Self‐aggregated nanoparticles of N‐dodecyl,N′‐glycidyl(chitosan) as pH‐responsive drug delivery systems for quercetin

In this study, pH‐responsive amphiphilic chitosan (CS) nanoparticles were used to encapsulate quercetin (QCT) for sustained release in cancer therapy. The novel CS derivatives were obtained by synthesis with 2,3‐epoxy‐1‐propanol, also known as glycidol, followed by acylation with dodecyl aldehyde. Characterization was performed by spectroscopic, viscosimetric, and size‐determination methods. Critical aggregation concentration, morphology, entrapment efficiency, drug release profile, cytotoxicity, and hemocompatibility studies were also carried out. The average size distribution of the self‐assembling nanoparticles measured by dynamic light scattering ranged from 140 to 300 nm. In vitro QCT release and Korsmeyer–Peppas model indicated that pH had a major role in drug release. Cytotoxicity assessments indicated that the nanoparticles were non‐cytotoxic. 3‐(4,5‐Dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide assay further revealed that QCT‐loaded nanoparticles could inhibit MCF‐7 cell growth. In vitro erythrocyte‐induced hemolysis indicated the good hemocompatibility of the nanoparticles. These results suggest that the synthesized copolymers might be potential carriers for hydrophobic drugs in cancer therapy. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 45678.     

Controlled release of curcumin from thiolated starch-coated iron oxide magnetic nanoparticles: An in vitro evaluation

Thiolated starch-coated iron oxide nanoparticles containing curcumin were developed to investigate their cytotoxicity on lymphocytes and cancer cell lines. These nanoparticles were prepared using different concentrations of thiolated starch to study the effect of polymer coating on various properties of nanoparticles, namely, yield percentage, particle size, drug encapsulation, etc. Zeta potential confirmed the stability of nanoparticles. The nanoparticles with 5% polymer coating showed drug encapsulation efficiency up to 78%, while loading efficiency was higher than 80%. The cytotoxicity assay revealed excellent compatibility of the system with lymphocyte cells while considerable amount of cytotoxicity on cancer cell lines.     

Amphiphilic core-shell nanoparticles with dimer fatty acid-based aliphatic polyester core and zwitterionic poly(sulfobetaine) shell for controlled delivery of curcumin

Multifunctional nanocarriers are gaining increasing research interest as polymeric platforms for targeted drug delivery in cancer therapy and diagnosis. In this work, preparation and characterization of surfactant-free polyester nanoparticles (NPs) from a bio-based poly(butylene sebacate-co-butylene dilinoleate)s, poly(butylene sebacate) (PBSE)/poly(butylene dilinoleate) (PBDL), using nanoprecipitation, is reported. The polymeric nanoparticles (sizes narrowly distributed in a range less than 100?nm) were loaded with curcumin (CURC) with an encapsulation efficiency of 98% and drug loading (DL) content of 5–10% wt_drug/wt_polymer. The CURC-loaded nanoparticles were efficiently coated with a novel poly(sulfobetaine)-type zwitterionic polymer synthesized by nitroxide-mediated polymerization and postpolymerization functionalization step. Free and CURC formulated into noncoated and poly(sulfobetaine)-type zwitterionic polymer-coated nanoparticles were further investigated for cytotoxicity and antioxidant activity in a panel of human cell lines and rat liver microsomes, respectively. Formulated into coated NPs, CURC has superior cytotoxic and antioxidant activity versus the free drug and CURC incorporated in noncoated NPs. In addition, cell viability experiments of nonloaded nanoparticles, both coated and noncoated, demonstrated that developed nanoparticles are nontoxic, making them potentially suitable candidates for systemic passive targeting in cancer therapy, namely for treatment of solid tumors exhibiting high tumor accumulation of NPs due to enhanced permeability and retention effect. Polyzwitterion-coated nanoparticles exhibited slower drug release compared with the noncoated ones (half as much after 24?h) presumably due to the presence of the polymer shell around nanoparticles associated with a wider diffusion layer around the particles.     

