Emerging Advances in Nanocarriers Approaches in the Effective Therapy of Pain Related Disorders: Recent Evidence and Futuristic Needs.

Pain disorders are the primary cause of disability nowadays. These disorders, such as rheumatoid arthritis (RA) and osteoarthritis (OA), cause loss of function, joint pain and inflammation and deteriorate the quality of life. The treatment of these inflammatory diseases includes anti-inflammatory drugs administered via intra-articular, topical or oral routes, physical rehabilitation or surgery. Owing to the various side effects these drugs could offer, the novel approaches and nanomaterials have shown potential to manage inflammatory diseases, prolonged half-life of anti-inflammatory drugs, reduced systemic toxicity, provide specific targeting, and refined their bioavailability. This review discusses in brief about the pain pathophysiology and its types. The review summarizes the conventional therapies used to treat pain disorders and the need for novel strategies to overcome the adverse effects of conventional therapies. The review describes the recent advancements in nanotherapeutics for inflammatory diseases using several lipids, polymers and other materials and their excellent efficiency in improving the treatment over conventional therapies. The results of the nanotherapeutic studies inferred that the necessity to use nanocarriers is due to their controlled release, targeting drug delivery to inflamed tissues, low toxicity and biocompatibility. Therefore, it is possible to assert that nanotechnology will emerge as a great tool for advancing the treatment of pain disorders in the near future.

Organogel mediated co-delivery of nisin and 5-fluorouracil: a synergistic approach against skin cancer.

AIM: The present study aimed to develop topical combinatorial therapy of nisin and 5-fluorouracil in a single nanosized formulation against skin cancer. METHODS: Nisin and 5-fluorouracil were encapsulated in an organogel system (NF-OG) and investigated for morphology, physicochemical properties, cytotoxicity, encapsulation and release. NF-OG was evaluated against DMBA/TPA murine skin cancer in terms of tumour statistics, histoarchitecture, TUNEL and M1/M2 macrophages. RESULTS: The optimised NF-OG formulation exhibited particle size of 185.1 ± 11.24 nm, zeta potential of -7.93 ± 0.60 mV, offered substantial drug loading and temporal release. NF-OG therapy led to improved cytotoxicity of nisin and 5-FU against B16-F10 cells, significant decrease in tumour volume (84.983 mm3) in treated group as compared to untreated group (490.482 mm3) accompanied by restoration of histoarchitecture and repolarization of macrophages. CONCLUSION: The study yielded a promising delivery system exhibiting potent anticancer activity and forms the bases for further applications in clinical settings.

Oral sorafenib-loaded microemulsion for breast cancer: evidences from the in-vitro evaluations and pharmacokinetic studies.

Sorafenib tosylate (SFB) is a multikinase inhibitor that inhibits tumour growth and proliferation for the management of breast cancer but is also associated with issues like toxicity and drug resistance. Also, being a biopharmaceutical class II (BCS II) drug, its oral bioavailability is the other challenge. Henceforth, this report intended to encapsulate SFB into a biocompatible carrier with biodegradable components, i.e., phospholipid. The microemulsion of the SFB was prepared and characterized for the surface charge, morphology, micromeritics and drug release studies. The cell viability assay was performed on 4T1 cell lines and inferred that the IC50 value of sorafenib-loaded microemulsion (SFB-loaded ME) was enhanced compared to the naïve SFB at the concentrations of about 0.75 µM. More drug was available for the pharmacological response, as the protein binding was notably decreased, and the drug from the developed carriers was released in a controlled manner. Furthermore, the pharmacokinetic studies established that the developed nanocarrier was suitable for the oral administration of a drug by substantially enhancing the bioavailability of the drug to that of the free SFB. The results bring forth the preliminary evidence for the future scope of SFB as a successful therapeutic entity in its nano-form for effective and safer cancer chemotherapy via the oral route.

Fabrication of glutathione functionalized self-assembled magnetite nanochains for effective removal of crystal violet and phenol red dye from aqueous matrix.

