Synthesis of Sulfur-Based Biocompatible Nonionic Surfactants and Their Nano-Vesicle Drug Delivery

Investigating the self-assembling of nicotinic hydrazide-based amphiphile into nano-range vesicles and its amphotericin B loading applications

Most of the drugs are hydrophobic and have low water solubility, therefore posing issues in their absorption and bioavailability. Nonionic surfactants improve the solubility of hydrophobic drugs by entrapping them in their lipid bilayers. Two nonionic surfactants NODNH-16 and NODNH-18 are synthesized and characterized using different techniques i.e. EI-MS, ¹H NMR, and FTIR. These newly synthesized surfactants were screened for blood hemolysis assay and cell toxicity studies using the NIH/3T3 cell line to assess their biocompatibility. Then amphotericin B was loaded into niosomal vesicles, and the drug entrapment efficiency of these surfactants was measured using UV-visible spectroscopy. The morphology of drug-loaded niosomes of synthesized surfactants was investigated using AFM, and their size, polydispersity, and zeta potential were measured with the Zetasizer instrument. Finally, a simulation study was performed to determine the pattern of self-assembly of the synthesized amphiphiles. Both synthesized nonionic surfactants showed good entrapment efficiency of 60.65 ± 2.12% and 68.45 ± 2.12%, respectively. It was also confirmed that both these synthesized nonionic surfactants were safe and biocompatible and showed less blood hemolysis (i.e. 21.13 ± 2.11% and 23.32 ± 2.45%) and higher 3T3 cells' viability at 150 µg/mL concentration as compared to Tween®-80. The antifungal potential of amphotericin B-loaded niosomes has been evaluated against unicellular multi-fungal species, which showed a promising potential for fungicidal activity. These results are substantiated by constructing a safe vehicle system for drug delivery.

Synthetic star shaped tetra-tailed biocompatible supramolecular amphiphile as an efficient nanocarrier for Amphotericin B

Macrocycle-based amphiphiles are capable of self-assembling into multidimensional nano-architecture with defined dimensions for various applications. Herein we report the synthesis, physio-chemical characterizations and oral drug delivery profiling of resorcinarene-based amphiphilic supramolecular macrocycle. The macrocycle was synthesized in two-step reaction and characterized using ¹H NMR, Mass spectrometry and IR spectroscopic techniques. The synthesized macrocycle was assessed for vesicles formation, checked for biocompatibility and then Amphotericin B (Amp-B) was entrapped in macrocycle-based vesicles. The drug loaded vesicles were characterized for shape, size, homogeneity, drug entrapment, surface charge, in-vitro release profile and stability. Amp-B loaded macrocycle based vesicles were examined in rabbits for in-vivo bioavailability and compared with plan drug suspension. The synthesized macrocycle was non-toxic in normal mouse fibroblast cells, compatible with blood and safe in mice. The drug loaded macrocycle based vesicles appeared spherical with 279.4 nm size and - 12.2 mV zeta potential loading 85.45 % drug. The drug loaded vesicles storage stability for 30 days and gastric fluid stability for 1 h were it retained nearly 90 % drug at 30th day and 83.79 % drug at 1 h in gastric fluid. Oral bioavailability of Amp-B in rabbits was markedly enhanced when delivered in synthesized macrocycle based vesicles in comparison with plan drug suspension. Results of this study indicate that the synthesized star shaped tetra-tailed supramolecular amphiphile could be used as an efficient nanocarrier for enhancing oral bioavailability of drugs with solubility and bioavailability issues like Amp-B.

Synthesis, characterization and drug delivery application of Dapsone based double tailed biocompatible nonionic surfactant

The increase in antimicrobial resistance has created a crisis that has become top priority for global policy and public health. Antibiotics are constantly being rendered in-effective due to the emergence of bacterial resistance; therefore, novel strategies for improving therapeutic efficacies of existing drugs must be focused. Advancements in nanotechnology have opened up new avenues for enhancing therapeutic efficacy of existing drugs via construction of intelligent and efficient delivery systems. This study reports the synthesis of Dapsone based nonionic surfactant and its utilization as delivery system for Ceftriaxone sodium. The synthesized nonionic surfactant was characterized via mass spectrometry and ¹H NMR and IR spectroscopic techniques. The drug loaded vesicles of newly synthesized sulfur based nonionic were formed through thin film hydration method and characterized for drug entrapment efficiency, vesicles size, zeta potential, morphology using UV-vis spectrometry, dynamic light scattering (DLS) and atomic force microscopic (AFM) techniques. The biocompatibility of newly synthesized surfactant was assessed using blood hemolysis and in-vitro cells cytotoxicity. Antibacterial potential of drug loaded vesicles was assessed in gram positive and gram negative bacterial cultures. The spectroscopic results confirm successful synthesis of novel sulfur based nonionic surfactant that formed spherical shaped drug loaded vesicles with an average size of 97.95 ± 3.45 nm and 56.3 ± 3.15 % entrapment of the model drug (Ceftriaxone sodium). The vesicles displayed negative surface charge of -16.8 ± 3.72 mV and released the entrapped drug in a controlled way in-vitro drug release. The drug loaded vesicular formulation showed enhanced cellular uptake and greater antibacterial potentials when compared with control. Results of this study show that the Dapsone based surfactant is safe, biocompatible, non-toxic and can be used as promising vesicular carrier for enhancing therapeutic efficacy of antibacterial drug, Ceftriaxone sodium.