pH‐sensitive Podophyllotoxin carrier for cancer cells specific delivery

A pH‐sensitive drug targeting system for solid tumors was established based on N‐isopropylacrylamide (NIPAAm) and chitosan conjugates. The mass ratio of NIPAAm and chitosan was adjusted to obtain super pH‐sensitive characteristic and the structure was studied by using Fourier transform infrared spectroscope to confirm the successful synthesis of the nanoparticles. The pH‐sensitive and drug release characteristics in vitro were studied as well. Human lung cancer cells A‐549 and human fibroblast were used to test the biocompatibility of blank and Podophyllotoxin (POD) loaded nanoparticles further to certificate the reliability of targeting acidic tumor extracellular pH. Results revealed that when charge ratio between NIPAAm and CS achieve 4:1(w/w), the drug‐loaded nanoparticles, which diameters ranged from 50 to 150 nm, exhibited super pH‐sensitive responses to tumor pH. Encapsulation and loading efficiencies were 63.7% and 2.4%, respectively. The cumulative release rate of POD, which significantly enhanced at pH 6.8 while decreased rapidly either below pH 6.5 or above pH 6.9 at 37°C. At pH 6.8, POD‐loaded nanoparticles showed cytotoxicity in MTT test and fluorescence microscopic study, comparable to that of free POD at the same POD concentrations, whereas at pH 7.4 there was little cytotoxicity at the tested concentration range. Thereby, the atoxic PNIPAAm‐g‐chitosan nanoparticle has the potentiality as a novel anticancer drugs carrier. POLYM. COMPOS., 2010. © 2009 Society of Plastics Engineers     

Delivery of cisplatin by folic acid-targeted liposomal nanoparticles into liver cancer cell line

This study aimed to prepare cisplatin-loaded PEGylated liposomal nanoparticles targeted with folic acid and evaluate their efficacy on liver cancer cell line PLC/PRF/5 (Alexander hepatoma cell line). Nanoparticles were prepared by reverse phase evaporation technique and characterized by dynamic light scattering, scanning electron microscopy, transmission electron microscopy, inductively coupled plasma optical emission spectrometry, Fourier transform infrared spectroscopy, and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide techniques. Nanoscale particles with appropriate drug encapsulation efficiency (13%) were prepared. Cytotoxicity results indicated that the superior potency of targeted cisplatin-loaded nanoparticles compared to the nontargeted counterpart with 23% more cytotoxicity. Findings of this study confirmed the potency of targeted PEGylated liposomal nanoparticles.     

Doxorubicin loading and in vitro release from poly(alkylcyanoacrylate) nanoparticles produced by redox radical emulsion polymerization

The aim of this work was to explore the capacity to load an anticancer agent Doxorubicin (Dox) on new poly(alkylcyanoacrylate) (PACA) nanoparticles prepared by redox radical emulsion polymerization (RREP). These nanoparticles present several advantages compared with the previously described PACA nanoparticles obtained by anionic emulsion polymerization (AEP). Their cytotoxicity was lower and because they do not activate the complement system, they are believed to behave like stealth nanoparticles after intravenous administration. Dox was incorporated during the preparation of the nanoparticles. However, the drug molecules were degraded by cerium IV, which is a strong oxidant agent. To avoid drug degradation, Dox must be loaded by adsorption on preformed nanoparticles. Optimal loading capacity was deduced from a Scatchard's analysis of the Dox adsorption pattern. The loading performance [Loading efficiency (LE) 74%, Loading content (LC) 3.7%], the Dox release and the amount of Dox retained by the new nanoparticles 75% were similar to those of the already well described PACA nanoparticles obtained by AEP (LE 79% and LC 4.2%, drug retention capacity 75%). It can be concluded that the loading and releasing properties make the new nanoparticles an interesting carrier candidate for the in vivo delivery of Dox. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Rationally designed curcumin laden glycopolymeric nanoparticles: Implications on cellular uptake and anticancer efficacy

Overexpression of glucose transport proteins (GLUTs) plays a pivotal role in the survival of cancer cells. Hence, targeting GLUTs receptors using glucose-based polymers can fill up the lacuna of cancer treatment by confining the dissemination and accumulation of chemotherapeutic drugs on cancer cells. The present study addressed the preparation of glycohomopolymer (PMG), PEG-based di- (PEG-b-PMG) and tri-block (PMG-b-PEG-b-PMG) polymers using atom transfer radical polymerization and their potential in the development of novel nanoparticulate drug delivery system. Curcumin-loaded glycopolymer nanoparticles were fabricated by nanoprecipitation method and investigated for various physicochemical parameters such as particle size, zeta potential, polydispersity index, drug loading, morphology, and dissolution profile. Homoglycopolymer nanoparticles exhibited lower average particle size (240.16 ± 21.41 nm), higher zeta potential (−28.72 ± 4.25 mV), and entrapment efficiency (74.61 ± 5.03%) compared to their block copolymer counterparts. Optimized formulation exhibited diffusion and dissolution-controlled drug release behavior. In vitro cell line studies demonstrated significantly superior cytotoxicity, clonogenic inhibitory and cellular uptake potential in MCF-7 cells besides receptor recognizing property of optimized curcumin nanoparticulate formulation compared to free curcumin. These findings elucidate that curcumin homoglucopyranoside nanocarriers can be a promising drug delivery option for effective management of breast cancer. © 2020 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48954.     

