Biofabrication of nanoparticles: sources, synthesis, and biomedical applications.

Nanotechnology is an emerging applied science delivering crucial human interventions. Biogenic nanoparticles produced from natural sources have received attraction in recent times due to their positive attributes in both health and the environment. It is possible to produce nanoparticles using various microorganisms, plants, and marine sources. The bioreduction mechanism is generally employed for intra/extracellular synthesis of biogenic nanoparticles. Various biogenic sources have tremendous bioreduction potential, and capping agents impart stability. The obtained nanoparticles are typically characterized by conventional physical and chemical analysis techniques. Various process parameters, such as sources, ions, and temperature incubation periods, affect the production process. Unit operations such as filtration, purification, and drying play a role in the scale-up setup. Biogenic nanoparticles have extensive biomedical and healthcare applications. In this review, we summarized various sources, synthetic processes, and biomedical applications of metal nanoparticles produced by biogenic synthesis. We highlighted some of the patented inventions and their applications. The applications range from drug delivery to biosensing in various therapeutics and diagnostics. Although biogenic nanoparticles appear to be superior to their counterparts, the molecular mechanism degradation pathways, kinetics, and biodistribution are often missing in the published literature, and scientists should focus more on these aspects to move them from the bench side to clinics.

Design, preparation, and in vitro evaluation of gastroretentive floating matrix tablet of mitiglinide.

The present research is focused on developing floating matrix tablets of mitiglinide to prolong its gastric residence time for better absorption. Gastroretentive tablets were prepared using a direct compression technique with hydroxypropyl methylcellulose K15M (HPMC K15M) and sodium alginate as matrix-forming polymers and sodium bicarbonate as the gas-forming agent. A 32 full factorial design was adopted to optimize the flotation and release profile of the drug. The concentration of HPMC K15M and sodium alginate were taken as the independent variables, and the floating lag time, time required for 50% drug release, and time required for 90% drug release were taken as dependent variables. The compatibility between drug and excipients was assessed by Fourier transform infrared (FTIR) spectroscopy. The prepared tablets were evaluated for different parameters such as hardness, friability, drug content, floating time, in vitro dissolution, and stability. Dissolution data were analyzed using various kinetic models to ascertain the mechanism of drug release. Finally, a radiographic study was conducted to estimate the retention time of the optimized floating matrix tablets of mitiglinide inside the body. The results revealed that all the physical properties of the developed formulations were within standard limits. The formulation M3, with the maximum amount of both independent variables, was considered to be the optimized formulation based on the desirability value. In addition, the optimized M3 formulation showed stability for over 6 months, as evidenced by insignificant changes in lag time, drug release pattern, and other physical properties. Furthermore, radiographic examination indicated that the tablets remained afloat in gastric fluid for up to 12 h in the rabbit's stomach. In conclusion, the developed floating matrix tablet of mitiglinide could be regarded as a promising formulation that could release the drug in the stomach at a controlled rate and, hence, offer better management of type II diabetes.

Development and pharmacokinetic evaluation of osmotically controlled drug delivery system of Valganciclovir HCl for potential application in the treatment of CMV retinitis.

Valganciclovir HCl (VGH) is the widely used drug for the treatment of cytomegalovirus (CMV) retinitis infection with an induction dose of 900 mg per oral (p.o.) twice a day and a maintenance dose of 900 mg (p.o.). This required dose of the drug also leads to multiple side effects due to repeated administration. The research was highlighted to develop, formulate, optimize, and evaluate single-core osmotic pump (SCOP) tablet of VGH with the dose of 450 mg to reduce dosing frequency and associated side effects. The decrease in dose also minimizes the hepatic and nephrotic load. The optimized batch of the formulation was subjected to comparative in vitro and in vivo evaluation. The tablet core composition is the primary influencer of the drug delivery fraction in a zero order, whereas the membrane characteristics control the drug release rate. In vivo pharmacokinetic studies revealed that the newly developed osmotic formulation has controlled zero-order release for 24 h with a single dose of 450 mg while the marketed formulation requires twice administration within 24 h to maintain the plasma concentration in the therapeutic window. The pharmacokinetic study demonstrated that the developed formulation has the area under curve (AUC) of 58.415 µg h/ml with single dose while the marketed formulation shows the AUC of about 37.903 µg h/ml and 31.983 µg h/ml for first and second dose, respectively. The large AUC demonstrates the extended release of drug with a single dose and effective plasma concentration. Hence, the developed formulation can be a promising option for the treatment of CMV retinitis with the minimum dose and dosing frequency.

