Narrow Polydispersity Index Research Articles

Liquid crystal and emulsifying properties of carboxymethyl glucoside as water-soluble surfactant

ABSTRACT Three derivatives of glucosides derived from n-dodecyl alcohol in a highly pure β-anomer were synthesised with the aim to yield the liquid crystalline phase at ambient temperature with improved water solubility. Effect of variation in headgroup polarity on thermal properties, liquid crystalline phases, and structures of these derivatives of n-dodecyl β-D-glucoside (β-GlcC12) has been examined through differential scanning calorimetry, optical polarising microscopy, and small- and wide-angle X-ray scattering, respectively. Derivative bearing two carboxymethyl and two hydroxyl groups at the sugar ring i.e. n-dodecyl 2,3-bis-O-[carboxymethyl]-β-D-glucopyranoside (2,3-diCOOH-β-GlcC12) exhibited lamellar phase at the room temperature in anhydrous condition by significantly reduced the melting and clearing temperatures compared to parent compound β-GlcC12. Under excess water condition, 2,3-diCOOH-β-GlcC12 was completely soluble to form a normal micellar solution. We further investigated its foaming performance and emulsifying ability in n-octane, n-dodecane, and n-hexadecane as the oil phase. Both aqueous solution of 2,3-diCOOH-β-GlcC12 emulsified with n-dodecane and n-hexadecane formed oil-in-water emulsion layer of more than 95% of the total system volume with n-dodecane/water system consistently maintains smaller particle sizes and a narrower polydispersity index. This supports the stronger emulsifying ability and better colloidal stability of the 2,3-diCOOH-β-GlcC12 in the n-dodecane/water system than in the n-hexadecane/water system.

Synergistic effect of curcumin and Piperine loaded Niosomal nanoparticles on acute pulmonary toxicity induced by Paraquat in mice.

Paraquat (PQ), a widely used non-selective herbicide, induces severe lung toxicity by promoting cell death and tissue necrosis through the generation of reactive oxygen species (ROS) and free radicals. This study aimed to develop and evaluate novel niosomal nanoparticles (NPs) encapsulating curcumin and piperine to mitigate PQ-induced acute pulmonary toxicity in Balb/c mice. The NPs were prepared using non-ionic surfactants and cholesterol via the thin film hydration method. Characterization revealed high encapsulation efficiency (>85%), proper particle sizes (264-286nm), narrow polydispersity index (PDI) (0.19±0.04 to 0.23±0.02), and good stability over 90days. Thermal analysis confirmed successful encapsulation of curcumin and piperine within the niosomal NPs. In vivo studies showed that PQ exposure significantly elevated ROS, lipid peroxidation (LPO), and protein carbonylation (PC) levels, while reducing glutathione (GSH) levels and impairing mitochondrial function (P<0.001). However, co-treatment with curcumin- and piperine-loaded niosomal NPs effectively reversed these effects (P<0.001), improving mitochondrial function. The combined formulation of curcumin and piperine in niosomal NPs offers a promising therapeutic strategy for treating PQ-induced pulmonary toxicity, likely due to enhanced bioavailability and potent antioxidant activity.

Controlled Ring‐Opening Polymerization of Methyl Glycolide with Bifunctional Organocatalyst