Switchable Fluorescence of Doxorubicin for Label-Free Imaging of Bioorthogonal Drug Release

Monitoring the release and activation of prodrug formulations provides essential information about the outcome of a therapy. While the prodrug delivery can be confirmed by using different imaging techniques, confirming the release of active payload by using imaging is a challenge. Here, we have discovered that the switchable fluorescence of doxorubicin can validate drug release upon its uncaging reaction with a highly specific chemical partner. We have observed that the conjugation of doxorubicin with a trans-cyclooctene (TCO) diminishes its fluorescence at 595 nm. This quenched fluorescence of the doxorubicin prodrug is recovered upon its bond-cleaving reaction with tetrazine. Clinically assessed iron oxide nanoparticles were used to formulate a doxorubicin nanodrug. The release of doxorubicin from the nanodrug was studied under various experimental conditions. A fivefold increase in doxorubicin fluorescence is observed after complete release. The studies were carried out in vitro in MDA-MB-231 breast cancer cells. An increase in Dox signal was observed upon tetrazine administration. This switchable fluorescence mechanism of Dox could be employed for fundamental studies, that is, the reactivity of various tetrazine and TCO linker types under different experimental conditions. In addition, the system could be instrumental for translational research where the release and activation of doxorubicin prodrug payloads can be monitored by using optical imaging systems.     

pH sensitive functionalized hyperbranched polyester based nanoparticulate system for the receptor-mediated targeted cancer therapy

The aim of this study is to develop a novel folic acid conjugated, DL-lysine modified, PEGylated, the 3rd generation hyperbranched polymer (HBP-PEG-Lys-FA) for use in receptor-mediated therapy. 5-fluorouracil, model anti-cancer drug, loaded nanoparticles were found an average size of 177?nm with loading efficiency of 23.18%. In vitro drug release studies demonstrated that nanoparticles showed pH-dependent release. HBP-PEG-Lys-FA were efficiently taken up by HeLa cells and specificity of targeted nanoparticles to folate receptors of cells was proved. It was concluded that the HBP-PEG-Lys-FA nanoparticles can provide an advantage on delivering of the drug efficiently into the cytosol for cancer therapy.     

Synthesis and Characterization of Asparaginase Bound Silver Nanocomposite Against Ovarian Cancer Cell Line A2780 and Lung Cancer Cell Line A549

Development of new strategies of drug delivery is essential for effective treatment of cancer. In the present work, nanobiocomposite of fungal asparaginase was produced by immobilizing with silver nanoparticles. Asparaginase bound silver nanoparticle has shown higher enzyme activity than crude asparaginase. The primary and secondary amine/amide functional groups were found responsible for binding of asparaginase to silver nanoparticles. The silver nanobiocomposite of asparaginase was found to have smooth surface and crystalline in nature. The size of the nanobiocomposites ranged from 60 to 80 nm. The cytotoxicity of silver nanobiocomposite of asparaginase was found to be higher than free asparaginase on ovarian cancer cell line. The silver nanobiocomposite of asparaginase showed better cytotoxicity against ovarian cancer cell line A2780 than lung cancer cell line A549. Thus the synthesized silver nanobiocomposite of asparaginase can be used as an effective anticancer agent against lung cancer.     

pH响应改性木质素纳米粒子的制备及释药性能

以酶解木质素（EHL）和N-乙烯基吡咯烷酮（NVP）为主要原料，通过自由基聚合和自组装得到了直径约为50 nm的pH响应性马来酰化木质素-g-聚乙烯吡咯烷酮（MEHL-g-PVP）纳米粒子。考察了化学修饰、聚合物浓度、水滴加速度、搅拌速度、初始水含量和投药量对纳米粒子的形貌、尺寸和载药性能的影响。结果表明，纳米粒子的最大药物负载量可达到35.1%，包封率为64.3%。体外药物释放表明，MEHL-g-PVP具有明显的pH响应能力，在模拟人体内肠道环境和胃液中，布洛芬（IBU）的72h释放量分别为11.1%和63.75%。体外细胞毒性实验结果表明，MEHL-g-PVP载药纳米粒子对正常细胞无细胞毒性，而对结肠癌细胞的具有很好地抑制作用。MEHL-g-PVP纳米粒子有望成为口服药物的理想载体材料。     