A novel fabrication of magnetite (Fe3O4) nanochains, surface functionalized with glutathione (GSH), has been attempted through a basic wet reduction method, coalesced with oxidative etching for the removal of crystal violet (CV) and phenol red (PR) from an aqueous solution. The structural and functional characterizations of GSH@Fe3O4 MNPs were performed using SEM-EDX, DLS, XRD, and FTIR. The nanochain-structured adsorbent was found to have an average size of 24 ± 1.29 nm and a zeta potential value of - 6.44 mV. The batch experiments showed that GSH@Fe3O4 MNPs have a brilliant removal efficiency of 97% and 79% for CV and PR dyes, respectively, within a period of 60 min. The influence of different operational parameters like adsorbent dosage, pH, temperature, reaction time, and initial dye concentration on the removal behaviour of the adsorbent was studied in detail. The adsorbate-adsorbent reaction was tested over isotherm models, and the reaction fitted well for Langmuir isotherm with an excellent qmax value of 1619.5 mg/g and 1316.16 mg/g for CV and PR dye, respectively. The experimental results were also validated using different reaction kinetics, and it was found that the pseudo-first-order model fits well for PR dye adsorption (R2 = 0.91), while adsorption of CV dye was in best agreement with the pseudo-second-order kinetic model (R2 = 0.98). Thermodynamic studies revealed that the adsorption reaction was spontaneous and endothermic in nature. Furthermore, GSH@Fe3O4 MNPs can be reused effectively up to 5 cycles of dye removal. Major mechanisms involved in the adsorption reaction were expected to be electrostatic attraction, hydrogen bonding, and π-interactions. The efficiency of GSH@Fe3O4 MNPs in real water samples suggested that it has a high potential for dye removal from complex aqueous systems and could be used as an effective alternative for remediation of dyes contaminated water.

Lipid-based Nanocarriers Loaded with Taxanes for the Management of Breast Cancer: Promises and Challenges.

Breast cancer is the leading cause of deaths worldwide among women. Taxanes (most propitious class of diterpenes) have shown dynamic potentials in the treatment of early and metastatic breast cancer. However, challenges like poor bioavailability, low tissue-permeability, compromised aqueous solubility, and dose-dependent side-effects limit the clinical applications of these drugs. Henceforth, to overcome these challenges, various nanotechnology-based drug delivery systems are being explored for the delivery of taxanes in the management of breast cancer. One such promising nanocarrier category is lipid-based nanocarriers, which employ the meritorious features of a variety of lipids, both of natural and synthetic origin. It is also known that lipid uptake plays a significant role in breast cancer cells proliferation and tumor genesis. However, lipid-based nanocarriers could be a great choice to nanoencapsulate the poorly soluble and permeable taxanes for breast cancer management. These systems have an immense promise of bioavailability enhancement, spatial and temporal taxane delivery, improved efficacy, reduced dosing frequency, and even mild inhibition of the P-gp efflux mechanism. Apart from these promises, these carriers are not yet available for the benefit of the end-user. The present review will not only discuss the merits, progress, and promises of these systems but also ponder upon the various challenges faced by these carriers to reach the clinics for the benefit of the patients afflicted with breast cancer.

Selenium-Based Novel Epigenetic Regulators Offer Effective Chemotherapeutic Alternative with Wider Safety Margins in Experimental Colorectal Cancer.