Mometasone furoate-loaded aspasomal gel for topical treatment of psoriasis: formulation, optimization, in vitro and in vivo performance.

BACKGROUND: Present investigation was aimed to develop aspasomal gel of Mometasone Furoate for the treatment of Psoriasis that are biologically active and deliver drug at controlled rate and decrease dosing frequency. METHODS: The vesicles were fabricated using film hydration method and optimized using 32 factorial Design. Prepared formulations were evaluated for percent drug loading, vesicle size, Zeta potential, polydispersity index and morphological studies. Gel was prepared using carbopol by loading optimized drug loaded asposomes and was evaluated for drug content, pH, viscosity and spreadability. The drug release study from the gel was done using dialysis membrane and goat skin. Anti- oxidant potency of the prepared aspasomal gel was determined by Ferric Reducing Assay whereas, in-vivo performance for inflammation and skin irritation was carried out using Wistar rats. RESULTS: Optimized aspasomes demonstrated desired properties for entrapment efficiency (74.72 ± 1.8), vesicle size (282.9 ± 1.7), polydispersity index (0.2), zeta potential (-20.2 mV) with spherical shape. The results recorded for drug release from the optimized aspasomal gel exhibited sustained release (24h) compared to the marketed cream (5h). Depot formation of Mometasone furoate loaded aspasomal gel in the epidermis was confirmed by ex vivo skin penetration study by using fluorescent marker. In-vivo study revealed no any irritation and inflammation to the skin promoting drug delivery system to treat psoriasis. CONCLUSION: In conclusion, Mometasone furoate loaded aspasomal gel releases the drug for longer duration of time and reduce dosing frequency, providing the new dimension for the treatment of psoriasis.

Development, evaluation and biodistribution of stealth liposomes of 5-fluorouracil for effective treatment of breast cancer.

The current research was undertaken to design stealth liposomes of 5-Fluorouracil for reducing its cardiotoxicity and prolong the half-life by developing long-circulating liposomes. The liposomes were prepared by the NH4EDTA gradient method, where EDTA is used as a cardioprotectant. Ascorbyl-6-palmitate was also used which helped for the synergistic effect of 5-Fluorouracil to counteract the cancer cells and provide promising application in the treatment of breast cancer cells. Taguchi design was used for screening of formulation and HSPC phospholipid was selected. The drug-excipient compatibility was checked through FTIR which showed all the excipients were compatible with the drug. The formulation was optimized by using 32 factorial design. The drug to lipid ratio (1:5) and Ascorbyl-6-Palmitate concentration (15 mg) were selected. The vesicle size of the prepared liposomes was found to be 70.12 ± 0.58 nm and uniform distribution was observed. The zeta potential and entrapment efficiency of the stealth liposomes were found -16.28 mV and 92 ± 0.007% respectively. In-vitro drug release study of formulation showed drug release of 63.50 ± 0.94% in 24 hrs. The formulation was sterilized by 0.22 µm Mixed cellulose esters (MCE) membrane filter and passed sterility test. Moreover, a biodistribution study was performed by Fluorescence microscopy and by HPLC method, which showed formulation was circulated for 24 hours. Finally, a cell line study indicated that prepared formulation possess greater anti-tumour activity. The cardiotoxicity study revealed that the stealth liposomes have minimum cardiotoxicity as compare to the plain drug.

Solid State Characterization and Dissolution Enhancement of Nevirapine Cocrystals.