AbstractA bifunctional thiourea‐amine‐based organocatalyst (Takemoto's catalyst), employing a metal‐free approach, is presented for the regioselective ring‐opening polymerization (ROP) of optically active (D and L) methyl glycolide (MG). In this study, a chiral version of Takemoto's catalyst efficiently promotes the ROP of MG at room temperature, yielding poly(lactic‐co‐glycolic acids) (PLGAs) with predicted molecular weights and narrow polydispersity indices (PDI≤1.2). These PLGAs exhibit highly alternating structures without transesterification, as confirmed by 1H NMR, SEC, and MALDI‐TOF analyses. Additionally, various macromolecular architectures, including linear and star‐shaped PLGAs, were successfully synthesized using the corresponding multi‐functional alcohol initiators while maintaining the same alternating structures and regioselectivity with PLGA obtained from benzyl alcohol as initiator. Computational studies were conducted to elucidate the mechanism of alternating PLGA formation, revealing two key transition states (TSs): TS‐1, which implicates the nucleophilic attack of the hydroxyl group of the initiator or propagating chain on the carbonyl carbon of MG, and TS‐2, which involves the subsequent ring‐opening of the cyclic ester. The results indicate that ring‐opening occurs at both the glycolyl and lactyl sites, with a preference for the glycolyl site, as supported by experimental results. The resulting atactic PLGAs are amorphous, rendering them suitable for drug delivery applications.

Self-assembled nanoparticles of PEG and poly(2-oxazoline) based lactide block copolymers

Access to self-assembled nanoparticles has become increasingly vital for the development of next generation adjuvants for the delivery of nucleic acid therapeutics. However, the block ratio of amphiphilic block copolymers plays a significant role in achieving the desired architectures and in some cases coformulation of two different block copolymers is needed. Herein, we introduce an elegant approach to self-assembled stomatocytes and cubosomes through coformulation of PEG and poly(2-oxazoline) (POx) based lactide diblock copolymers. A series of well-defined POx macroinitiators and their block copolymers with D,L-lactide (PDLLA) has been synthesized and achieved narrow polydispersity indices at high monomer conversions. Thermal analysis of block copolymers indicated tunable glass transition temperatures (Tg) ranging from 33 °C to 56 °C. Other critical factors influencing the structure of the nanoparticle included the ratio of POx-PDLLA and PEG-PDLLA blocks as well as the hydrophobicity of the POx block. Moreover, DLS and cryo-TEM analysis revealed the formation of diverse nanostructures, namely stomatocytes, pseudo-vesicles, and possibly cubosomes. This versatile platform allows for precise control over nanoparticle shapes by adjusting block lengths and coformulation ratios. This highlights the potential of using coformulations in biomedical applications, enabling the rational design of advanced nanomaterials with tailored functionalities for specific targets.

Hyaluronic acid-solid lipid nano transporter serum preparation for enhancing topical tretinoin delivery: skin safety study and visual assessment of skin.

The use of nanosized particles is becoming more popular for the topical treatment of skin conditions. In this research work, we created and investigated the effects of solid lipid nanoparticles (SLN) containing hyaluronic acid and tretinoin. Solvent emulsification diffusion method was used to prepare the SLN formulation and characterized for their physicochemical properties. Fourier transform infrared spectroscopy was used to confirm that hyaluronic acid and tretinoin were incorporated in the SLN. Furthermore, X-ray diffractogram, thermal analysis including DSC and TGA and in vitro dissolution, permeation tests were also performed along with microbial assessment. Clinical studies in human were performed to evaluate the effect of the SLN on skin wrinkles. The SLN was 750 ± 31.29nm in size, with a zeta potential of 13.07 ± 0.75mV and a narrow polydispersity index of 0.24 ± 0.12. The entrapment efficiency of tretinoin was found to be 90.07 4.79%. Clinical studies in healthy human volunteers demonstrated that 90% of the tested individuals had improved skin conditions (reduction in wrinkles), by at least one grade after 4weeks of treatment. Regarding the development on SLN, it was found that the internal phase concentration did not considerably affect the physicochemical and microbiological properties. Therefore, Hyaluronic acid has potential for the development of SLN applicable to cosmetic formulations, especially for skin. These findings show that the developed SLN have potential for use as cosmetics in the future.

Controlled Ring-Opening Polymerization of Methyl Glycolide with Bifunctional Organocatalyst.