Colorectal cancer (CRC) is a major cause of morbidity and mortality worldwide. Despite the critical involvement of epigenetic modifications in CRC, the studies on the chemotherapeutic efficacy of various epigenetic regulators remain limited. Considering the key roles of histone deacetylases (HDACs) in the regulation of diverse cellular processes, several HDAC inhibitors are implied as effective therapeutic strategies. In this context, suberoylanilide hydroxamic acid (SAHA), a 2nd-generation HDAC inhibitor, showed limited efficacy in solid tumors. Also, side effects associated with SAHA limit its clinical application. Based on the redox-modulatory and HDAC inhbitiory activities of essential trace element selenium (Se), the anti-carcinogenic potential of Se substituted SAHA, namely, SelSA-1 (25 mg kg-1), was screened for it enhanced anti-tumorigenic role and wider safety profiles in DMH-induced CRC in Balb/c mice. A multipronged approach such as in silico, biochemical, and pharmacokinetics (PK) has been used to screen, characterize, and evaluate these novel compounds in comparison to existing HDAC inhibitor SAHA. This is the first in vivo study indicating the chemotherapeutic potential of Se-based novel epigenetic regulators such as SelSA-1 in any in vivo experimental model of carcinogenesis. Pharmcological and toxicity data indicated better safety margins, bioavailability, tolerance, and elimination rate of SelSA-1 compared to classical HDAC inhibitor SAHA. Further, histological and morphological evidence demonstrated enhanced chemotherapeutic potential of SelSA-1 even at lower pharmacological doses than SAHA. This is the first in vivo study suggesting Se-based novel epigenetic regulators as potential chemotherapeutic alternatives with wider safety margins and enhanced anticancer activities.

Promises of Lipid-based Drug Delivery Systems in the Management of Breast Cancer.

Breast cancer is one of the leading types among the common non-cutaneous malignancies in women. All the curative methods available for its treatment are minimal due to their toxicity issues and dose-related side effects. Various evolving nanotechnology techniques displayed the opportunity to target breast cancer. One such delivery system is lipid-based drug delivery systems (LDDS). This concept is constrained only for the laboratory scale should be shifted to the industrial level targeting the nanomedicine with clinical benefits. This work tried to portray the advancements in the LDDS along with the lipid-based excipients, advantages, disadvantages and applications. It even helped in highlighting the recently developed lipid-based nanocarriers for breast cancer management.

Doxorubicin-Loaded Mixed Micelles for the Effective Management of Skin Carcinoma: In Vivo Anti-Tumor Activity and Biodistribution Studies.

Skin cancer is an alarming concern due to increased radiation and chemical exposure. Doxorubicin is a drug prescribed for various cancers by parenteral route. Apart from the pharmaceutical challenge of being a biopharmaceutical classification system (BCS) Class III drug, the side effects of doxorubicin are also a great concern. With an aim to enhance its safety and bioavailability, a phospholipid-based micellar system was developed. The developed nanometric and symmetric carriers not only offered substantial drug loading, but also offered a temporal drug release for longer durations. The pH-dependent drug release assured the spatial delivery at the target site, without loss of drug in the systemic circulation. The cancer cell toxicity studies along with the in vivo anti-tumor studies established the superior efficacy of the developed system. The blood profile studies and the biochemical estimations confirmed the safety of the developed nanocarriers. Lesser amount of drug was available for the microsomal degradation, as inferred by the biodistribution studies. The findings provide a proof of concept for the safer and effective doxorubicin delivery employing simple excipients like phospholipids for the management of skin cancer.

Assessing the pharmacokinetics and toxicology of polymeric micelle conjugated therapeutics.

Introduction: Analogous to nanocarriers such as nanoparticles, liposomes, nano lipoidal carriers, niosomes, and ethosomes, polymeric micelles have gained significance in the field of drug delivery. They have attracted scientists worldwide by their nanometric size, wide range of polymers available for building block synthesis, stability and potential to enhance the targeting and safety of drugs. Incorporation of drugs within the interior of polymeric micelles alters the drug pharmacokinetics, which generally results in increased efficiency.Areas covered: This review deals with the pharmacokinetics of various anti-neoplastic drugs loaded into micelles. The structure of polymeric micelles, polymers employed in their development and techniques involved will be discussed. This is followed by discussion on the pharmacokinetics of anti-cancer drugs loaded into polymeric micelles and the toxicity concerns associated.Expert opinion: Polymeric micelles are nanometeric carriers, with higher stability, polymeric flexibility and higher drug loading of poorly water-soluble drugs. These nanosystems help in increasing the bioavailability of drugs by encapsulating them within the hydrophobic core. The proper selection and design of the amphiphilic polymer for micelles is a crucial step as it decides the toxicity and the biocompatibility.

