMR, ¹³ C NMR, MS, FTIR, dynamic light scattering, aggregation behaviour, biodegradability aspect, lipase‐mediated degradation studies, encapsulation efficiency, cancerous cells     

Controllable synthesis and characterisation of palladium (II) anticancer complex‐loaded colloidal gelatin nanoparticles as a novel sustained‐release delivery system in cancer therapy

Over the past few years, there have been several attempts to deliver anticancer drugs into the body. It has been shown that compared to other available carriers, colloidal gelatin nanoparticles (CGNPs) have distinct properties due to their exceptional physico‐chemical and biological characteristics. In this study, a novel water‐soluble palladium (II) anticancer complex was first synthesised, and then loaded into CGNPs. The CGNPs were synthesised through a two‐step desolvation method with an average particle size of 378 nm. After confirming the stability of the drug in the nanoparticles, the drug‐loaded CGNPs were tested for in vitro cytotoxicity against human breast cancer cells. The results showed that the average drug encapsulating efficiency and drug loading of CGNPs were 64 and 10 ± 2.1% (w/w), respectively. There was a slight shift to higher values of cumulative release, when the samples were tested in lower pH values. In addition, the in vitro cytotoxicity test indicated that the number of growing cells significantly decreased after 48 h in the presence of different concentrations of drug. The results also demonstrated that the released drug could bind to DNA by a static mechanism at low concentrations (0.57 µM) on the basis of hydrophobic and hydrogen binding interactions.Inspec keywords: cancer, drug delivery systems, drugs, palladium compounds, colloids, gelatin, nanoparticles, nanomedicine, biomedical materials, nanofabrication, nanocomposites, molecular biophysics, molecular configurations, pH, solubility, particle size, cellular biophysics, encapsulation, DNA, hydrophobicity, hydrogen bondsOther keywords: controllable synthesis, sustained‐release delivery system, cancer therapy, palladium (II) anticancer complex‐loaded colloidal gelatin nanoparticles, anticancer drug delivery, physicochemical characteristics, biological characteristics, therapeutic pathways, water‐soluble palladium (II) anticancer complex, two‐step desolvation method, particle size, drug stability, gelatin matrix, drug‐loaded CGNPs, in vitro cytotoxic activity, human breast cancer cells, average drug encapsulating efficiency, pH values, cell growth, drug concentrations, DNA, static mechanism, hydrophobic interaction, hydrogen binding interactions     

Corrosion and drug release properties of EN-plating/PLGA composite coating on MAO film

The electroless nickel plating/poly(dl-lactide-co-glycolide) composite coating (EN-plating/PLGA composite coating) was fabricated on the surface of the micro-arc oxidation (MAO) film of the magnesium alloy AZ81 to double control the corrosion and drug release in the hanks' solution. The EN-plating was fabricated on the MAO coating to improve the corrosion resistance by overlaying most pores and micro-cracks on the surface of the MAO film. Meanwhile, a double layered organic poly(dl-lactide-co-glycolide)/paclitaxel (PLGA/PTX) drug releasing coating with a top layered PLGA drug controlled releasing coating on EN plating was prepared to control the drug release rate by adjusting the different lactide: glycolide (LA:GA) ratio of PLGA. Scanning electron microscopy (SEM) and the X-ray powder diffraction (XRD) were used to analyze the morphology and the composition of the EN-plating. The corrosion behavior of the magnesium alloy substrate and the status of the drug in the PLGA matrix were respectively evaluated by Potentiodynamic polarization and Differential scanning calorimetry (DSC). The drug release was determined by ultraviolet–visible (UV–visible) spectrophotometer. EN-plating coating which was composed of compact cauliflower nodules was uniform in size and defect free with no pores or cracks. EN-plating could seal the microcracks and microholes on the outer layer of the MAO coating effectively. The corrosion resistance was improved by preventing the corrosive ions from diffusing to the magnesium alloy substrate. The drug release rate of PTX exhibited a nearly linear sustained-release profile with no significant burst releases.     