A bifunctional thiourea-amine-based organocatalyst (Takemoto's catalyst), employing a metal-free approach, is presented for the regioselective ring-opening polymerization (ROP) of optically active (D and L) methyl glycolide (MG). In this study, a chiral version of Takemoto's catalyst efficiently promotes the ROP of MG at room temperature, yielding poly(lactic-co-glycolic acids) (PLGAs) with predicted molecular weights and narrow polydispersity indices (PDI≤1.2). These PLGAs exhibit highly alternating structures without transesterification, as confirmed by 1H NMR, SEC, and MALDI-TOF analyses. Additionally, various macromolecular architectures, including linear and star-shaped PLGAs, were successfully synthesized using corresponding multi-functional alcohol initiators while maintaining the same alternating structures and regioselectivity with PLGA obtained from benzyl alcohol as initiator. Computational studies were conducted to elucidate the mechanism of alternating PLGA formation, revealing two key transition states (TSs): TS-1, which implicates the nucleophilic attack of the hydroxyl group of the initiator or propagating chain on the carbonyl carbon of MG, and TS-2, which involves the subsequent ring-opening of the cyclic ester. The results indicate that ring-opening occurs at both the glycolyl and lactyl sites, with a preference for the glycolyl site, as supported by experimental results. The resulting atactic PLGAs are amorphous, rendering them suitable for drug delivery applications.

Ketoconazole Nanocrystals Fortified Gel for Improved Transdermal Applications

Ketoconazole (KTZ) is a commonly prescribed antifungal drug used to treat several tropical and systemic fungus infections. The topical bioavailability of KTZ is limited due to extremely low water solubility and high molecular weight. The present investigation aimed to develop a ketoconazole nanocrystals formulation to improve the biomimetic attributes. The ketoconazole nanocrystals were prepared using a top-down media milling technique with a size of less than 800 nm and a narrow polydispersity index (PDI) of 0.434. The simplex lattice design was used to further investigate the effect of change in the proportion of different stabilizers on critical product attributes such as particle size and PDI. The result of the in vitro drug release and anti-fungal study proved the superiority of the optimized KTZ nanocrystal in inhibiting fungal infection and suspension of pure drug. The optimized nanocrystals entrapped within Carbopol-934P gel had higher permeability through cellulose membrane compared, to the marketed product (2 % ketoconazole % w/w Ketodoc Cream®) with sustained release for 24 h. Moreover, the release profile indicated diffusion-controlled release from gel following Korsmeyer-Peppas. The present investigation successfully demonstrated the application of simplex lattice design and desirability function in optimizing ketoconazole nanocrystals to improve its transdermal application.

Flash precipitation of random copolymers in a micro-mixer for controlling the size and surface charge of nanoparticles.

Precisely controlling the size and surface chemistry of polymeric nanoparticles (P-NPs) is critical for their versatile engineering and biomedical applications. In this work, various NPs of amphipathic random copolymers were comparatively produced by the flash nanoprecipitation (FNP) method using a tube-in-tube type of micro-mixer up to 330 mg min-1 in production scale in a kinetically controlled manner. The NPs obtained from poly(styrene-co-maleic acid), poly(styrene-co-allyl alcohol), and poly(methyl methacrylate-co-methacrylic acid) were concurrently controlled in the range 51-819 nm in size with narrow polydispersity index (<0.1) and -44 to -16 mV in zeta potential, by depending not only on the polymeric chemistry and the concentration but also the mixing behavior of good solvents (THF, alcohols) and anti-solvent (water) under three flow regimes (laminar, vortex and turbulence, turbulent jet). Moreover, the P(St-MA) derived NPs under turbulent jet flow conditions were post-treated in the initial solution mixture for up to 16 h, resulting in lowering of the zeta potential to -52 mV from the initial -27 mV and decreasing size to 46 nm from 50 nm by further migration of hydrophilic segments with -COOH groups on the outer surface, and the removal of THF trapped in the hydrophobic core.

