Mesoporous Silica Nanoparticles Coated with Carboxymethyl Chitosan for 5-Fluorouracil Ocular Delivery: Characterization, In Vitro and In Vivo Studies.

This study investigates the development of topically applied non-invasive amino-functionalized silica nanoparticles (AMSN) and O-Carboxymethyl chitosan-coated AMSN (AMSN-CMC) for ocular delivery of 5-Fluorouracil (5-FU). Particle characterization was performed by the DLS technique (Zeta-Sizer), and structural morphology was examined by SEM and TEM. The drug encapsulation and loading were determined by the indirect method using HPLC. Physicochemical characterizations were performed by NMR, TGA, FTIR, and PXRD. In vitro release was conducted through a dialysis membrane in PBS (pH 7.4) using modified Vertical Franz diffusion cells. The mucoadhesion ability of the prepared nanoparticles was tested using the particle method by evaluating the change in zeta potential. The transcorneal permeabilities of 5-FU from AMNS-FU and AMSN-CMC-FU gel formulations were estimated through excised goat cornea and compared to that of 5-FU gel formulation. Eye irritation and ocular pharmacokinetic studies from gel formulations were evaluated in rabbit eyes. The optimum formulation of AMSN-CMC-FU was found to be nanoparticles with a particle size of 249.4 nm with a polydispersity of 0.429, encapsulation efficiency of 25.8 ± 5.8%, and drug loading capacity of 5.2 ± 1.2%. NMR spectra confirmed the coating of AMSN with the CMC layer. In addition, TGA, FTIR, and PXRD confirmed the drug loading inside the AMSN-CMC. Release profiles showed 100% of the drug was released from the 5-FU gel within 4 h, while AMSN-FU gel released 20.8% of the drug and AMSN-CMC-FU gel released around 55.6% after 4 h. AMSN-CMC-FU initially exhibited a 2.45-fold increase in transcorneal flux and apparent permeation of 5-FU compared to 5-FU gel, indicating a better corneal permeation. Higher bioavailability of AMSN-FU and AMSN-CMC-FU gel formulations was found compared to 5-FU gel in the ocular pharmacokinetic study with superior pharmacokinetics parameters of AMSN-CMC-FU gel. AMSN-CMC-FU showed 1.52- and 6.14-fold higher AUC0-inf in comparison to AMSN-FU and 5-FU gel, respectively. AMSN-CMC-FU gel and AMSN-FU gel were "minimally irritating" to rabbit eyes but showed minimal eye irritation potency in comparison to the 5 FU gel. Thus, the 5-FU loaded in AMSN-CMC gel could be used as a topical formulation for the treatment of ocular cancer.

Effects of Apigenin on Pharmacokinetics of Dasatinib and Probable Interaction Mechanism.

Dasatinib (DAS), a narrow-therapeutic index drug, Bcr-Abl, and Src family kinases multitarget inhibitor have been approved for chronic myelogenous leukemia (CML) and Ph-positive acute lymphocytic leukemia (Ph+ ALL). Apigenin (APG) has a long history of human usage in food, herbs, health supplements, and traditional medicine, and it poses low risk of damage. The concomitant use of APG containing herbs/foods and traditional medicine may alter the pharmacokinetics of DAS, that probably lead to possible herb-drug interactions. The pharmacokinetic interaction of APG pretreatment with DAS in rat plasma following single and co-oral dosing was successfully deliberated using the UPLC-MS/MS method. The in vivo pharmacokinetics and protein expression of CYP3A2, Pgp-MDR1, and BCPR/ABCG2 demonstrate that APG pretreatment has potential to drastically changed the DAS pharmacokinetics where escalation in the Cmax, AUC(0-t), AUMC(0-inf_obs), T1/2, Tmax, and MRT and reduction in Kel, Vd, and Cl significantly in rats pretreated with APG 40 mg/kg, thus escalating systemic bioavailability and increasing the rate of absorption via modulation of CYP3A2, Pgp-MDR1, and BCPR/ABCG2 protein expression. Therefore, the concomitant consumption of APG containing food or traditional herb with DAS may cause serious life-threatening drug interactions and more systematic clinical study on herb-drug interactions is required, as well as adequate regulation in herbal safety and efficacy.

Development and Evaluation of Chitosan Nanoparticles for Ocular Delivery of Tedizolid Phosphate.