Design and development of artemisinin and dexamethasone loaded topical nanodispersion for the effective treatment of age‐related macular degeneration

Age‐related macular degeneration (AMD) is a disease affecting the macula by the new blood vessels formation. AMD is widely treated with a combination of anti‐angiogenic and anti‐vascular endothelial growth factor (VEGF) agents. The topical administration of nanodispersions showed enhanced ocular residence time with controlled and prolonged drug delivery to the disease site at the back of the eye. In the present study we developed and characterized nanodispersion containing anti‐angiogenic (artemisinin) and anti‐VEGF agent (dexamethasone) for the topical ocular administration in order to obtain a required drug concentration in the posterior part of the eye. The nanodispersions were prepared with varying concentration of polymer, polyvinyl pyrrolidone K90 and polymeric surfactant, Poloxamer 407. The nanodispersions were found to be smooth and spherical in shape with a size range of 12–26 nm. In‐vitro drug release studies showed the 90–101% of artemisinin and 55–103% of dexamethasone release from the nanodispersions. The blank formulation with a high concentration of polymer and polymeric surfactant showed an acceptable level of haemolysis and DNA damage. The chorioallantoic membrane assay suggested that the nanodispersion possess good anti‐angiogenic effect. Hence the formulated artemisinin and dexamethasone nanodispersion may have the great potential for the AMD treatment.Inspec keywords: drug delivery systems, drugs, eye, blood vessels, DNA, biochemistry, nanofabrication, molecular biophysics, nanomedicine, diseases, biomedical materials, polymers, membranesOther keywords: topical administration, enhanced ocular residence time, controlled prolonged drug delivery, disease site, eye, topical ocular administration, polymeric surfactant, dexamethasone release, dexamethasone nanodispersion, AMD treatment, blood vessel formation, drug concentration, in‐vitro drug release, antiangiogenic effect, artemisinin, dexamethasone loaded topical nanodispersion, age‐related macular degeneration effective treatment, antivascular endothelial growth factor agents, antiangiogenic endothelial growth factor agents, antiVEGF agent, polyvinyl pyrrolidone K90, polymer concentration, Poloxamer 407, size 12.0 nm to 26.0 nm, chorioallantoic membrane assay, DNA damage, haemolysis     

Nano‐encapsulated Tinospora cordifolia (Willd.) using poly (D,L‐lactide) nanoparticles educe effective control in streptozotocin‐induced type 2 diabetic rats

The therapeutics for type 2 diabetes mellitus has emerged in the current century towards nanomedicine incorporated with plant active compounds. In this study, Tinospora cordifolia loaded poly (D, L‐lactide) (PLA) nanoparticles (NPs) were evaluated in vivo for their anti‐hyperglycemic potency towards streptozotocin‐induced type 2 diabetic rats. T. cordifolia loaded PLA NPs were synthesised by the double solvent evaporation method using PLA polymer. The NPs were then characterised and administrated orally for 28 successive days to streptozotocin‐induced diabetic rats. The PLA NPs had significant anti‐diabetic effects which were equal to the existing anti‐diabetic drug glibenclamide. The antidiabetic activity is due to the synergism of compounds present in stem extract of the plant which reduced the side effects and anti‐diabetic.Inspec keywords: blood, nanofabrication, drug delivery systems, biochemistry, evaporation, nanoparticles, nanomedicine, drugs, diseases, polymers, biomedical materialsOther keywords: PLA nanoparticles, antidiabetic effects, nanoencapsulated Tinospora cordifolia, streptozotocin‐induced type 2 diabetic rats, type 2 diabetes mellitus, poly(d, l‐lactide) nanoparticles, diabetic drug glibenclamide, nanomedicine, antihyperglycemic potency, double‐solvent evaporation     

One‐Step Fabrication of Triple‐Layered Polymeric Microparticles with Layer Localization of Drugs as a Novel Drug‐Delivery System

Particulate systems have tremendous potential to achieve controlled release and targeted delivery of drugs. However, conventional single‐layered particles have several inherent limitations, including initial burst release, the inability to provide zero‐order release, and a lack of time‐delayed or pulsatile release of therapeutic agents. Multilayered particles have the potential to overcome these disadvantages. Herein, it is shown how triple‐layered polymeric microparticles can be fabricated through a simple, economical, reliable, and versatile one‐step solvent evaporation technique. Particle morphologies and layer configurations are determined by scanning electron microscopy, polymer dissolution tests, and Raman mapping. Key fabrication parameters that affect the formation of triple‐layered polymeric microparticles comprising poly(DL ‐lactide‐co‐glycolide) (50:50), poly(L ‐lactide), and poly(ethylene‐co‐vinyl acetate) (40 wt% vinyl acetate) are discussed, along with their formation mechanisms. Layer thickness and the configurations of these microparticles are altered by changing the polymer mass ratios. Finally, it is shown that drugs can be localized in specific layers of the microparticles. This fabrication process can therefore be used to tailor microparticle designs, thus allowing such “designer” particulate drug‐delivery systems to function across a wide range of applications.     