Starch nanoparticles with predictable size prepared by alternate treatments of ball milling and ultrasonication

In this study, starch nanoparticles (SNPs) were prepared by alternate treatments of liquid nitrogen ball milling and ultrasonication. The impact, shear and friction forces produced by ball milling, and acoustic cavitation and shear effects generated by ultrasonication disrupted starch granules to prepare SNPs. The SNPs possessed narrow particle size distribution (46.91–210.52 nm) and low polydispersity index (0.28–0.45). Additionally, the SNPs exhibited the irregular fragments with good uniformity. The relative crystallinity decreased from 34.91 % (waxy corn starch, WCS) to 0–25.91 % (SNPs), and the absorbance ratios of R1047/1022 decreased from 0.81 (WCS) to 0.60–0.76 (SNPs). The SNPs had lower thermal stability than that of WCS, characterized by a decrease in Td (temperature at maximum weight loss) from 309.39 °C (WCS) to 300.39–305.75 °C (SNPs). Furthermore, the SNPs exhibited excellent swelling power (3.48–28.02 %) and solubility (0.34–0.97 g/g). Notably, oil absorption capacity of the SNPs (9.77–15.67 g/g) was rather greater than that of WCS (1.33 g/g). Furthermore, the SNPs possessed the lower storage modulus (G′), loss modulus (G″) and viscosity than that of WCS. The SNPs with predictable size and high dispersion capability prepared in this study lay a foundation for expanding the application of SNPs.

Process Optimization of Scaled-Up Production and Biosafety Evaluation of the Dimethyl-Dioctadecyl-Ammonium Bromide/Poly(lactic acid) Nano-Vaccine.

Nano-adjuvant vaccines could induce immune responses and enhance immunogenicity. However, the application and manufacturing of nano-adjuvant is hampered by its challenging scale-up, poor reproducibility, and low security. Therefore, the present study aimed to optimize the preparation nanoparticles (NPs) using FDA-approved biopolymer materials poly(lactic acid) (PLA) and cationic lipid didodecyl-dimethyl-ammonium bromide (DDAB), develop the scale-up process, and evaluate the stability and biosafety of it. The optimum preparation conditions of DDAB/PLA NPs on a small scale were as follows: DDAB amount of 30 mg, aqueous phase volume of 90 mL, stirring rate at 550 rpm, and solidifying time of 12 h. Under the optimum conditions, the size of the NPs was about 170 nm. In scale-up preparation experiments, the vacuum rotary evaporation of 6 h and the Tangential flow ultrafiltration (TFU) method were the optimum conditions. The results suggested that DDAB/PLA NPs exhibited a uniform particle size distribution, with an average size of 150.3 ± 10.4 nm and a narrow polydispersity index (PDI) of 0.090 ± 0.13, coupled with a high antigen loading capacity of 85.4 ± 4.0%. In addition, the DDAB/PLA NPs can be stored stably for 30 days and do not have side effects caused by residual solvents. For biosafety, the acute toxicity experiments showed good tolerance of the vaccine formulation even at a high adjuvant dose. The local irritation experiment demonstrated the reversibility of muscular irritation, and the repeated toxicity experiment revealed no significant necrosis or severe lesions in mice injected with the high-dose vaccine formulation. Overall, the DDAB/PLA NPs exhibit potential for clinical translation as a safe candidate vaccine adjuvant.

Self-emulsifying drug delivery systems containing sulfate-based surfactants: Are they responsive to alkaline phosphatase?