This study investigates the development of topically applied non-invasive chitosan-nanoparticles (CSNPs) for ocular delivery of tedizolid phosphate (TZP) for the treatment of MRSA-related ocular and orbital infections. An ionic-gelation method was used to prepare TZP-encapsulated CSNPs using tripolyphosphate-sodium (TPP) as cross-linker. Particle characterization was performed by the DLS technique (Zeta-Sizer), structural morphology was observed by SEM. The drug encapsulation and loading were determined by the indirect method. In-vitro release was conducted through dialysis bags in simulated tear fluid (pH 7) with 0.25% Tween-80. Physicochemical characterizations were performed for ocular suitability of CSNPS. An antimicrobial assay was conducted on different strains of Gram-positive bacteria. Eye-irritation from CSNPs was checked in rabbits. Transcorneal flux and apparent permeability of TZP from CSNPs was estimated through excised rabbit cornea. Ionic interaction between the anionic and cationic functional groups of TPP and CS, respectively, resulted in the formation of CSNPs at varying weight ratios of CS/TPP with magnetic stirring (700 rpm) for 4 h. The CS/TPP weight ratio of 3.11:1 with 10 mg of TZP resulted in optimal-sized CSNPs (129.13 nm) with high encapsulation (82%) and better drug loading (7%). Release profiles indicated 82% of the drug was released from the TZP aqueous suspension (TZP-AqS) within 1 h, while it took 12 h from F2 to release 78% of the drug. Sustained release of TZP from F2 was confirmed by applying different release kinetics models. Linearity in the profile (suggested by Higuchi's model) indicated the sustained release property CSNPs. F2 has shown significantly increased (p < 0.05) antibacterial activity against some Gram-positive strains including one MRSA strain (SA-6538). F2 exhibited a 2.4-fold increased transcorneal flux and apparent permeation of TZP as compared to TZP-AqS, indicating the better corneal retention. No sign or symptoms of discomfort in the rabbits' eyes were noted during the irritation test with F2 and blank CSNPs, indicating the non-irritant property of the TZP-CSNPs. Thus, the TZP-loaded CSNPs have strong potential for topical use in the treatment of ocular MRSA infections and related inflammatory conditions.

Identification of Doxorubicin as Repurposing Inhibitory Drug for MERS-CoV PLpro.

Middle East respiratory syndrome coronavirus (MERS-CoV), belonging to the betacoronavirus genus can cause severe respiratory illnesses, accompanied by pneumonia, multiorgan failure, and ultimately death. CoVs have the ability to transgress species barriers and spread swiftly into new host species, with human-to-human transmission causing epidemic diseases. Despite the severe public health threat of MERS-CoV, there are currently no vaccines or drugs available for its treatment. MERS-CoV papain-like protease (PLpro) is a key enzyme that plays an important role in its replication. In the present study, we evaluated the inhibitory activities of doxorubicin (DOX) against the recombinant MERS-CoV PLpro by employing protease inhibition assays. Hydrolysis of fluorogenic peptide from the Z-RLRGG-AMC-peptide bond in the presence of DOX showed an IC50 value of 1.67 µM at 30 min. Subsequently, we confirmed the interaction between DOX and MERS-CoV PLpro by thermal shift assay (TSA), and DOX increased ΔTm by ~20 °C, clearly indicating a coherent interaction between the MERS-CoV PL protease and DOX. The binding site of DOX on MERS-CoV PLpro was assessed using docking techniques and molecular dynamic (MD) simulations. DOX bound to the thumb region of the catalytic domain of the MERS-CoV PLpro. MD simulation results showed flexible BL2 loops, as well as other potential residues, such as R231, R233, and G276 of MERS-CoV PLpro. Development of drug repurposing is a remarkable opportunity to quickly examine the efficacy of different aspects of treating various diseases. Protease inhibitors have been found to be effective against MERS-CoV to date, and numerous candidates are currently undergoing clinical trials to prove this. Our effort follows a in similar direction.

Abemaciclib-loaded ethylcellulose based nanosponges for sustained cytotoxicity against MCF-7 and MDA-MB-231 human breast cancer cells lines.