Preparation,optimization, and characterization of simvastatin nanoparticles by electrospraying: An artificial neural networks study

The purpose of this study was to determine major factors impacting the size of simvastatin (SIM)‐loaded poly(d , l ‐lactic‐co‐glycolide) (PLGA) nanoparticles (NPs) that was prepared using electrospraying. Three variables including concentration of polymer and salt as well as solvent flow rate were used as input variables. Size of NPs was considered as output variable. For the first time, our findings using a systematic and experimental approach, showed the importance of salt concentration as the dominant factor determining the size with a sharp and reverse effect. Optimum formulation (i.e., flow rate 0.08 mL h^?1, polymer concentration 0.7 w/v %, and salt concentration 0.8 mM) was then evaluated for aqueous solubility, encapsulation efficiency, particle size, in vitro drug release pattern and cytotoxicity. A very appreciable encapsulation efficiency (90.3%) as well as sustained release profile, considerable enhancement in aqueous solubility (～5.8 fold) and high IC₅₀ (>600 µM of SIM‐loaded PLGA NPs) indicated PLGA as a promising nanocarrier for SIM. The optimum formulation had particle size, zeta potential value, polydispersity index (PDI) and drug loading of 166 nm, +3 mV, 0.62 and 9%, respectively. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43602.     

In Vitro Investigation of Self-Assembled Nanoparticles Based on Hyaluronic Acid-Deoxycholic Acid Conjugates for Controlled Release Doxorubicin: Effect of Degree of Substitution of Deoxycholic Acid

Self-assembled nanoparticles based on a hyaluronic acid-deoxycholic acid (HD) chemical conjugate with different degree of substitution (DS) of deoxycholic acid (DOCA) were prepared. The degree of substitution (DS) was determined by titration method. The nanoparticles were loaded with doxorubicin (DOX) as the model drug. The human cervical cancer (HeLa) cell line was utilized for in vitro studies and cell cytotoxicity of DOX incorporated in the HD nanoparticles was accessed by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. In addition, cellular uptake of fluorescently labeled nanoparticles was also investigated. An increase in the degree of deoxycholic acid substitution reduced the size of the nanoparticles and also enhanced their drug encapsulation efficiency (EE), which increased with the increase of DS. A higher degree of deoxycholic acid substitution also lead to a lower release rate and an initial burst release of doxorubicin from the nanoparticles. In summary, the degree of substitution allows the modulation of the particle size, drug encapsulation efficiency, drug release rate, and cell uptake efficiency of the nanoparticles. The herein developed hyaluronic acid-deoxycholic acid conjugates are a good candidate for drug delivery and could potentiate therapeutic formulations for doxorubicin–mediated cancer therapy.     

Lecithin‐acrylamido‐2‐methylpropane sulfonate based crosslinked phospholipid nanoparticles as drug carrier

In this study, a novel paclitaxel (PTX) loaded and a crosslinked solid phospholipid nanoparticles (SLN‐PTX) with negative surface charge was prepared by UV polymerization for drug delivery. Capping of positive charge of zwitterionic lecithin with negative charge of sodium 2‐acrylamido‐2‐methyl‐1‐propanesulfonate (AMPS‐Na) through cation exchange interaction produced a lecithin‐AMPS (L‐AMPS) complex. The amphiphilic and negative charged lipid complex was emulsified in the presence of emulsifier, paclitaxel, initiator, and methacrylated poly ε‐caprolacton‐diol (PCL‐MAC) as a spacer. The colloidal system was subjected to UV‐irradiation to obtain crosslinked nanoparticles. Completion of the UV‐polymerization was monitored with differential scanning calorimetry (DSC), which indicated the disappearance of exothermic peaks of vinyl groups. The nanoparticle system, having an average size of 200 nm, exhibited high drug encapsulation (96%) with negatively charged surface (zeta potential had an average of ?70 mV). PTX release profiles of the crosslinked and uncrosslinked SLN‐PTXs were studied and their pharmacological properties were compared. The crosslinked nanoparticles exhibited more controlled release behavior with longer release time compared to the uncrosslinked ones. In vitro cytotoxicity test was conducted on MCF‐7 human breast adenocarcinoma cell line, which indicated that the crosslinked SLN‐PTXs have a potential therapeutic effect for breast cancer treatments. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 44105.     