This study aimed to develop self-emulsifying drug delivery systems (SEDDS) containing sulfate-based surfactants, namely, sodium dodecyl sulfate (SDS), sodium octyl sulfate (SOS) and sodium cetearyl sulfate (SCS), and to evaluate intestinal alkaline phosphatase (IAP)-triggered sulfate release from these SEDDS.Results showed a time-dependent release of para-nitrophenol from para-nitrophenyl phosphate (p-NPP) and para-nitrophenyl sulfate (p-NPS) when incubated with isolated IAP indicating that the enzyme can also cleave sulfate groups. Moreover, sulfate release from p-NPS and sulfate-based surfactants was observed. SEDDS containing sulfate-based surfactants exhibited a narrow droplet size distribution and polydispersity index (PDI). A droplet size of 35.31 ± 0.41 nm to 41.15 ± 0.98 nm, PDI of 0.17 ± 0.02 to 0.26 ± 0.02 and zeta potential of 9.59 ± 0.85 mV to −18.53 ± 2.75 mV were recorded. Droplet size and PDI showed a minor increase upon contact with isolated IAP. Incubation with isolated IAP caused a rapid sulfate release from sulfate-based surfactant-containing SEDDS (SDS-SEDDS, SOS-SEDDS and SCS-SEDDS). Furthermore, resulting SEDDS exhibited a non-toxic profile. According to these results, SEDDS containing sulfate-based surfactants can be considered as valid alternative to IAP-responsive drug delivery systems containing phosphorylated auxiliary agents.

Controlled Magnetite Grafted Poly(glycidyl methacrylates) for Heavy Metal Absorption and Recovery via SET-LRP

A versatile magnetite based stringent polymer for effective metal capture was prepared by reacting iron oxide based initiator with glycidyl methacrylate monomer via single-electron transfer living radical polymerization (SET-LRP) technique. The versatile grafted polymer was successfully synthesized by metal catalyzed living radical polymerization using the catalyst system Cu/N,N,N',N'',N'''-pentamethyldiethylenetriamine as the ligand. The structural confirmation of the initiator and the grafted polymer was analyzed by using instrumentation methods such as proton nuclear magnetic resonance spectroscopy, UV-visible, TGA, SEM and gel permeation chromatography for molecular weight measurements. As the polymerization time increased, both the conversion and the molecular weight were observed to increase linearly with time. Narrow dispersed lower polydispersity index (PDI) and dispensable magnetite-g-PGMA was utilized for the extract of toxic lead from the wastewater. Sustained binding was observed due to the presence of epoxide ring in the repeating units of the polymer and recovered by magnetic effect. The material shows good stability as evident by TGA curves and better affinity to toxic lead as observed by UV-visible and SEM techniques.

Exploring the Wound Healing Potential of a Cuscuta chinensis Extract-Loaded Nanoemulsion-Based Gel.

Cuscuta chinensis (C. chinensis) presents many pharmacological activities, including antidiabetic effects, and antioxidant, anti-inflammatory, and antitumor properties. However, the wound care properties of this plant have not yet been reported. Therefore, this research aimed to evaluate the antioxidant, anti-inflammatory, and antibacterial activities of ethanol and ethyl acetate C. chinensis extracts. The phytochemical markers in the extracts were analyzed using high-performance liquid chromatography (HPLC). Then, the selected C. chinensis extract was developed into a nanoemulsion-based gel for wound care testing in rats. The results showed that both of the C. chinensis extracts exhibited antioxidant activity when tested using 2,2-Diphenyl-1-picrylhydrazyl (DPPH), ferric reducing antioxidant power (FRAP), and lipid peroxidation inhibition assays. They reduced the expression of IL-1β, IL-6, and TNF-α in RAW264.7 cells induced with lipopolysaccharide (LPS). The ethyl acetate extract also had antibacterial properties. Kaempferol was found in both extracts, whereas hyperoside was found only in the ethanol extract. These compounds were found to be related to the biological activities of the extracts, confirmed via molecular docking. The C. chinensis extract-loaded nanoemulsions had a small particle size, a narrow polydispersity index (PDI), and good stability. Furthermore, the C. chinensis extract-loaded nanoemulsion-based gel had a positive effect on wound healing, presenting a better percentage wound contraction Fucidin cream. In conclusion, this formulation has the potential for use as an alternative wound treatment and warrants further study in clinical trials.