The Scope and Challenges of Vesicular Carrier-Mediated Delivery of Docetaxel for the Management of Cancer.

Since the discovery of liposomes, these vesicular carriers have attracted the researchers from all the vistas of the biomedical domain to explore and harness the potential benefits. Many novel drug delivery-based products have been approved by the United States Food and Drug Administration (USFDA) and other federal agencies of the globe, out of which the major share is of the liposomes and related carriers. Taking cognizance of it, the US-FDA has recently come up with 'Guidance for Industry on Liposome Drug Products'. In cancer management, chemotherapy is the most frequently employed approach which is still not devoid of untoward challenges and side effects. In chemotherapy, the taxanes, esp. Docetaxel shares a huge percentage in the prescription pattern. Also, the first marketed liposomal product was encasing one drug of this category. Henceforth, the present review will highlight the advances in the delivery of taxanes, in particular docetaxel, with an emphasis on the need, success and pharmacoeconomic aspects of such vesicular-carrier mediated docetaxel delivery.

Exploration of docetaxel palmitate and its solid lipid nanoparticles as a novel option for alleviating the rising concern of multi-drug resistance.

Docetaxel (DTX), a widely prescribed anticancer agent, is now associated with increased instances of multidrug resistance. Also, being a problematic BCS class IV drug, it poses challenges for the formulators. Henceforth, it was envisioned to synthesize an analogue of DTX with a biocompatible lipid, i.e., palmitic acid. The in-silico studies (molecular docking and simulation) inferred lesser binding of docetaxel palmitate (DTX-PL) with P-gp vis-à-vis DTX and paclitaxel, indicating it to be a poor substrate for P-gp efflux. Solid lipid nanoparticles (SLNs) of the conjugate were prepared using various lipids, viz. palmitic acid, stearic acid, cetyl palmitate and glyceryl monostearate. The characterization studies for the nanocarrier were performed for the surface charge, drug payload, micromeritics, release pattern of drug and surface morphology. From the cytotoxicity assays on resistant MCF-7 cells, it was established that the new analogue offered substantially decreased IC50 to that of DTX. Further, apoptosis assay also corroborated the results obtained in IC50 determination wherein, SA-SLNs showed the highest apoptotic index than free DTX. The conjugate not only enhanced the solubility but also offered lower plasma protein binding and improved pharmacokinetic and pharmacodynamic effect for DTX loaded SA-SLNs in apt animal models, and lower affinity to P-gp efflux. The studies provide preliminary evidence and a ray of hope for a better candidate in its nano version for safer and effective cancer chemotherapy.

Implementation of Quality by Design (QbD) approach in development of silver sulphadiazine loaded egg oil organogel: An improved dermatokinetic profile and therapeutic efficacy in burn wounds.

Silver Sulphadiazine (SSD) is an effective antibacterial agent considered as the gold standard for burn wound treatment. The present study aimed to investigate EO-based organogel (SSD-EOOG) as an effective carrier system for SSD delivery in burn wound management employing Quality by Design (QbD) paradigm. The organogel-based formulations were prepared employing QbD-oriented approach and further evaluated for in vivo efficacy and stability. The developed formulations were characterized for particle size, drug content, morphology, in vitro drug release, skin safety studies, ex vivo permeation, skin retention, textural analysis and pharmacodynamic studies in murine burn wound model. I-optimal mixture design was employed for optimization and evaluating different critical quality attributes (CQAs). The optimized formulation exhibited particle size of 256.5 nm with enhanced permeation (72.33 ± 1.73%) and retention (541.20 ± 22.16 µg/cm2) across skin barrier as compared to SSD-MKT. The pharmacodynamic results proved superior therapeutic efficacy of SSD-EOOG in topical burn wounds inflicted with MRSA bacterium. The results indicated wound contraction rate (78.23 ± 5.65%) and faster re-epithelialization in SSD-EOOG treated group. The present study concluded that egg oil based organogel promoted therapeutic efficacy of SSD for burn wound treatment.