Encapsulation of the reductase component of p ‐hydroxyphenylacetate hydroxylase in poly(lactide‐co ‐glycolide) nanoparticles by three different emulsification techniques

p ‐Hydroxyphenylacetate 3‐hydroxylase component 1 (C ₁) is a useful enzyme for generating reduced flavin and NAD⁺ intermediates. In this study, poly(lactide‐co‐glycolide) (PLGA) nanoparticles (NPs) were used to encapsulate the C ₁ (PLGA‐C ₁ NPs). Enzymatic activity, stability, and reusability of PLGA‐C ₁ NPs prepared using three different methods [oil in water (o/w), water in oil in water (w/o/w), and solid in oil in water (s/o/w)] were compared. The s/o/w provided the optimal conditions for encapsulation of C ₁ (PLGA‐C _1,s NPs), giving the highest enzyme activity, stability, and reusability. The s/o/w method improves enzyme activity ∼11 and 9‐fold compared to w/o/w (PLGA‐C _1,w NPs) and o/w (PLGA‐C _1,o NPs). In addition, s/o/w prepared PLGA‐C _1,s NPs could be reused 14 times with nearly 50% activity remaining, a much higher reusability compared to PLGA‐C _1,o NPs and PLGA‐C _1,w NPs. These nanovesicles were successfully utilised to generate reduced flavin mononucleotide (FMN) and supply this cofactor to a hydroxylase enzyme that has application for synthesising anti‐inflammatory compounds. Therefore, this recycling biocatalyst prepared using the s/o/w method is effective and has the potential for use in combination with other enzymes that require reduced FMN. Application of PLGA‐C _1,s NPs may be possible in additional biocatalytic processes for chemical or biochemical production.Inspec keywords: nanoparticles, enzymes, biotechnology, biochemistry, recycling, catalysts, nanofabrication, encapsulationOther keywords: reductase component, poly(lactide‐co‐glycolide) nanoparticles, emulsification techniques, p‐hydroxyphenylacetate 3‐hydroxylase component, NAD⁺ intermediates, PLGA, enzymatic activity, PLGA‐C₁ reusability, water in oil in water methods, solid in oil in water methods, oil in water methods, optimal conditions, encapsulation, enzyme stability, enzyme reusability, s/o/w method, reduced flavin mononucleotide, hydroxylase enzyme, anti‐inflammatory compounds, recycling biocatalyst, FMN, biocatalytic processes, biochemical production, chemical production     

Pectin‐decorated selenium nanoparticles as a nanocarrier of curcumin to achieve enhanced physicochemical and biological properties