Enhancement in Dissolution Profile of Cilnidipine by Nanonization Technique: Optimization by Box-Behnken design

Objectives: Cilnidipine has limited 25-30% of bioavailability due to BCS class II category drug. The aim of present work was to improve the solubility followed by dissolution rate of cilnidipine by formulation of nanosuspension. Materials and Methods: The nanosuspensionwas developed usingnanoprecipitation techniqueaidingultra-sonication with solvent (Dimethyl sulfoxide), antisolvent (water) and stabilizer (polyvinyl alcohol). The nano formulation was statistically optimized using Design Expert software by theBox-Behnken design. The concentration of Poly Vinyl Alcohol, Volume of Antisolvent and Stirring Time were considered as independent factors whereas Particle size and polydispersity index were considered as dependent factors. Results: The particle size of nanosuspension was found 178.57nm with narrow polydispersity index of 0.130. The microscopy study confirmed amorphous nature particles with rough surface. The zeta potential of 4.55 ±2.78 for optimized formulation finds stability of formulation during storage. The differential scanning calorimetry study and X-ray diffraction pattern showed the crystalline cilnidipine drug was converted to amorphous form upon precipitation into nanoparticles. Due to the nanonization of cilnidipine, the dissolution profile was noted as 92.41±3.56% which was significantly improved as compared with plain drug release data. The stability data showed satisfactory result for 2 months. Conclusion: It is summarized that the nanoprecipitation technique with ultra-sonication is approaching method for the formulation of homogenous nanosuspension with uniform sized dispersion of cilnidipine. Therefore, it can be assumed that the upon the enhancement in dissolution rate, the cilnidipine loaded nanosuspension may lead to improved absorption of drug from intestine followed by significant improvement in bioavailability.

Microemulsions and Nanoemulsions for Topical Delivery of Tripeptide-3: From Design of Experiment to Anti-Sebum Efficacy on Facial Skin.

The targeted delivery of a hydrophilic Tripeptide-3 to the skin using microemulsions or nanoemulsions for facial oil reduction was the focus of this study. The impact factors affecting oil/water transparent dispersion formation, such as the surfactant system, HLB value, and co-solvent, were identified through the water titration method and pseudoternary phase diagram plots. The interfacial tension between caprylic/capric triglyceride (CCT oil) and water was significantly reduced by the surfactant/co-surfactant combination (Smix) of Cremophore® RH40 and a double-tails co-surfactant, polyglycerol-3-diisostearate, at an HLB of 13 together with a water-to-co-solvent (PG) ratio of 1:1. A two-level full factorial design of experiment (FFD-DoE) emphasized the independent variables of the HLB value, co-solvent, and CCT oil contents affecting the optimal compositions for micro- or nanoemulsion formation. The low-energy spontaneous emulsification of the optimized combination at a low Smix content (10%) yielded the translucent oil-in-water Tripeptide-3 nanoemulsions with an internal droplet size of 25.7 ± 1.20 nm, a narrow polydispersity index of 0.237 ± 0.129, and 70.6 ± 0.58% transmittance. The in vitro skin permeation study revealed a significantly higher skin penetration and retention of the Tripeptide-3 nanoemulsions compared to the high surfactant microemulsions and coarse emulsions. Skin irritation and oil control efficacy were evaluated in healthy volunteers before and after product application for 28 days. The obtained nanoemulsions not only decreased sebum production but also enhanced skin moisture levels. In conclusion, the meticulously designed nanoemulsions, incorporating suitable excipients, show a promising delivery system for hydrophilic peptides to control sebum overproduction in oily facial skin.