Delivery of Docetaxel to Brain Employing Piperine-Tagged PLGA-Aspartic Acid Polymeric Micelles: Improved Cytotoxic and Pharmacokinetic Profiles.

In this study, poly-(lactic-co-glycolic) acid (PLGA) was conjugated with aspartic acid and was characterized by nuclear magnetic resonance and Fourier transform infrared spectroscopy. Docetaxel-loaded polymeric micelles were prepared, and piperine was tagged. The neuroblastoma cytotoxicity studies revealed a substantially higher cytotoxic potential of the developed system to that of plain docetaxel, which was further corroborated by cellular uptake employing confocal laser scanning microscopy. The hemocompatible system was able to enhance the pharmacokinetic profile in terms of 6.5-fold increment in bioavailability followed by a 3.5 times increase in the retention time in comparison with the plain drug. The single-point brain bioavailability of docetaxel was amplified by 3.3-folds, signifying a better uptake and distribution to brain employing these carriers. The findings are unique as the physically adsorbed piperine was released before the DTX, increasing the propensity of curbing the CYP3A4 enzyme, which plays a vital role in the degradation of docetaxel. Meanwhile, piperine might have compromised the P-gp efflux mechanism, which can be ascribed to the enhanced retention of the drug at the target site. The elevated target site concentrations and extended residence by a biocompatible nanocarrier supplemented with co-delivery of piperine inherit immense promises to deliver this BCS class IV drug more safely and effectively.

Aspartic acid tagged carbon nanotubols as a tool to deliver docetaxel to breast cancer cells: Reduced hemotoxicity with improved cytotoxicity.

The present study aimed to explore the potential of hydroxylated carbon nanotubes (CNTnols) conjugated with aspartic acid for the delivery of docetaxel (DTX) to breast cancer cells. The conjugate was well-characterized by FT-IR, NMR, XRD and FE-SEM. The nanoconjugate offered a hydrodynamic diameter of 86.31 ±â€¯1.02 nm, with a PDI of 0.113 and zeta potential of -41.6 ±â€¯0.17 mV. The designed nanosystem offered a controlled & pH dependent release vouching release of drug in the cancerous cytosol, not in blood, assuring delivery of the pay-load to the site of action. The carriers offered substantial hemocompatibility and lower plasma protein binding, ensuring more drug available at the site of action. The in-vitro cell viability studies in MDA MB-231 cells inferred approx. 2.8 times enhancement in the cytotoxicity potential of the conjugate vis-à-vis plain drug. Pharmacokinetic studies also corroborated the superiority of the designed nanoconjugate in terms of enhanced bioavailable fractions, reduced clearance and longer bioresidence to that of plain docetaxel. The present studies, successfully provide a workable nanomedicine, loaded with a BCS class-IV drug, for improved efficacy and safety in breast cancer.

Dithranol-loaded nanostructured lipid carrier-based gel ameliorate psoriasis in imiquimod-induced mice psoriatic plaque model.

OBJECTIVE: The aim of this study was to formulate nanostructured lipid carriers (NLCs) of dithranol-loaded in gel for ease of application and to evaluate its anti-psoriatic efficacy vis-a-vis conventional ointment formulation. SIGNIFICANCE: This study will provide an insight about the use of nanocarriers, esp. NLCs loaded with dithranol for the effective treatment of psoriasis. METHODS: Dithranol-loaded NLCs were prepared by hot melt homogenization method and characterized for particle size and percentage entrapment efficiency. The optimized NLCs were loaded into gel and evaluated for drug release, spreadability, rheological behavior, and staining. Anti-psoriatic efficacy of the NLC gel was evaluated in imiquimod (IMQ) induced psoriatic plaque model in comparison with prepared conventional ointment formulation (1.15% w/w dithranol). RESULTS: NLCs were prepared with particle size below 300 nm, polydispersity index (PDI) below 0.3 and percentage entrapment efficiency of ∼100%. The prepared NLC gel was then compared with the ointment for drug release, staining property, and efficacy. Topical application of dithranol-loaded NLC gel on IMQ-induced psoriatic plaque model reduced the symptoms of psoriasis assessed by both Psoriasis area severity index (PASI) scoring and enzyme-linked immunosorbent assay. There was a significant reduction in disease severity and cytokines like Interleukins-17, 22, 23 and Tumor necrosis factor-α by the developed system in comparison to the negative control. CONCLUSIONS: To conclude dithranol-loaded NLCs in gel base was efficacious in management of psoriasis at the same drug concentration and also offer less cloth staining to that of the ointment product.