Biodegradable Periodic Mesoporous Organosilica (BPMO) Loaded with Daunorubicin: A Promising Nanoparticle-Based Anticancer Drug

Biodegradable periodic mesoporous organosilica (BPMO) nanoparticles have emerged as a promising type of nanocarrier for drug delivery, given the biodegradable feature is advantageous for clinical translation. In this paper, we report synthesis and characterization of daunorubicin (DNR) loaded BPMO. DNR was loaded onto rhodamine B-labeled BPMO that contain tetrasulfide bonds. Tumor spheroids and chicken egg tumor models were used to characterize the activity in biological settings. In the first experiment we examined the uptake of BPMO into tumor spheroids prepared from ovarian cancer cells. BPMO were efficiently taken up into tumor spheroids and inhibited their growth. In the chicken egg tumor model, intravenous injection of DNR-loaded BPMO led to the elimination of ovarian tumor. Lack of adverse effect on organs such as lung appears to be due to excellent tumor accumulation of BPMO. Thus, DNR-loaded BPMO represents a promising nanodrug compared with free DNR currently used in cancer therapy. OK     

A novel approach to prepare etoposide‐loaded poly(N‐vinyl caprolactam‐co‐methylmethacrylate) copolymeric nanoparticles and their controlled release studies

A series of copolymeric nanoparticles of methyl methacrylate and N‐vinylcaprolactam were synthesized from microemulsions containing sodium dodecyl sulfate. Etoposide as a model drug was loaded in nanoparticles during in situ polymerization. Stable nanolatex were produced and characterized for size and shape by dynamic light scattering (DLS) and transmission electron microscopy. Particles were found to be spherical in nature with size less than 50 nm. Structural characterization of copolymers was done by infrared and nuclear magnetic resonance spectroscopy. Differential scanning calorimetery (DSC) and X‐ray diffractometry (XRD) techniques were used to evaluate molecular level interaction of etoposide with nanoparticles. Drug encapsulation efficiency was determined by ultraviolet (UV) spectrometry and found to be 35–67%. DSC, XRD, and UV data suggested the molecular level dispersion of drug in the nanoparticles. In vitro release studies and in vitro cytotoxicity showed prolonged and controlled release of etoposide from nanoparticles along with IC₅₀ values of nanoparticles in the range of 0.01–0.1 mg/mL. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2013     

Nanoparticles of Poly(Lactide-Co-Glycolide)-d-a-Tocopheryl Polyethylene Glycol 1000 Succinate Random Copolymer for Cancer Treatment

Cancer is the leading cause of death worldwide. Nanomaterials and nanotechnologies could provide potential solutions. In this research, a novel biodegradable poly(lactide-co-glycolide)-d-a-tocopheryl polyethylene glycol 1000 succinate (PLGA-TPGS) random copolymer was synthesized from lactide, glycolide and d-a-tocopheryl polyethylene glycol 1000 succinate (TPGS) by ring-opening polymerization using stannous octoate as catalyst. The obtained random copolymers were characterized by ¹H NMR, FTIR, GPC and TGA. The docetaxel-loaded nanoparticles made of PLGA-TPGS copolymer were prepared by a modified solvent extraction/evaporation method. The nanoparticles were then characterized by various state-of-the-art techniques. The results revealed that the size of PLGA-TPGS nanoparticles was around 250 nm. The docetaxel-loaded PLGA-TPGS nanoparticles could achieve much faster drug release in comparison with PLGA nanoparticles. In vitro cellular uptakes of such nanoparticles were investigated by CLSM, demonstrating the fluorescence PLGA-TPGS nanoparticles could be internalized by human cervix carcinoma cells (HeLa). The results also indicated that PLGA-TPGS-based nanoparticles were biocompatible, and the docetaxel-loaded PLGA-TPGS nanoparticles had significant cytotoxicity against Hela cells. The cytotoxicity against HeLa cells for PLGA-TPGS nanoparticles was in time- and concentration-dependent manner. In conclusion, PLGA-TPGS random copolymer could be acted as a novel and promising biocompatible polymeric matrix material applicable to nanoparticle-based drug delivery system for cancer chemotherapy.     