Purpose: Novel cocrystals of nevirapine (NP) were designed and prepared with salicylamide and 3-hydroxy benzoic acid (3-HBA). Methods: The cocrystals were prepared by solvent drop grinding method by adding few drops of acetone to enhance the solubility and dissolution. The drug and cocrystals were characterized by differential scanning calorimetry (DSC) and powder x-ray diffraction (PXRD). The solubility of NP, its wet ground form, and cocrystals were investigated at different pH. Moreover, the effect of surfactant on solubility of cocrystals was also studied. Finally, intrinsic dissolution rate (IDR) and stability of cocrystals was examined. Results: The characterization of cocrystals by DSC and PXRD revealed formation of new solid forms due to changes in thermogram and PXRD pattern. The cocrystal of NP with 3-HBA showed 4.5 folds greater solubility in pH 1.2 buffer and 5.5 folds in 1% Tween 80 as compared to original drug. IDR of cocrystals was higher than the pure drug in 0.1 N hydrochloric acid (HCl). Moreover, cocrystals were found physically stable after 3 months as evident from unchanged IDR. Conclusion: Hence, the present research indicates the new stable solid forms of NP with improved dissolution rate than pure drug.

Enhanced brain targeting efficiency using 5-FU (fluorouracil) lipid-drug conjugated nanoparticles in brain cancer therapy.

The present investigation was aimed to synthesize, optimize, and characterize lipid/drug conjugate nanoparticles for delivering 5-fluorouracil (5-FU) to treat brain cancer. The Box-Behnken design was used to optimize the formulation, evaluate the particle size, entrapment efficiency, morphology, in vitro drug release study, and stability profiles. The in vitro performance was executed using cell line studies. The in vivo performance was carried out for pharmacokinetic studies, sterility test, biodistribution studies, and distribution lipid-drug conjugated (LDC) nanoparticles in the brain. Particle size, zeta potential, entrapment efficiency, and morphology of the optimized formulation demonstrated desirable results. In vitro release pattern showed initial fast release, followed by sustained release up to 48 h. Cytotoxic effects of blank stearic acid nanoparticles, LDC nanoparticles, and 5-FU solution on human glioma cell lines U373 MG cell showed more cytotoxicity by LDC-NPs compared to others. The values reported for LDC (AUC = 19.37 ± 0.09 µg/mL h and VD 2.4 ± 0.24 mL) and pure drug (AUC = 8.37 ± 0.04 µg/mL h and VD = 5.24 ± 0.29 mL) indicate higher concentrations of LDC in systemic circulation, while pure 5-FU was found to be largely available in tissue rather than blood circulation. The t1/2 for LDC represents an approximate rise by ninefold, while MRT (12.10 ± 0.44 h) denotes 12-fold rise than pure 5-FU indicating the prolonged circulation of LDC. Free 5-FU concentration in the brain was maximum (5.24 ± 0.01 µg/g) after 3 h, while for the optimized formulation of LDC it was twofold greater estimated as 11.52 ± 0.32 µg/g. In conclusion, the efficiency of 5-FU to treat the brain is increased when it is formulated with LDC nanoparticles.

Sustained release formulation of Ondansetron HCl using osmotic drug delivery approach.

Ondansetron HCl (OSH) is a 5-HT3 receptor antagonist indicated for the prevention of nausea and vomiting associated with radiotherapy (adults: 8 mg, t.i.d) and/or chemotherapy (adults: 8 mg, b.i.d to t.i.d) and prevention of postoperative nausea and/or vomiting (adults: 8 mg, b.i.d). In elderly subjects, bioavailability may be somewhat higher (65%) and lower clearance, presumably due to reduced hepatic first-pass metabolism. OSH is extensively distributed in the body; about 70-75% of the drug in plasma is protein-bound and terminal elimination half-life is about 3 h after oral administration. The study was aimed to develop Push-pull Osmotic Pump (PPOP) bi-layered tablets for Ondansetron HCl ER tablets. The granulation was carried out using non-aqeous solvents followed by compression, seal coating, semi permeable coating, laser drilling (0.6 mm), and drug film coating with loading dose. The drug release was controlled by swelleable osmotic polymers of pull layer and push layer and orifice on the surface of tablet. The formulations were optimized for its core composition, extended release coating (Semipermeable membrane) polymer as to plasticizer ratio and orifice diameter. Optimized formulations were evaluated for micromeritic properties and in vitro drug release. The analytical methods were developed and validated to estimate in vitro drug potency, drug release, and in vivo pharmacokinetic parameters. Stability studies were done as per the ICH guidelines. The results of in vivo study concludes that the once OSH ER dose consistently maintains plasma concentration of drug within the therapeutic window over a period of 24 h.