Beta-carotene-Encapsulated Solid Lipid Nanoparticles (BC-SLNs) as Promising Vehicle for Cancer: an Investigative Assessment.

Beta-carotene (BC), a red-colored pigment found in plants and animals, is one of the most extensively investigated carotenoids due to its provitamin-A, antioxidant, and anticancer properties. The anticancer activity of BC through oral administration is severely affected due to its low bioavailability and oxidative degradation. The present study aimed to formulate and characterize solid lipid nanoparticles (SLNs) of BC for enhanced bioavailability and therapeutic efficacy. Beta-carotene-loaded solid lipid nanoparticles (BC-SLNs) were prepared employing different combinations of glyceryl monostearate and gelucire. The characterization studies were performed for particle size, morphology, release behavior, and stability. BC-SLNs were also studied for in vitro cytotoxicity in human breast cancer cell lines (MCF-7) and pharmacokinetic studies in Wistar rats. The cytotoxicity studies confirmed that encapsulation of BC within the lipid bilayers of nanoparticles did not affect its anticancer efficacy. An improved anticancer activity was observed in BC-SLNs as compared to the free BC. BC-SLNs enhanced the bioavailability of BC on oral administration by sustaining its release from the lipid core and prolongation of circulation time in the body. Similarly, area under the curve (AUCtotal) enhanced 1.92-times more when BC was incorporated into SLNs as compared to free BC. In conclusion, solid lipid nanoparticles could be an effective and promising strategy to improve the biopharmaceutical properties of carotenoids for anticancer effects.

N-desmethyl tamoxifen and quercetin-loaded multiwalled CNTs: A synergistic approach to overcome MDR in cancer cells.

Our aim was to develop multiwalled carbon nanotubes (MWCNTs)-based nanoconstructs for the codelivery of N-desmethyl tamoxifen (N-TAM) and a mild P-gp efflux inhibitor, i.e., quercetin (QT) to treat multiple drug resistant (MDR) cancer cells. The hypothesis banks on three-tier attack on the MDR mechanisms viz. drug derivatization, MWCNT permeation and P-gp inhibition. Tamoxifen was converted to N-TAM and was conjugated to carboxylated MWCNTs mediated by a biodegradable linker, i.e., tetraethylene glycol (TEG). QT was adsorbed on the conjugate to fetch the final product, i.e., N-TAM-TEG-MWCNT-QT. Spectroscopic analysis confirmed successful conjugation of N-TAM and physical adsorption of QT. The in-vitro release of N-TAM from the N-TAM-TEG-MWCNT conjugate was minimal to that of pure drug under physiological conditions, but markedly enhanced under the acidic pH of cancer cells. The developed nanometeric formulation was found to be haemo-compatible. Reduced IC50values and better cellular uptake in drug resistant MDA-MB-231 cells were observed, followed by enhanced drug availability in the systemic circulation of rodents vis-à-vis naïve drug. The smart nanosystem conferred the desired temporal drug delivery, enhanced drug efficacy, biocompatibility and conducive pharmacokinetics, which are the crucial desired attributes to tackle the increasing concern of MDR in cancer chemotherapy.