Abemaciclib (AC) is a novel, orally available drug molecule approved for the treatment of breast cancer. Due to its low bioavailability, its administration frequency is two to three times a day that can decrease patient compliance. Sustained release formulation are needed for prolong the action and to reduce the adverse effects. The aim of current study was to develop sustained release NSs of AC. Nanosponges (NSs) was prepared by emulsion-solvent diffusion method using ethyl-cellulose (EC) and Kolliphor P-188 (KP-188) as sustained-release polymer and surfactant, respectively. Effects of varying surfactant concentration and drug: polymer proportions on the particle size (PS), polydispersity index (PDI), zeta potential (ζP), entrapment efficiency (%EE), and drug loading (%DL) were investigated. The results of AC loaded NSs (ACN1-ACN5) exhibited PS (366.3-842.2 nm), PDI (0.448-0.853), ζP (-8.21 to -19.7 mV), %EE (48.45-79.36%) and %DL (7.69-19.17%), respectively. Moreover, ACN2 showed sustained release of Abemaciclib (77.12 ± 2.54%) in 24 h Higuchi matrix as best fit kinetics model. MTT assay signified ACN2 as potentials cytotoxic nanocarrier against MCF-7 and MDA-MB-231 human breast cancer cells. Further, ACN2 displayed drug release property without variation in the % release after exposing the product at 25 °C, 5 °C, and 45 °C storage conditions for six months. This investigation proved that the developed NSs would be an efficient carrier to sustain the release of AC in order to improve efficacy against breast cancer.

Formulation and in vitro evaluation of topical nanosponge-based gel containing butenafine for the treatment of fungal skin infection.

In the current study, four formulae (BNS1-BNS4) of butenafine (BTF) loaded nanosponges (NS) were fabricated by solvent emulsification technology, using different concentration of ethyl cellulose (EC) and polyvinyl alcohol (PVA) as a rate retarding polymer and surfactant, respectively. Prepared NS were characterized for particle size (PS), polydispersity index (PDI), zeta potential (ZP), entrapment efficiency (EE) and drug loading (DL). Nanocarrier BNS3 was optimized based on the particle characterizations and drug encapsulation. It was further evaluated for physicochemical characterizations; FTIR, DSC, XRD and SEM. Selected NS BNS3 composed of BTF (100 mg), EC (200 mg) and 0.3% of PVA showed, PS (543 ± 0.67 nm), PDI (0.330 ± 0.02), ZP (-33.8 ± 0.89 mV), %EE (71.3 ± 0.34%) and %DL (22.8 ± 0.67%), respectively. Fabricated NS also revealed; polymer-drug compatibility, drug-encapsulation, non-crystalline state of the drug in the spherical NS as per the physicochemical evaluations. Optimized NS (BNS3) with equivalent amount of (1%, w/w or w/v) BTF was incorporated into the (1%, w/w or w/v) carbopol gel. BTF loaded NS based gel was then evaluated for viscosity, spreadability, flux, drug diffusion, antifungal, stability and skin irritation studies. BNS3 based topical gels exhibited a flux rate of 0.18 (mg/cm2.h), drug diffusion of 89.90 ± 0.87% in 24 h with Higuchi model following anomalous non-Fickian drug release. The BNS3 based-gel could be effective against pathogenic fungal strains.

Inter-kingdom prediction certainty evaluation of protein subcellular localization tools: microbial pathogenesis approach for deciphering host microbe interaction.

Microbial pathogenesis involves several aspects of host-pathogen interactions, including microbial proteins targeting host subcellular compartments and subsequent effects on host physiology. Such studies are supported by experimental data, but recent detection of bacterial proteins localization through computational eukaryotic subcellular protein targeting prediction tools has also come into practice. We evaluated inter-kingdom prediction certainty of these tools. The bacterial proteins experimentally known to target host subcellular compartments were predicted with eukaryotic subcellular targeting prediction tools, and prediction certainty was assessed. The results indicate that these tools alone are not sufficient for inter-kingdom protein targeting prediction. The correct prediction of pathogen's protein subcellular targeting depends on several factors, including presence of localization signal, transmembrane domain and molecular weight, etc., in addition to approach for subcellular targeting prediction. The detection of protein targeting in endomembrane system is comparatively difficult, as the proteins in this location are channelized to different compartments. In addition, the high specificity of training data set also creates low inter-kingdom prediction accuracy. Current data can help to suggest strategy for correct prediction of bacterial protein's subcellular localization in host cell.

Thermoresponsive sol-gel improves ocular bioavailability of Dipivefrin hydrochloride and potentially reduces the elevated intraocular pressure in vivo.