From monomer to polymer: Controlled synthesis and comprehensive analysis of poly(p-phenylene vinylene) via ROMP

This study focuses on synthesis and evaluation of [2.2] paracyclophane-1,9-diene to produce a soluble poly(p-phenylenevinylene) (PPV) derivative homopolymer using ring-opening metathesis polymerization (ROMP). The resulting homopolymer displayed a narrow polydispersity index (PDI) of 1.22, indicating precise control over polymerization. The PPV derivative exhibited excellent solubility in various organic solvents. Photophysical properties, including optical absorption and fluorescence emission spectra, were investigated to evaluate utilization in optoelectronic devices. Optical band gaps ranged from 2.21 to 2.25 eV for thin films and 2.07 to 2.19 eV for solutions, while the electrochemical band gap, determined by cyclic voltammetry, was 2.37 eV. These materials demonstrated promising fluorescence activity in various solvents and thin films, suggesting potential applications in organic light-emitting diodes (OLEDs) and related optoelectronic devices.

Abstract 3208: A nano sized system for the treatment of gastrointestinal cancers

Abstract Despite the recent progress in cancer immunotherapies, most patients do not benefit from the currently available immune checkpoint blockers, and many develop severe immune-related adverse events. Therefore, it is urgent to develop alternative, effective immunotherapeutic approaches. An example of non-responsive cancers are gastrointestinal (GI) cancers, which account for 26% of the global cancer incidence and 35% of all cancer-related deaths. In many GI cancers, the failure of immunotherapies to yield clinical response is partially attributed to the inefficient antigen presentation by DC, which results in insufficient T cell stimulation despite their expression of tumor-associated antigens (TAA). To overcome these hurdles, we designed novel polymeric-based nanoparticles (NP) to deliver a combination of GI cancers antigens of CEACAM5 protein and toll-like receptor ligands to DC. We chose to encapsulate CEACAM5 antigens because it is overexpressed in GI cancers, such as gastric cancer, colorectal cancer, and pancreatic cancer. With this approach, we aim to modulate the tumor milieu-immune cell interactions to an anti-cancer phenotype in order to control tumor growth and improve overall survival. Our NP present an average diameter below 200 nm, narrow polydispersity index, slightly negative surface charge, spherical morphology, and high antigens and immune potentiators loading. Cy5-labeled NPs were found to be extensively internalized by DC, which triggered their activation in vivo, shown by the increasing expression of DC-related co-stimulatory molecules such as CD80, CD86, and CD40. Furthermore, we assessed the immunotherapeutic effect of our NP on mouse models and on a human 3D multi-cellular spheroid ex-vivo model, composing the patient’s tumor cells and peripheral blood mononuclear cells (PBMC). We found that the NP successfully induced a potent immune-mediated anti-tumor response against CEACAM5-positive GI tumors, sensitizing the tumor microenvironment to other therapies and decreasing tumor volume, ultimately leading to prolonged survival. Taken together, the developed NP induced a strong antigen-specific immune response and overall sensitized CEACAM5-expressing GI cancers to the clinically relevant treatments in vivo, that so far have shown limited clinical outcomes in addition to a specific T cell anti-tumor activity that was shown on our patient-derived ex vivo model. Citation Format: Daniella Vaskovich, Rita Acúrcio, Ron Kleiner, Barbara Carreira, Ana Matos, Helena Florindo, Ronit Satchi-Fainaro. A nano sized system for the treatment of gastrointestinal cancers [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 3208.

The effect of 3D printed microfluidic array designs on the preparation of liposome nanoparticles

In this study Digital Light Processing (DLP) was used to manufacture microfluidic arrays with complex geometries for the fabrication of stable liposome nanoparticles. For the purposes of the study three different microfluidic array designs were 3D printed featuring herringbone structures.The effect of the herringbone numbers and the length of the microfluidic channels on the formation of liposomes was investigated by varying the Total Flow Rate (TFR) and the Flow Rate Ratio (FRR). Laser diffraction analysis showed the production of liposomes with reproducible particle sizes and narrow polydispersity index. The obtained particle size was affected by the TFR (3, 5 and 10 ml/min) and FRR (8:2 and 6:4) varying from 40 to 90 nm. However, the number of herringbone structures in the printed microfluidic arrays demonstrated no significant variations on the liposome particle sizes. Stability studies of the formed nanoparticles showed no changes for the 8:2 FRR and small increase of 8–10 nm for the 6:4 respectively. Overall, the study demonstrated the 3D printing capabilities for the printing of complex microfluidic arrays and the successful engineering of liposomes.