In this study, the authors developed pectin‐stabilised selenium nanoparticles (pectin‐SeNPs) for curcumin (Cur) encapsulation and evaluated their physicochemical properties and biological activities. Results showed that pectin‐SeNPs and Cur‐loaded pectin‐SeNPs (pectin‐SeNPs@Cur) exhibited monodisperse and homogeneous spherical structures in aqueous solutions with mean particle sizes of ∼61 and ∼119 nm, respectively. Cur was successfully encapsulated into pectin‐SeNPs through hydrogen bonding interactions with an encapsulation efficiency of ∼60.6%, a loading content of ∼7.4%, and a pH‐dependent and controlled drug release in vitro. After encapsulation was completed, pectin‐SeNPs@Cur showed enhanced water solubility (∼500‐fold), dispersibility, and storage stability compared with those of free Cur. Moreover, pectin‐SeNPs@Cur possessed significant free radical scavenging ability and antioxidant capacity in vitro, which were stronger than those of pectin‐SeNPs. Antitumour activity assay in vitro demonstrated that pectin‐SeNPs@Cur could inhibit the growth of HepG2 cells in a concentration‐dependent manner, and the nanocarrier pectin‐SeNPs exhibited a low cytotoxic activity against HepG2 cells. Therefore, the results suggested that pectin‐SeNPs could function as effective nanovectors for the enhancement of the water solubility, stability, and in vitro bioactivities of hydrophobic Cur.Inspec keywords: hydrogen bonds, selenium, nanoparticles, solubility, drug delivery systems, toxicology, hydrophobicity, free radicals, particle size, nanofabrication, cancer, nanomedicine, drugs, biomedical materials, encapsulation, cellular biophysics, pH, organic compoundsOther keywords: pectin‐decorated selenium nanoparticles, pectin‐stabilised selenium nanoparticles, curcumin encapsulation, Cur‐loaded pectin‐SeNPs, nanocarrier pectin‐SeNPs, physicochemical properties, biological properties, homogeneous spherical structures, monodisperse spherical structures, aqueous solutions, particle size, hydrogen bonding interactions, encapsulation efficiency, loading content, pH‐dependent drug release, in vitro controlled drug release, water solubility, free radical scavenging ability, in vitro antioxidant capacity, in vitro antitumour activity assay, HepG2 cells, cytotoxic activity, in vitro bioactivity, hydrophobic curcumin, Se     

Efavirenz oral delivery via lipid nanocapsules: formulation,optimisation, and ex‐vivo gut permeation study

Present investigation aimed to prepare, optimise, and characterise lipid nanocapsules (LNCs) for improving the solubility and bioavailability of efavirenz (EFV). EFV‐loaded LNCs were prepared by the phase‐inversion temperature method and the influence of various formulation variables was assessed using Box–Behnken design. The prepared formulations were characterised for particle size, polydispersity index (PdI), zeta potential, encapsulation efficiency (EE), and release efficiency (RE). The biocompatibility of optimised formulation on Caco‐2 cells was determined using 3‐[4,5‐dimethylthiazol‐2‐yl]‐2,5‐diphenyltetrazolium bromide assay. Then, it was subjected to ex‐vivo permeation using rat intestine. EFV‐loaded LNCs were found to be spherical shape in the range of 20–100 nm with EE of 82–97%. The best results obtained from LNCs prepared by 17.5% labrafac and 10% solutol HS15 when the volume ratio of the diluting aqueous phase to the initial emulsion was 3.5. The mean particle size, zeta potential, PdI, EE, drug loading%, and RE during 144 h of optimised formulation were confirmed to 60.71 nm, −35.93 mV, 0.09, 92.60, 7.39 and 55.96%, respectively. Optimised LNCs increased the ex vivo intestinal permeation of EFV when compared with drug suspension. Thus, LNCs could be promising for improved oral delivery of EFV.Inspec keywords: biomedical materials, solubility, drugs, encapsulation, emulsions, nanoparticles, particle size, nanofabrication, suspensions, toxicology, nanomedicine, cellular biophysics, lipid bilayers, electrokinetic effects, drug delivery systems, molecular biophysicsOther keywords: ex‐vivo permeation, diluting aqueous phase, mean particle size, zeta potential, drug loading, optimised formulation, ex vivo intestinal permeation, improved oral delivery, efavirenz oral delivery, optimisation, ex‐vivo gut permeation study, solubility, bioavailability, phase‐inversion temperature method, formulation variables, Box–Behnken design, polydispersity index, encapsulation efficiency, Caco‐2 cells, lipid nanocapsules, 3‐[4,5‐dimethylthiazol‐2‐yl]‐2,5‐diphenyltetrazolium bromide assay, EFV‐loaded LNC, drug suspension, size 20.0 nm to 100.0 nm, time 144.0 hour, size 60.71 nm, voltage ‐35.93 mV     

Preparation and characterisation of atorvastatin and curcumin‐loaded chitosan nanoformulations for oral delivery in atherosclerosis