The present study involves the development of Dipivefrin hydrochloride (DV) containing Poloxamers (P407 and P188)-Carbopol-934 (CP) based thermoresponsive-gels for the management of elevated intraocular pressure (IOP). Optimal formulation was evaluated for gelation temperature (Tgel), physicochemical and viscoelastic properties, in-vitro gel dissolution and drug release studies. The in-vivo safety, precorneal retention, ocular pharmacokinetics and efficacy in reducing IOP were also evaluated. Tgel of DV-containing thermoresponsive-gels were between 35.1 and 38.9 °C and it was Poloxamers and CP concentrations dependent. The optimal formulation (F8), composed of 20% P407, 5% P188 and 0.15% CP (w/v), had a Tgel of 35 °C. Its viscosity indicated good flow at room temperature and ability to convert to gel at ocular temperature and the rheology studies revealed favorable characteristics for its ocular use. In precorneal retention experiment, F8 indicated significantly higher area under concentrations curves as compared to DV-aqueous suspension (DV-AqS). In-vivo ocular pharmacokinetics indicated a significant improvement in ophthalmic bioavailability of epinephrine (active form of DV). F8 was non-irritant to the eyes and showed a successful, continuous and superior ability to reduce IOP compared to DV-AqS in rabbits. In conclusion, our developed system could be an appropriate substitute to the conventional DV eye preparations in the management of elevated IOP.

Solubility measurement, Hansen solubility parameters and solution thermodynamics of gemfibrozil in different pharmaceutically used solvents.

Gemfibrozil (GEM) is cholesterol-lowering agent which is being proposed as poorly water soluble drug (PWSD). Temperature based solubility values of GEM are not yet available in literature or any pharmacopoeia/monograph. Hence, the present studies were carried out to determine the solubility of PWSD GEM (as mole fraction) in various pharmaceutically used solvents such as water (H2O), methanol (MeOH), ethanol (EtOH), isopropanol (IPA), 1-butanol (1-BuOH), 2-butanol (2-BuOH), ethylene glycol (EG), propylene glycol (PG), polyethylene glycol-400 (PEG-400), ethyl acetate (EA), dimethyl sulfoxide (DMSO) and Transcutol® (THP) at the temperatures ranging from T = 298.2 K-318.2 K under atmospheric pressure P = 0.1 MPa. Equilibrium/experimental solubilities of GEM were recorded by applying a saturation shake flask methodology and regressed using 'van't Hoff and Apelblat models'. Hansen solubility parameters for GEM and various pharmaceutically used solvents were estimated using HSPiP software. The solid states of GEM (both in pure and equilibrated states) were studied by 'Differential Scanning Calorimetry' which confirmed no transformation of GEM after equilibrium. Experimental solubilities of GEM in mole fraction were observed maximum in THP (1.81 × 10-1) followed by DMSO, PEG-400, EA, 1-BuOH, 2-BuOH, IPA, EtOH, PG, MeOH, EG and H2O (3.24 × 10-6) at T = 318.2 K and similar tendencies were also recorded at T = 298.2 K, T = 303.2 K, T = 308.2 K and T = 313.2 K. 'Apparent thermodynamic analysis' on experimental solubilities furnished 'endothermic and entropy-driven dissolution' of GEM in each pharmaceutically used solvent.

Development and validation of UPLC-PDA method for concurrent analysis of bergenin and menisdaurin in aerial parts of Flueggea virosa (Roxb. ex Willd.).

Bergenin and menisdaurin are biologically active components which are found in plant Flueggea virosa (Phyllanthaceae). Bergenin has pharmacological actions such as chemopreventive and antihepatotoxic while menisdaurin has an anti-viral activity which needs its evaluation by an analytical method (UPLC-PDA method) that can be applied to the quality control of pharmaceutical preparations. The developed UPLC-PDA method was applied for identification and quantification of standards bergenin and menisdaurin in the methanol extract of F. virosa (FVME). The analysis was carried out using Eclipse C18 (4.6 × 100 mm, 3.5 µm) UPLC column. The optimized chromatographic condition was achieved at 0.16 mL/min flow rate using gradient system with acetonitrile and water as mobile phase. Both biomarkers were measured at λmax 235 nm in PDA detector at ambient temperature. The developed method furnished sharp and intense peaks of menisdaurin and bergenin at Rt = 2.723 and 3.068 min, respectively along with r2 > 0.99 for both. The recoveries of bergenin and menisdaurin were found in the range of 99.37-101.49% and 98.20-100.08%, respectively. With other validation data, including precision, specificity, accuracy, and robustness, this method demonstrated excellent reliability and sensitivity. The separation parameters i.e. retention, separation, and resolution factors for resolved standards (bergenin and menisdaurin) were >1, which showed good separation. The quantity of bergenin and menisdaurin in the FVME sample was found as 15.16 and 3.28% w/w, respectively. The developed UPLC-PDA method could be conveniently adopted for the routine quality control analysis.

Inter-species comparative antioxidant assay and HPTLC analysis of sakuranetin in the chloroform and ethanol extracts of aerial parts of Rhus retinorrhoea and Rhus tripartita.