Extraction and characterisation of kudzu root residue lignin based on deep eutectic solvents.

Lignin has great potential as the most abundant renewable phenolic polymer. Studies have shown that lignin structure varies depending on different sources and different extraction methods. However, there are few studies on lignin in kudzu root residue. The aim of the study was to explore optimal extraction conditions of Pueraria lobata residue lignin (PLL) with deep eutectic solvents (DESs) and characterise the structure and morphology of PLL. Firstly, the chemical composition of kudzu root residue was determined by the Van-soest method. Then, betaine was used as hydrogen bond acceptor (HBA), nine kinds of common acids and alcohol were selected as hydrogen bond donor (HBD) to synthesise a DES to extract lignin from kudzu root residue. The influence of conditions on the extraction of PLL was explored by a betaine-based DES according to a single-factor experiment, and then the best process of PLL extraction was determined by an orthogonal experiment. Finally, the morphology and structure of PLL were analysed by scanning electron microscope (SEM), thermogravimetric analysis (TGA), gel permeation chromatography (GPC), Fourier transform infrared spectroscopy (FTIR), and NMR. Cellulose, hemicellulose, lignin, and ash content in kudzu root residue were 41.13%, 16.39%, 25.03%, and 0.41%, respectively. When the DES consisted of betaine and formic acid, the solid-liquid ratio was 1:45, the extraction time was 5.5 h at 160°C, the extraction yield of lignin was 89.29%, and the purity was 83.01%. PLL was composed of interconnected spherical particles with good thermal stability and narrow polydispersity index (PDI) distribution. FTIR and 2D-heteronuclear singular quantum correlation (HSQC) NMR illustrated that PLL was a typical G-type and S-type lignin. This study would fill the gap of research on lignin in kudzu root residue and provide a theoretical reference for the utilisation of lignin in kudzu roots as well as a new thinking for the recycling of kudzu root resources.

Succinylated starch emulsified Eugenol and Carvacrol nanoemulsions improved digestive stability, bio-accessibility and Salmonella typhimurium inhibition

The ultrasonically processed Eugenol (EU) and Carvacrol (CAR) nanoemulsions (NE) were successfully optimized via response surface methodology (RSM) to achieve broad spectrum antimicrobial efficacy. These NE were prepared using 2 % (w/w) purity gum ultra (i.e., succinylated starch), 10 % (v/v) oil phase, 80 % (800 W) sonication power, and 10 min of processing time as determined via RSM. The second order Polynomial method was suitable to RSM with a co-efficient of determination >0.90 and a narrow polydispersity index (PDI) ranging 0.12–0.19. NE had small droplet sizes (135.5–160 nm) and low volatility at high temperatures. The EU & CAR entrapment and heat stability (300 °C) confirmed by Fourier transform infrared spectroscopy (FTIR) and thermogravimetric analysis (TGA). Further, the volatility of EU & CAR NE was 18.18 ± 0.13 % and 12.29 ± 0.11 % respectively, being lower than that of bulk/unencapsulated EU & CAR (i.e., 23.48 ± 0.38 % and 19.11 ± 0.08 %) after 2 h at 90 °C. Interestingly, both EU & CAR NE showed sustained release behaviour till 48 h. Their digest could inhibit Salmonella typhimurium (S. typhimurium) via membrane disruption and access to cellular machinery as evident from SEM images. Furthermore, in-vivo bio-accessibility of EU & CAR in mice serum was up to 80 %. These cost-effective and short-processed EU/CAR NE have the potential as green preservatives for food industry.