Synthesis of lactobionic acid based bola-amphiphiles and its application as nano-carrier for curcumin delivery to cancer cell cultures in-vitro

Curcumin is highly effective against various types of cancers; however, its low aqueous solubility, high metabolism and non-specificity hinder its efficacy. This study reports the synthesis of three lactobionic acid containing bola-amphiphiles and their investigation for curcumin nano-vesicular delivery into cancer cells. Synthesized bola-amphiphiles were capable of forming nano-vesicles and curcumin loading in a lipophilicity dependent manner. Bola-amphiphile with higher lipophilicity (C12) caused 89.55 ± 5.52% drug encapsulation in its spherical shape nano-vesicles (195.90 ± 0.83 nm). Bola-amphiphile resulting increased curcumin encapsulation with minimum vesicles size was further investigated for cellular uptake and in-vitro anticancer activity. Anticancer activity of curcumin significantly increased against the tested cancer cells upon loading in bola-amphiphile nano-vesicles. Furthermore, nano-vesicular drug delivery of curcumin enhanced its cellular uptake even at the lowest concentration of 1.25 µg/mL.It is concluded that the synthesized bola-amphiphile based nano-vesicles can efficiently deliver curcumin to the tested cancer cells and needs to be tested for established anticancer drugs against different cancer cell lines for effective treatment of cancer.

Biocompatibility of Biomaterials for Nanoencapsulation: Current Approaches

Nanoencapsulation is an approach to circumvent shortcomings such as reduced bioavailability, undesirable side effects, frequent dosing and unpleasant organoleptic properties of conventional drug delivery systems. The process of nanoencapsulation involves the use of biomaterials such as surfactants and/or polymers, often in combination with charge inducers and/or ligands for targeting. The biomaterials selected for nanoencapsulation processes must be as biocompatible as possible. The type(s) of biomaterials used for different nanoencapsulation approaches are highlighted and their use and applicability with regard to haemo- and, histocompatibility, cytotoxicity, genotoxicity and carcinogenesis are discussed.

Synthesis of Nitrogen Containing Biocompatible Non-ionic Surfactants and Investigation for Their Self-Assembly Based Nano-Scale Vesicles

Nonionic surfactants are increasingly interesting because of the solubility and release of drugs. Here, a synthesis of four nonionic nitrogen-containing surfactants is reported. In the synthesis, sulfonamide was reacted with alkyl halides of different lipophilicity. The synthesized nonionic surfactants were characterized by 1H NMR and mass spectroscopy. Their critical micelle concentration (CMC) was determined with a UV spectrophotometer. The self-assembly of surfactants to form drug-loaded, niosomal vesicles with Simvastatin as model drug was investigated. The resulting niosoaml vesicles were characterized by atomic force microscope (AFM), zeta-sizer, and UV spectrophotometer for shape, size, polydispersity index, zeta potential, and drug inclusion efficiency. Their biocompatibility has been determined by blood hemolysis and cell toxicity tests. The synthesized surfactants showed low CMC values and were able to form nano-sized round niosomal vesicles with a homogeneous population and surface negativity. Depending on the lipophilicity, they absorbed an increased amount of drug. The biocompatibility studies show that the surfactants are hemocompatible and non-toxic. The results of the study confirm that the synthesized nonionic surfactants are suitable for the solubilization and release of hydrophobic drugs as efficient novel biocompatible carriers.

Preliminary investigation of novel tetra-tailed macrocycle amphiphile based nano-vesicles for amphotericin B improved oral pharmacokinetics

Supramolecular macrocycles-based drug delivery systems are receiving wider recognition due to their self-assembly into nanostructures with unique characteristics. This study reports synthesis of resorcinarene-based novel and biocompatible amphiphilic supramolecular macrocycle that self-assembles into nano-vesicular system for Amphotericin B (Am-B) delivery, a model hydrophobic drug. The macrocycle was synthesized through a two-step reaction and was characterized with 1H NMR and mass spectrometric techniques. Its biocompatibility was assessed in cancer cell lines, blood and animals. Its critical micelle concentration (CMC) was determined using UV spectrophotometer. Am-B loaded in novel macrocycle-based vesicles were examined according to their shape, size, surface charge, drug entrapment efficiency and excepients compatibility using atomic force microscope (AFM), Zetasizer, HPLC and FT-IR spectroscopy. Drug-loaded vesicles were also investigated for their in-vitro release, stability and in-vivo oral bioavailability in rabbits. The macrocycle was found to be nontoxic against cancer cells, haemo-compatible and safe in mice and revealed lower CMC. It formed mono-dispersed spherical shape vesicles of 174.4 ± 3.78 nm in mean size. Vesicles entrapped 92.05 ± 4.39% drug and were stable upon storage with gastric-simulated fluid and increased the drug oral bioavailability in rabbits. Results confirmed novel macrocycle as biocompatible vesicular nanocarrier for enhancing the oral bioavailability of lipophilic drugs.