CONTEXT: Extensive research on Rhus (Anacardiaceae) shows their antioxidant potential, which warrants further evaluation of its other species. OBJECTIVE: To perform a comparative antioxidant assay on extracts of R. retinorrhoea and R. tripartita, including sakuranetin quantification by a validated HPTLC method. MATERIALS AND METHODS: In vitro antioxidant assay was performed on chloroform and ethanol extracts of R. retinorrhoea Steud. ex Oliv. (RRCE and RREE) and R. tripartita (Ucria) Grande (RTCE and RTEE) by DPPH radical scavenging (at 31.25, 62.5, 125, 250 and 500 µg/mL concentrations) and ß-carotene-linoleic acid bleaching methods at 500 µg/mL concentration. Densitometric HPTLC method was developed and validated using toluene: ethyl acetate: methanol (8:2:0.2; v/v/v) as mobile phase, executed on glass-backed silica gel F254 plate and scanned at 292 nm. RESULTS: Antioxidant activity of Rhus extracts tested by the two methods (DPPH/BCB) was found in order of RTEE > RREE > RTCE > RRCE with IC50 118.67/256.26, 315.75/82.35, 827.92/380.0 and 443.69/292.75, respectively. Scanning of the HPTLC plate provided an intense peak of sakuranetin at Rf = 0.59. The estimated sakuranetin content in the dry weight of the extracts was highest in RREE (27.95 µg/mg) followed by RRCE (25.22 µg/mg), RTEE (0.487 µg/mg) and RTCE (0.0 µg/mg). Presence of sakuranetin in RREE, RRCE and RTEE supported the highest antioxidant property of the two Rhus species. Nonetheless, low sakuratenin in R. tripartita indicated the presence of other bioactive constituents responsible for synergistic antioxidant activity. CONCLUSION: The developed HPTLC method therefore guarantees its application in quality control of commercialized herbal drugs and formulations containing sakuranetin.

Effect of cryoprotection on particle size stability and preservation of chitosan nanoparticles with and without hyaluronate or alginate coating.

The aim of the present study was to determine the effect of different cryoprotectants and their concentration on the physicochemical characteristics of chitosan nanoparticles (CS-NPs). The effect of coating of CS-NPs with hyaluronic acid (HA) and alginic acid (ALG) before and after lyophilization was also evaluated. The ionic gelation method was used for the preparation of NPs and six different types of cryoprotectants (sucrose, glucose, trehalose, mannitol, polyethylene glycol-2000, and polyethylene glycol-10,000) were investigated at 5%, 10%, 20%, and 50% concentration levels. Coating of CS-NPs with HA and their protection with high amount of cryoprotectants indicated better particle size stability. Samples that were lyophilized without cryoprotectants resulted in an increase in average size due to high agglomeration. All cryoprotectants with varying amount provided some sort of size stability for the NPs except for the PEG-10,000 which had no protective effect at higher concentrations. Sucrose and trehalose sugars were found to have the highest protective effect with HA coated and uncoated CS-NPs. In conclusion, using cryoprotectants along with surface coating, the CS-NPs could achieve the desired physicochemical characteristics for a prolonged duration.

Development and validation of stability-indicating high performance liquid chromatography method to analyze gatifloxacin in bulk drug and pharmaceutical preparations.

Quantitative determination of gatifloxacin in tablets, solid lipid nanoparticles (SLNs) and eye-drops using a very simple and rapid chromatographic technique was validated and developed. Formulations were analyzed using a reverse phase SUPELCO® 516 C-18-DB, 50306-U, HPLC column (250 mm × 4.6 mm, 5 µm) and a mobile phase consisting of disodium hydrogen phosphate buffer:acetonitrile (75:25, v/v) and with orthophosphoric acid pH was adjusted to 3.3 The flow rate was 1.0 mL/min and analyte concentrations were measured using a UV-detector at 293 nm. The analyses were performed at room temperature (25 ± 2 °C). Gatifloxacin was separated in all the formulations within 2.767 min. There were linear calibration curves over a concentration range of 4.0-40 µg.mL(-1) and correlation coefficients of 0.9998 with an average recovery above 99.91%. Detection of analyte from different dosage forms at the same Rt indicates the specificity and stability of the developed method.

A Simple, Sensitive, and Greener HPLC-DAD Method for the Simultaneous Analysis of Two Novel Orexin Receptor Antagonists.