Enhancement of solubility and bioavailability of ambrisentan by solid dispersion using Daucus carota as a drug carrier: formulation, characterization, in vitro, and in vivo study.

Ambrisentan is an US FDA approved drug, it is the second oral endothelin A receptor antagonist known for the treatment of pulmonary arterial hypertension, but its oral administration is limited due to its poor water solubility. Hence, the objective of the investigation was focused on enhancement of solubility and bioavailability of ambrisentan by solid dispersion technique using natural Daucus carota extract as drug carrier. Drug carrier was evaluated for solubility, swelling index, viscosity, angle of repose, hydration capacity, and acute toxicity test (LD50). Ambrisentan was studied for the saturation solubility, phase solubility, and Gibbs free energy change. Compatibility of drug and the natural carrier was confirmed by DSC, FTIR, and XRD. Solid dispersions were evaluated for drug content, solubility, morphology, in vitro, and in vivo study. Screening of the natural carrier showed the desirable properties like water solubility, less swelling index, less viscosity, and acute toxicity study revealed no any clinical symptoms of toxicity. Drug and carrier interaction study confirmed the compatibility to consider its use in the formulation. Formed particles were found to be spherical with smooth surface. In vitro studies revealed higher drug release from the solid dispersion than that of the physical mixture. Bioavailability study confirms the increased absorption and bioavailability by oral administration of solid dispersion. Hence, it can be concluded that the natural Daucus carota extract can be the better alternative source for the preparation of solid dispersion and/or other dosage forms for improving solubility and bioavailability.

Formulation, physicochemical characterization and in vitro evaluation of human insulin-loaded microspheres as potential oral carrier.

The objective of the present investigation was to formulate and characterize the human insulin entrapped Eudragit S100 microspheres containing protease inhibitors and to develop an optimized formulation with desirable features. A w/o/w multiple emulsion solvent evaporation technique was employed to produce microspheres of human insulin using Eudragit S-100 as coating material and polyvinyl alcohol as a stabilizer. The resultant microspheres were evaluated for drug-excipient compatibility, encapsulation efficiency, particle size, surface morphology, micromeritic properties, enteric nature, and in vitro drug release studies. Micromeritic properties indicated good flow properties and compressibility. In present investigation formulation F6 with drug/polymer ratio (1:100) was found to be optimal in terms of evaluated parameters where it showed a significantly higher percentage of encapsulation efficiency (76.84%) with minimal drug release (3.25%) in an acidic environment. The optimized formulation (F6) also possessed good spherical shape and particle size (57.42 µm) required to achieve the desired in vitro drug release profile at pH 7.4. The results confirmed that human insulin-loaded Eudragit S-100 microspheres containing protease inhibitor possessed good encapsulation efficiency, pH dependant controlled release carrying encapsulated insulin to its optimum site of absorption. This ultimately resulted in enhanced insulin absorption and biological response.

Formulation Optimization of Human Insulin Loaded Microspheres for Controlled Oral Delivery Using Response Surface Methodology.

OBJECTIVES: The objectives of the present investigation were to prepare recombinant human insulin entrapped Eudragit-S100 microspheres containing protease inhibitors and to precisely analyze the outcome of different formulation variables on the microspheres properties using a response surface methodology to develop an optimized formulation with desirable features. METHODS: A central composite design was employed to produce microspheres of therapeutic protein by w/o/w multiple emulsion solvent evaporation technique using Eudragit S-100 as coating material and polyvinyl alcohol as a stabilizer. The effect of formulation variables (independent variables) that is levels of Eudragit S-100 (X1), therapeutic protein (X2), volumes of inner aqueous phase (X3) and external aqueous phase (X4) on dependant variables, that are encapsulation efficiency (Y1), drug release at pH 1.2 after 2 h (Y2) and drug release at pH 7.4 after of 2 h (Y3) were evaluated. RESULTS: The significant terms in the mathematical models were generated for each response parameter using multiple linear regression analysis and analysis of variance. All the formulation variables except the volume of external aqueous phase (X4) exerted a significant effect (P <0.05) on drug encapsulation efficiency (Y1) whereas first two variables, namely the levels of Eudragit S-100 (X1) and therapeutic protein (X2) materialized as the determining factors which significantly influenced drug release at pH 1.2 after 2 h (Y2) and drug release at pH 7.4 after of 2 h (Y3). The formulation was numerically optimized by framing the constraints on the dependent and independent variables using the desirability approach. The experimental values for Y1 and Y2 of optimized formulation were found to be 77.65% and 3.64%, respectively which were quite closer to results suggested by software. CONCLUSION: The results recorded indicate that the recombinant human insulin loaded Eudragit S-100 microspheres containing aprotinin have the benefits of higher loading efficiency, pH responsive and prolonged release characteristics, which may help to carry insulin to the optimum site of absorption.