Lysine-Based C60-Fullerene Nanoconjugates for Monomethyl Fumarate Delivery: A Novel Nanomedicine for Brain Cancer Cells.

In the present study, water-soluble lysine-based C60-fullerene nanoconjugates (CF-LYS-TEG-MMF) were synthesized using a biodegradable linker for the better delivery of monomethyl fumarate (MMF) employing Prato reaction. CF-LYS-TEG-MMF resulted in enhanced cytotoxicity on neuroblastoma cells, meanwhile found to be substantially biocompatible to erythrocytes. The designed nanoconjugate exhibited a pH-based drug release pattern, minimizing the leaching of drug at plasma pH. However, the carrier offered maximum drug release at cancer cell pH, indicating huge promise in internalization of drug molecules at the site of target. The pharmacokinetics of MMF in rodents was significantly improved in terms of enhanced bioavailable drug fraction in the central compartment, reduced drug clearance, elevated plasma concentrations and prolonged biological residence of drug. Enhanced in vitro efficacy in SH-SY5Y neuroblastoma cells, improved erythrocyte compatibility, high drug loading, and conducive pharmacokinetic profile by CF-LYS-TEG-MMF offers a huge promise in brain drug delivery, dose reduction, and dosage-regimen alteration for the management of brain tumors employing MMF.

Aspartic acid derivatized hydroxylated fullerenes as drug delivery vehicles for docetaxel: an explorative study.

The objective of the present study was to deliver docetaxel to cancerous cells with enhanced efficacy and safety profile, using aspartic acid linked fullerenols. This aspartic acid derivatized fullerenol conjugate linked with docetaxel was characterized by UV, FT-IR and NMR spectroscopy. Studies for particle size, PDI, zeta potential and FE-SEM were also performed. The conjugate was evaluated for release kinetics, cancer cell cytotoxicity, cellular uptake using confocal laser microscopy and also for pharmacokinetic profile. Cytotoxic studies proved that there was almost 4.3 folds decrease in IC50 with significantly enhanced cellular uptake of the nanometric conjugates. It was observed that the bioavailability was enhanced by 5.8 folds when compared to that of pure DTX. The developed nanoconstructs were erythrocyte compatible and offered decreased protein binding. The findings are encouraging and offer a novel carrier with enhanced efficacy and safety of a drug, belonging to BCS class IV.

Fullerenol-Based Intracellular Delivery of Methotrexate: A Water-Soluble Nanoconjugate for Enhanced Cytotoxicity and Improved Pharmacokinetics.

Derivatization of fullerenes to polyhydroxylated fullerenes, i.e., fullerenols (FLU), dramatically decreases their toxicity and has been reported to enhance the solubility as well as cellular permeability. In this paper, we report synthesis of FLU as nanocarrier and subsequent chemical conjugation of Methotrexate (MTX) to FLU with a serum-stable and intracellularly hydrolysable ester bond between FLU and MTX. The conjugate was characterized for physiochemical attributes, micromeritics, drug-loading, and drug-release and evaluated for cancer cell-toxicity, cellular-uptake, hemocompatibility, protein binding, and pharmacokinetics. The developed hemocompatible FL-MTX offered lower protein binding vis-à-vis naïve drug and substantially higher drug loading. The conjugate offered pH-dependent release of 38.20 ± 1.19% at systemic pH and 85.67 ± 3.39% at the cancer cell pH. FLU-MTX-treated cells showed significant reduction in IC50 value vis-à-vis the cells treated with pure MTX. Analogously, the results from confocal scanning laser microscopy also confirmed the easy access of the dye-tagged FLU-MTX conjugate to the cell interiors. In pharmacokinetics, the AUC of MTX was enhanced by approx. 6.15 times and plasma half-life was enhanced by 2.45 times, after parenteral administration of single equivalent dose in rodents. FLU-MTX offered enhanced availability of drug to the biological system, meanwhile improved the cancer-cell cytotoxicity, sustained the effective plasma drug concentrations, and offered substantial compatibility to erythrocytes.