Atorvastatin known to be a potential inhibitor of HMG‐CoA reductase involved in the synthesis of cholesterol. It is touted as miracle drug due to its profound effect in decreasing the low‐density lipoproteins in blood. Unfortunately, the high dosage used poses side‐effects relatively in comparison to other statins. On the other hand, curcumin has a diverse therapeutic potential in health and disease. However, the poor aqueous solubility and low bioavailability hinders the therapeutic potential of it when administrated orally. Therefore, it was thought to minimise the frequency of atorvastatin doses to avoid the possibility of drug resistance and also to overcome the limitations of curcumin for desirable therapeutic effects by using nanocarriers in drug delivery. In this investigation, synergistic effect of atorvastatin and curcumin nanocarriers was encapsulated by chitosan polymer. The chitosan nanocarriers prepared by ionic gelation method were characterised for their particle size, zeta potential, and other parameters. The drug‐loaded nanocarriers exhibited good encapsulation efficiency (74.25%) and showed a slow and sustained release of atorvastatin and curcumin 60.36 and 61.44%, respectively, in a span of 48 h. The drug‐loaded nanocarriers found to be haemocompatible and qualified for drug delivery in atherosclerosis.Inspec keywords: nanomedicine, drug delivery systems, diseases, cardiovascular system, enzymes, nanofabricationOther keywords: atorvastatin chitosan nanoformulation, curcumin‐loaded chitosan nanoformulation, oral delivery, atherosclerosis, potential inhibitor, HMG‐CoA reductase, cholesterol synthesis, miracle drug, low‐density lipoproteins, blood, diverse therapeutic potential, poor aqueous solubility, low bioavailability, drug resistance, nanocarriers, ionic gelation method, particle size, zeta potential, encapsulation efficiency     

Biosynthesis and characterisation of nano‐silica as potential system for carrying streptomycin at nano‐scale drug delivery

A growing trend within nanomedicine has been the fabrication of self‐delivering supramolecular nanomedicines containing a high and fixed drug content ensuring eco‐friendly conditions. This study reports on green synthesis of silica nanoparticles (Si‐NPs) using Azadirachta indica leaves extract as an effective chelating agent. X‐ray diffraction analysis and Fourier transform‐infra‐red spectroscopic examination were studied. Scanning electron microscopy analysis revealed that the average size of particles formed via plant extract as reducing agent without any surfactant is in the range of 100–170 nm while addition of cetyltrimethyl ammonium bromide were more uniform with 200 nm in size. Streptomycin as model drug was successfully loaded to green synthesised Si‐NPs, sustain release of the drug from this conjugate unit were examined. Prolong release pattern of the adsorbed drug ensure that Si‐NPs have great potential in nano‐drug delivery keeping the environment preferably biocompatible, future cytotoxic studies in this connection is helpful in achieving safe mode for nano‐drug delivery.Inspec keywords: silicon compounds, nanofabrication, nanomedicine, drug delivery systems, nanoparticles, X‐ray diffraction, Fourier transform infrared spectra, scanning electron microscopyOther keywords: nanosilica, streptomycin, nanoscale drug delivery, nanomedicine, silica nanoparticles, Azadirachta indica leaves extract, X‐ray diffraction analysis, Fourier transform‐infrared spectroscopy, scanning electron microscopy, cetyltrimethyl ammonium bromide, SiO₂      

Improvement of efficacy and decrement cytotoxicity of oxaliplatin anticancer drug using bovine serum albumin nanoparticles: synthesis,characterisation and release behaviour

To sustained release of an anticancer drug, oxaliplatin (OX), a non‐toxic and biocompatible nanocarrier based on bovine serum albumin (BSA) were synthesised by desolvation method and characterised using Fourier‐transform infrared (FTIR) spectroscopy, field emission scanning electron microscopy (FESEM), atomic force microscopy (AFM) and dynamic light scattering. The results showed that the BSA nanoparticles (BSANPs) with a mean magnitude of 187.9 ± 1.2 nm have spherical morphology with a smooth surface and a uniform distribution. Furthermore, OX was loaded onto the BSANPs and the loading was confirmed by FTIR, AFM and FESEM techniques. The percentage of encapsulation efficiency and drug loading were determined by absorption spectroscopy (UV–vis). The drug release studies showed that release of OX from BSANPs exhibited slower release rate. However, the release kinetics followed the first‐order kinetic for both of them with the non‐Fickian release behaviour. The electrochemical analysis showed stability of OX loaded onto the BSANPs (OX@BSANPs) and confirmed the diffusion mechanism. Furthermore, the results of MTT assay revealed increasing of normal cell viability and cancer cell death in the OX@BSANPs compared to only OX. It was shown that the BSANPs could be safely used as a biocompatible nanocarrier for the sustained release of OX.Inspec keywords: nanoparticles, drug delivery systems, molecular biophysics, encapsulation, cancer, proteins, drugs, cellular biophysics, light scattering, nanofabrication, atomic force microscopy, biomedical materials, diffusion, toxicology, nanomedicine, field emission scanning electron microscopy, Fourier transform infrared spectra, ultraviolet spectra, visible spectra, surface morphologyOther keywords: cytotoxicity, biocompatible nanocarrier, bovine serum albumin nanoparticles, desolvation method, atomic force microscopy, dynamic light scattering, BSA nanoparticles, FESEM, UV‐visible absorption spectroscopy, drug release rate, nonFickian release behaviour, oxaliplatin anticancer drug, Fourier‐transform infrared spectroscopy, FTIR spectroscopy, spherical morphology, encapsulation efficiency, release kinetics, first‐order kinetics, electrochemical analysis, diffusion mechanism, MTT assay, cell viability, cancer cell death     