Thermoreversible nanoethosomal gel for the intranasal delivery of Eletriptan hydrobromide.

The objective of the current study was to formulate and characterize thermoreversible gel of Eletriptan Hydrobromide for brain targeting via the intranasal route. Ethosomes were prepared by 3(2) factorial design with two independent variables (concentration of soya lecithin and ethanol) and two response variables [percent entrapment efficiency and vesicle size (nm)] using ethanol injection method. Formulated ethosomes were evaluated for preliminary microscopic examination followed by percent drug entrapment efficiency, vesicle size analysis, zeta potential, polydispersibility index and Transmission electron microscopy (TEM). TEM confirms spherical morphology of ethosomes, whereas Malvern zeta sizer confirms that the vesicle size was in the range of 191 ± 6.55-381.3 ± 61.0 nm. Ethosomes were incorporated in gel using poloxamer 407 and carbopol 934 as thermoreversible and mucoadhesive polymers, respectively. Ethosomal gels were evaluated for their pH, viscosity, mucoadhesive strength, in vitro drug release and ex vivo drug permeation through the sheep nasal mucosa. Mucoadhesive strength and pH was found to be 4400 ± 45 to 5500 ± 78.10 dynes/cm(2) and 6.0 ± 0.3 to 6.2 ± 0.1, respectively. In-vitro drug release from the optimized ethosomal gel formulation (G4) was found to be almost 100 % and ex vivo permeation of 4980 µg/ml with a permeability coefficient of 11.94 ± 0.04 × 10(-5) cm/s after 24 h. Histopathological study of the nasal mucosa confirmed non-toxic nature of ethosomal gels. Formulated EH loaded ethosomal thermoreversible gel could serve as the better alternative for the brain targeting via the intranasal route which in turn could subsequently improve its bioavailability.

Poloxamer 407-based intranasal thermoreversible gel of zolmitriptan-loaded nanoethosomes: formulation, optimization, evaluation and permeation studies.

Zolmitriptan is the drug of choice for migraine, but low oral bioavailability (<50%) and recurrence of migraine lead to frequent dosing and increase in associated side effects. Increase in the residence time of drug at the site of drug absorption along with direct nose to brain targeting of zolmitriptan can be a solution to the existing problems. Hence, in the present investigation, thermoreversible intranasal gel of zolmitriptan-loaded nanoethosomes was formulated by using mucoadhesive polymers to increase the residence of the drug into the nasal cavity. The preparation of ethosomes was optimized by using 3(2) factorial design for percent drug entrapment efficiency, vesicle size, zeta potential, and polydispersity index. Optimized formulation E6 showed the vesicle size (171.67 nm) and entrapment efficiency (66%) when compared with the other formulations. Thermoreversible gels prepared by using poloxamer 407 showed the phase transition temperature at 32-33 °C which was in line with the nasal physiological temperature. The optimized ethosomes were loaded into the thermoreversible mucoadhesive gel optimized by varying concentrations of poloxamer 407, carbopol 934, HPMC K100, and evaluated for gel strength, gelation temperature, mucoadhesive strength, in vitro drug release, and ex vivo drug permeation, where G3 and G6 were found to be optimized formulations. In vitro drug release was studied by different kinetic models suggested that G3 (n = 0.582) and G6 (n = 0.648) showed Korsemeyer-Peppas (KKP) model indicating non-Fickian release profiles. A permeation coefficient of 5.92 and 5.9 µg/cm(2) for G3 and G6, respectively, revealed very little difference in release rate after 24 h between both the formulations. Non-toxic nature of the gels on columnar epithelial cells was confirmed by histopathological evaluation.