Pilocarpine‐loaded poly(DL‐lactic‐co‐glycolic acid) nanoparticles as potential candidates for controlled drug delivery with enhanced ocular pharmacological response

The poor corneal residence time of pilocarpine, an alkaloid extracted from the leaves of the Jaborandi plant, limits its ocular application. The aim of this study was to develop, characterize, and evaluate the potential of pilocarpine entrapped by poly(DL ‐lactic‐co‐glycolic acid) (PLGA) nanoparticle carriers for ocular drug delivery. Pilocarpine‐loaded nanoparticles were prepared with a double‐emulsion (water in oil in water) method and characterized with transmission electron microscopy and X‐ray diffraction analysis. The nanoparticles exhibited an average size of 82.7 nm with an encapsulation efficiency of 57%. Stability studies showed the absence of agglomeration and constancy in the amount of drug entrapped; this indicated the solidity of these particles for long‐term use. The in vitro release studies conducted in simulated tear fluid showed the sustained release of pilocarpine. In vivo evaluation of the nanoparticles was done in a rabbit model with a miosis assay and compared to an equal dose of commercially available eye drops of pilocarpine (Pilocar drops). The in vivo miosis studies showed that the duration of miotic response increased by 40% for the nanoparticles and produced an almost 68% increase in total miotic response when compared to the eye drops. In conclusion, this study clearly demonstrated the potential of pilocarpine‐loaded PLGA nanoparticles for multiplying the therapeutic effect of ophthalmic drug delivery with enhanced bioavailability and pharmacological response. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

Graphene Oxide Loaded with Protocatechuic Acid and Chlorogenic Acid Dual Drug Nanodelivery System for Human Hepatocellular Carcinoma Therapeutic Application

Hepatocellular carcinoma or hepatoma is a primary malignant neoplasm that responsible for 75–90% of all liver cancer in humans. Nanotechnology introduced the dual drug nanodelivery method as one of the initiatives in nanomedicine for cancer therapy. Graphene oxide (GO) loaded with protocatechuic acid (PCA) and chlorogenic acid (CA) have shown some anticancer activities in both passive and active targeting. The physicochemical characterizations for nanocomposites were conducted. Cell cytotoxicity assay and lactate dehydrogenase were conducted to estimate cell cytotoxicity and the severity of cell damage. Next, nanocomposite intracellular drug uptake was analyzed using a transmission electron microscope. The accumulation and localization of fluorescent-labelled nanocomposite in the human hepatocellular carcinoma (HepG2) cells were analyzed using a fluorescent microscope. Subsequently, Annexin V- fluorescein isothiocyanate (FITC)/propidium iodide analysis showed that nanocomposites induced late apoptosis in HepG2 cells. Cell cycle arrest was ascertained at the G2/M phase. There was the depolarization of mitochondrial membrane potential and an upregulation of reactive oxygen species when HepG2 cells were induced by nanocomposites. In conclusion, HepG2 cells treated with a graphene oxide–polyethylene glycol (GOP)–PCA/CA–FA dual drug nanocomposite exhibited significant anticancer activities with less toxicity compared to pristine protocatechuic acid, chlorogenic acid and GOP–PCA/CA nanocomposite, may be due to the utilization of a folic acid-targeting nanodrug delivery system.     

Surfactant chain length effects on nanoparticles of biodegradable polymers for targeted drug delivery

Folic acid‐conjugated nanoparticles (NPs) of biodegradable polymer poly(lactic‐co‐glycolic acid) (PLGA), which were emulsified by long‐chain D ‐α‐tocopheryl polyethylene glycol succinate (vitamin E TPGS or simply TPGS) for targeted delivery of anticancer drugs, are prepared. The NPs were characterized for their size and size distribution, surface morphology, surface charge, drug encapsulation efficiency, and surface chemistry. The cellular uptake and the cytotoxicity of the drug‐loaded PLGA NPs were assessed in vitro with MCF7 breast cancer cells in close comparison with the corresponding Short‐chain TPGS (TPGS2k)‐coated PLGA NPs and the original drug. The long‐chain TPGS 2000 (TPGS2k)‐emulsified PLGA NPs showed great advantages over the short‐chain TPGS 1000 (TPGS1k)‐emulsified and the nude PLGA NPs. The folic acid‐conjugated TPGS2k‐emulsified PLGA NPs showed significant advantages in cellular uptake and therapeutic effects in vitro. The IC₅₀ value showed 90.4% less than that of the original drug. © 2012 American Institute of Chemical Engineers AIChE J, 2012