Polyelectrolyte multilayers for bio‐applications: recent advancements

The synergistic relationship between structure and the bulk properties of polyelectrolyte multilayer (PEM) films has generated tremendous interest in their application for loading and release of bioactive species. Layer‐by‐layer assembly is the simplest, cost effective process for fabrication of such PEMs films, leading to one of the most widely accepted platforms for incorporating biological molecules with nanometre precision. The bulk reservoir properties of PEM films render them a potential candidate for applications such as biosensing, drug delivery and tissue engineering. Various biomolecules such as proteins, DNA, RNA or other desired molecules can be incorporated into the PEM stack via electrostatic interactions and various other secondary interactions such as hydrophobic interactions. The location and availability of the biological molecules within the PEM stack mediates its applicability in various fields of biomedical engineering such as programmed drug delivery. The development of advanced technologies for biomedical applications using PEM films has seen rapid progress recently. This review briefly summarises the recent successes of PEM being utilised for diverse bio‐applications.Inspec keywords: polymer electrolytes, multilayers, polymer films, molecular biophysics, biomedical materials, biochemistryOther keywords: bioapplications, polyelectrolyte multilayer films, bioactive species, layer‐by‐layer assembly, biological molecules, biosensing, drug delivery, tissue engineering, biomolecules, proteins, DNA, RNA, electrostatic interactions, secondary interactions, hydrophobic interactions, biomedical engineering, programmed drug delivery, biomedical applications, PEM films     

Improved bioavailability and pharmacokinetics of tea polyphenols by encapsulation into gelatin nanoparticles

The authors prepared surface modified (with polyelectrolyte layers), tea polyphenols (TPP) encapsulated, gelatin nanoparticles (TPP‐GNP) and characterised them. The size of the spherical nanoparticles was ∼50 nm. Number of polyelectrolyte layers and incubation time influenced the encapsulation efficiency (EE); highest EE was noted in nanoparticles with six polyelectrolyte layers (TPP‐GNP‐6L) incubated for 4 h. TPP released from TPP‐GNP‐6L in simulated biological fluids indicated protection and controlled release of TPP due to encapsulation. Mathematical modelling indicated anomalous type as a predominant mode of TPP release. TPP‐GNP‐6L exhibited enhanced pharmacokinetics in rabbit model compared with free TPP. The area under the concentration‐time curve and mean residence time were significantly higher in TPP‐GNP‐6L compared with free TPP which provide an evidence of higher bioavailability of TPP due to encapsulation. The authors demonstrated that encapsulation of TPP into GNPs favoured slow and sustained release of TPP with improved pharmacokinetics and bioavailability thereby can prolong the action of TPP.Inspec keywords: gelatin, nanoparticles, encapsulation, biomedical materials, nanomedicine, particle size, polymer electrolytes, polymer films, nanofabricationOther keywords: bioavailability, pharmacokinetics, gelatin nanoparticles, surface modified tea polyphenols, polyelectrolyte layers, spherical nanoparticle size, incubation time, encapsulation efficiency, TPP‐GNP‐6L, simulated biological fluids, mathematical modelling, TPP release, rabbit model, concentration‐time curve, mean residence time, time 4 h