The orexin receptor antagonist (ORA) is one of the new psychopharmacological agents used in the treatment of insomnia. There are currently no documented greener high-performance liquid chromatography-diode array detector (HPLC-DAD) methods for the analysis of ORA antagonists, lemborexant (LMB) and suvorexant (SUV) simultaneously. Therefore, in this study, a simple, sensitive, and greener HPLC-DAD method has been developed for the simultaneous quantitative analysis of LMB and SUV in bulk and laboratory-prepared mixture. The developed method was validated for numerous validation parameters and evaluated for greenness. The C18 Waters Spherisorb CN (4.6 × 250 mm2; 5 µm) column was used for the chromatographic separation. The mobile phase composition was ethanol: 10 mM KH2PO4 buffer in a ratio of (60:40 v/v). The DAD detection was performed at 253 nm using a Waters DAD detector. The greenness was evaluated using the analytical Eco-Scale (AES), ChlorTox, and analytical GREEnness (AGREE) techniques. The calibration curves showed excellent linearity for LMB and SUV between the concentration range of 125-5000 ng/mL and 250-10,000 ng/mL, respectively. In addition, the proposed HPLC-DAD method was accurate, precise, robust, highly sensitive, and greener. AES, ChlorTox, and AGREE scales were predicted by the HPLC-DAD method to be 91, 1.14 g, and 0.79, respectively, showing an excellent greenness profile. The greener HPLC-DAD method was successfully used to analyze both medicines quantitatively in bulk and laboratory-prepared synthetic mixtures. The findings of this study indicated that the proposed HPLC-DAD method may be consistently applied to evaluate LMB and SUV in bulk and dosage forms.

Molybdenum Disulfide Nanosheet-Based Nanocomposite for the Topical Delivery of Umbelliferone: Evaluation of Anti-inflammatory and Analgesic Potentials.

This study aimed to develop a nanocomposite formulation comprising umbelliferone (UMB) and molybdenum disulfide (MoS2) nanosheets as a carrier, termed as the UMB-MoS2 nanocomposite in gel for topical delivery. MoS2 nanosheets were successfully synthesized via a green-hydrothermal reaction of 10 mg of ammonium molybdate and 10 mg of thiourea in 80 mL of deionized water under predetermined conditions. The UMB-MoS2 nanocomposite was prepared by sonicating UMB and MoS2 nanosheets (each of 1 mg/mL) in dimethylformamide. Scanning electron microscopy revealed crumpled nanosheets with an open-ended structure and a nanocomposite as a layered structure. The X-ray diffraction pattern revealed the amorphous nature of UMB in the UMB-MoS2 nanocomposite. Fourier-transform infrared spectra of the UMB-MoS2 nanocomposite had modified bands of the functional group, which confirmed the formation of the nanocomposite. The size and polydispersity-index (435 nm and 0.415, respectively) of the nanocomposite were within the limit for an efficient topical application. Carbopol 934 (2%) was used to prepare the UMB-MoS2 nanocomposite gel (F1) and UMB-Carbopol gel (F2, for comparative evaluation). The pH, spreadability, and viscosity of F1 were found to be 5.56, 5.89 g·cm/s, and 32.5 Pa-sec, respectively, which were optimal for the topical application of gel-based formulations. In vitro release characteristics of both formulations were deemed to be suitable for topical application, where F1 exhibited a biphasic drug release profile and a superior release rate of 94.8% compared to 43.5% for F2 at 24 h. In the carrageenan-induced rat paw edema model, the animal group treated with F1 demonstrated the lowest increase in paw thickness of 26.6%, which was significantly lower as compared to the F2-treated group (52.9%) and the diclofenac sodium-treated group (32.2%). Similarly, in the tail immersion method, F1 exhibited the highest peak tail withdrawal latency of 10.9 s, significantly greater than F2 (8.9 s) and standard treatment (10 s), indicating the superior analgesic activity of F1. This pioneering work introduces a novel UMB-MoS2 nanocomposite with promising anti-inflammatory and analgesic potentials, paving the way for further research into the biomedical applications of MoS2-based nanocarriers.

In-vivo pharmacokinetic study of ibrutinib-loaded nanostructured lipid carriers in rat plasma by sensitive spectrofluorimetric method using harmonized approach of quality by design and white analytical chemistry.

Ibrutinib, an antineoplastic agent tackling chronic lymphocytic leukemia, mantle cell lymphoma, and Waldenstrom's Macroglobulinemia, falls under the category of BCS class II drugs, characterized by a puzzling combination of low solubility and high permeability. Its oral bioavailability remains a perplexing challenge, merely reaching 2.9 % due to formidable first-pass metabolism hurdles. In a bid to surmount this obstacle, researchers embarked on a journey to develop ibrutinib-loaded NLCs (Nanostructured Lipid Carriers) using a methodology steeped in complexity: a Design of Experiments (DoE)-based hot melted ultrasonication approach. Despite a plethora of methods for analyzing ibrutinib in various matrices, the absence of a spectrofluorimetric method for assessing it in rat plasma added to the enigma. Thus emerged a spectrofluorimetric method, embodying principles of white analytical chemistry and analytical quality by design, employing a Placket-Burman design for initial method exploration and a central composite design for subsequent refinement. This method underwent rigorous validation in accordance with ICH guidelines, paving the way for its application in scrutinizing the in-vivo pharmacokinetics of ibrutinib-loaded NLCs, juxtaposed against commercially available formulations. Surprisingly, the optimized NLCs exhibited a striking 1.82-fold boost in oral bioavailability, shedding light on their potential efficacy. The environmental impact of this method was scrutinized using analytical greenness tools, affirming its eco-friendly attributes. In essence, the culmination of these efforts has not only propelled advancements in drug bioavailability but also heralded the dawn of a streamlined and environmentally conscious analytical paradigm.

Molecular insights into anti-Protozoal action of natural compounds against Cryptosporidium parvum: a molecular simulation study.

The current study used the major target protein lactate dehydrogenase Cryptosporidium parvum to identify potential binders. Our approach was a comprehensive three-step screening of 2,569 natural compounds. First, we used molecular docking techniques, followed by an advanced DeepPurpose ML model for virtual screening. The final step involved meticulous re-docking and detailed interaction analysis. The known inhibitor FX11 was considered as a control that was used for comparative analysis. Our screening process led to the identification of three promising compounds: 5353794, 18475114, and 25229652. These compounds were chosen due to their exceptional ability to form hydrogen bonds and their high binding scores with the protein. Here, all three hits showed H-bonds with the functional residues (Asn122 and Thr231) of protein, while 25229652 also showed H-bond with the catalytic site residue (His177). RMSD behaviour reflected stable and consistent complex formation for all the compounds in their last 30 ns trajectories. Principal component analysis (PCA) and free energy landscape (FEL) showed a high frequency of favourable low free energy states. Using the MM/GBSA calculation, compounds 5353794 (ΔGTOTAL = -34.92 kcal/mol) and 18475114 (ΔGTOTAL = -34.66 kcal/mol) had the highest binding affinity with the protein however, 25229652 (ΔGTOTAL = -22.62 kcal/mol) had ΔGTOTAL comparable to the control FX11. These natural compounds not only show the potential for hindering C. parvum lactate dehydrogenase but also open new avenues in its drug development. Their strong binding properties and stable interactions mark them as the prime candidates for further research and experimental validation as anti-cryptosporidiosis agents.Communicated by Ramaswamy H. Sarma.

UPLC-MS/MS Based Identification and Quantification of a Novel Dual Orexin Receptor Antagonist in Plasma Samples by Validated SWGTOX Guidelines.

Lemborexant (LEM) is a novel dual orexin receptor antagonist (DORA), recently approved for the treatment of insomnia. As with other DORAs, LEM has potential of abuse and therefore placed in Schedule IV class by the United States Drug Enforcement Administration (USDEA). In this study, a sensitive and accurate UPLC-MS/MS assay was developed for the quantification of LEM in human plasma sample using losartan as an internal standard (IS). The chromatographic separation was performed by using gradient elution of mobile phase, comprising of 10 mM ammonium acetate and acetonitrile with a flow rate of 0.3 mL/min. An Acquity UPLC BEH C18 (1.7 µm, 2.1 × 50 mm) column was used for separation of LEM and IS by maintaining the oven temperature of 40 °C. The electrospray ionization in positive mode was used for sample ionization. The precursor to product ion transition of 411.12 > 175.09 (qualifier) and 411.1 > 287.14 (quantifier) was used for detection and quantification of LEM, respectively, in multiple reaction monitoring mode. Being a drug of abuse, the assay was validated according to "Scientific Working Group for Toxicology" (SWGTOX) guidelines, including limit of detection (LOD), limit of quantification (LOQ), precision and bias, calibration model, interferences, carry-over effects, matrix effects, and stability parameters. The LOD and LOQ of the assay were 0.35 and 1.0 ng/mL, respectively. The linear range was between 1-300 ng/mL with correlation coefficient of ≥0.995. The method was also cross validated in rat plasma samples with acceptable ranges of precision and accuracy before its application for pharmacokinetic study in rats.

Topical Sustained-Release Dexamethasone-Loaded Chitosan Nanoparticles: Assessment of Drug Delivery Efficiency in a Rabbit Model of Endotoxin-Induced Uveitis.

Uveitis is an ocular illness that if not treated properly can lead to a total loss of vision. In this study, we evaluated the utility of HA-coated Dexamethasone-sodium-phosphate (DEX)-chitosan nanoparticles (CSNPs) coated with hyaluronic acid (HA) as a sustained ocular delivery vehicle for the treatment of endotoxin-induced-uveitis (EIU) in rabbits. The CSNPs were characterized for particle size, zeta potential, polydispersity, surface morphology, and physicochemical properties. Drug encapsulation, in vitro drug release, and transcorneal permeation were also evaluated. Finally, eye irritation, ocular pharmacokinetics, and pharmacodynamics were in vivo. The CSNPs ranged from 310.4 nm and 379.3 nm pre-(uncoated) and post-lyophilization (with HA-coated), respectively. The zeta potentials were +32 mV (uncoated) and -5 mV (HA-uncoated), while polydispersity was 0.178-0.427. Drug encapsulation and loading in the CSNPs were 73.56% and 6.94% (uncoated) and 71.07% and 5.54% (HA-coated), respectively. The in vitro DEX release over 12 h was 77.1% from the HA-coated and 74.2% from the uncoated NPs. The physicochemical properties of the CSNPs were stable over a 3-month period when stored at 25 °C. Around a 10-fold increased transcorneal-flux and permeability of DEX was found with HA-CSNPs compared to the DEX-aqueous solution (DEX-AqS), and the eye-irritation experiment indicated its ocular safety. After the ocular application of the CSNPs, DEX was detected in the aqueous humor (AH) till 24 h. The area under the concentrations curve (AUC0-24h) for DEX from the CSNPs was 1.87-fold (uncoated) and 2.36-fold (HA-coated) higher than DEX-AqS. The half-life (t1/2) of DEX from the uncoated and HA-coated NPs was 2.49-and 3.36-fold higher, and the ocular MRT0-inf was 2.47- and 3.15-fold greater, than that of DEX-AqS, respectively. The EIU rabbit model showed increased levels of MPO, TNF-α, and IL-6 in AH. Topical DEX-loaded CSNPs reduced MPO, TNF-α, and IL-6 levels as well as inhibited NF-κB expression. Our findings demonstrate that the DEX-CSNPs platform has improved the delivery properties and, hence, the promising anti-inflammatory effects on EIU in rabbits.

Topical Application of Linezolid-Loaded Chitosan Nanoparticles for the Treatment of Eye Infections.

Linezolid (LZ) loaded chitosan-nanoparticles (CSNPs) was developed by the ionic-gelation method using Tripolyphosphate-sodium as a crosslinker for topical application for the treatment of bacterial eye infections. Particles were characterized by Zeta-Sizer (Malvern Nano-series). TEM was used for structural morphology. Encapsulation and drug loading were estimated by measuring the unencapsulated drug. In-vitro drug release in STF (pH 7) was performed through a dialysis membrane. Storage stability of LZ-CSNPs was checked at 25 °C and 40 °C for six months. The antimicrobial potency of NPs was evaluated on different Gram-positive strains. Ocular irritation and pharmacokinetic studies were completed in rabbits. Ex-vivo transcorneal permeation of the drug was determined through the rabbit cornea. Ionic interaction among the oppositely charged functional groups of CS and TPP generated the CSNPs. The weight ratio at 3:1, wt/wt (CS/TPP) with 21.7 mg of LZ produced optimal NPs (213.7 nm with 0.387 of PDI and +23.1 mV of ZP) with 71% and 11.2% encapsulation and drug loading, respectively. Around 76.7% of LZ was released from LZ-AqS within 1 h, while 79.8% of LZ was released from CSNPs at 12 h and 90% at 24 h. The sustained drug release property of CSNPS was evaluated by applying kinetic models. The linearity in the release profile suggested that the release of LZ from CSNPs followed the Higuchi-Matrix model. LZ-CSNPs have shown 1.4 to 1.6-times improved antibacterial activity against the used bacterial strains. The LZ-CSNPs were "minimally-irritating" to rabbit eyes and exhibited 4.4-times increased transcorneal permeation of LZ than from LZ-AqS. Around 3-, 1.2- and 3.1-times improved Tmax, Cmax, and AUC0-24 h, respectively were found for LZ-CSNPs during the ocular pharmacokinetic study. AqS has shown 3.1-times faster clearance of LZ. Conclusively, LZ-CSNPs could offer a better alternative for the prolonged delivery of LZ for the treatment of bacterial infections in the eyes.