The aim of the present study was to evaluate the diverse properties of transferrin (Tf)-conjugated nanostructured lipid carriers (NLCs) prepared using three different fatty amines, including stearylamine (SA), dodecylamine (DA) and spermine (SP), and two different methods for Tf coupling. Etoposide-loaded NLCs were prepared by an emulsion-solvent evaporation method followed by probe sonication. Chemical coupling of NLCs with Tf was mediated by an amide linkage between the surface-exposed amino group of the fatty amine and the carboxyl group of the protein. The physical coating was performed in a Ringer-Hepes buffer medium. NLCs were characterized by their particle size, zeta potential, polydispersity index, drug entrapment percentage, drug release profiles and Tf-coupling efficiency. The cytotoxicity of NLCs on K562 acute myelogenous leukaemia cells was studied by MTT assay, and their cellular uptake was studied by a flow cytometry method. SA-containing NLCs showed the lowest particle size, the highest zeta potential and the largest coupling efficiency values. The drug entrapment percentage and the zeta potential decreased after Tf coupling, but the average particle size increased. SP-containing formulations released their drug contents comparatively slower than SA- or DA-containing NLCs. Unconjugated NLCs released moderately more drug than Tf-NLCs. Flow cytometry studies revealed enhanced cellular uptake of Tf-NLCs compared to unconjugated ones. Blocking Tf receptors resulted in a significantly higher cell survival rate for Tf-NLCs. The highest cytotoxic activity was observed in the chemically coupled SA-containing nanoparticles, with an IC(50) value of 15-fold lower than free etoposide.

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Piroxicam is a nonsteroidal anti-inflammatory drug that is practically insoluble in water. The oral absorption rate of piroxicam is dependent on its dissolution rate in the GI tract. The aim of this study was to enhance the dissolution of piroxicam by a microcrystallization technique. The preparation of microcrystals of piroxicam was done by two methods, solvent change and pH shift. In the solvent-change method, the drug was dissolved in acetone, and the stabilizer was dissolved in water. The aqueous phase was added to acetone under homogenization in an ice bath for 1 min. In the pH-shift method, the drug and stabilizer were both dissolved in 0.1 N NaOH (pH 12) using homogenization. The pH was adjusted to 3 using 0.1 N hydrochloric acid. Dissolution testing was carried out in a hydrochloric acid medium using the rotating basket method. Particle size and morphology, FTIR, DSC, XRD, and surface area of the microcrystals were studied. The effects of drug and stabilizer concentration and homogenization rate on particle size and dissolution efficiency were studied statistically using a D-optimal design. The dissolution efficiency in both methods was increased about 3-to 4-fold. The particle size in both methods was decreased in comparison with untreated drug. Maximum dissolution and minimum particle size were obtained by the solvent-change method. According to the results, both microcrystallization methods are effective in the modification of the crystalline the habit of piroxicam.

Rationale Compounds in the taxane drug family are among the most successful and effective chemotherapeutic agents used in the treatment of solid tumors, such as breast, ovarian, and prostate cancers. The tandem mass spectrometric (MS/MS) fragmentation behavior of these compounds is described in detail, and a generalized MS/MS fingerprint is established for the first time. Methods Five compounds, namely paclitaxel, docetaxel, cabazitaxel, cephalomannine, and baccatin III, were evaluated. A hybrid quadrupole orthogonal time‐of‐flight (Q‐TOF) mass spectrometer was used to obtain accurate mass measurements, whereas MS/MS and second‐generation MS/MS (MS3) analyses were performed using a triple quadrupole‐linear ion trap mass spectrometer. Both instruments were equipped with an electrospray ionization source operated in the positive ion mode. Results All taxanes showed an abundant singly charged [M + H]+ species in the single‐stage analysis with mass accuracies less than 3 ppm. The evaluated compounds exhibited common fragmentation behavior in their MS/MS analysis, which allowed for the production of a universal fragmentation pattern. MS3 experiments confirmed the genesis of the various product ions proposed in the fragmentation pathway. In addition, diagnostic product ions were originated from a cleavage in the ester bond between the core diterpene ring structure and the side chain. Conclusions Varying functional groups present in these compounds resulted in unique product ions that are specific to each structure. The established MS/MS fingerprints will be used in the near future for identification and for the development of multiple reaction monitoring liquid chromatography–MS/MS quantification methods.

An effective single-dose vaccine that protects the dam and her suckling offspring against infectious disease would be widely beneficial to livestock animals. We assessed whether a single-dose intramuscular (i.m.) porcine epidemic diarrhea virus (PEDV) vaccine administered to the gilt 30 days post-breeding could generate mucosal and systemic immunity and sufficient colostral and mature milk antibodies to protect suckling piglets against infectious challenge. The vaccine was comprised of polymeric poly-(lactide-co-glycolide) (PGLA)-nanoparticle (NP) encapsulating recombinant PEDV spike protein 1 (PEDVS1) associated with ARC4 and ARC7 adjuvants, a muramyl dipeptide analog and a monophosphoryl lipid A (MPLA) analog, respectively (NP-PEDVS1). To establish whether prior mucosal exposure could augment the i.m. immune response and/or contribute to mucosal tolerance, gilts were immunized with the NP-PEDVS1 vaccine via the intrauterine route at breeding, followed by the i.m. vaccine 30 days later. Archived colostrum from gilts that were challenged with low-dose PEDV plus alum was used as positive reference samples for neutralizing antibodies and passive protection. On day 100 of gestation (70 days post i.m. immunization), both vaccinated groups showed significant PEDVS1-specific IgG and IgA in the serum, as well as in uterine tissue collected on the day of euthanasia. Anti-PEDVS1 colostral IgG antibody titers collected at farrowing were significantly higher relative to the negative control gilts indicating that the NP vaccine was effective in contributing to the colostral antibodies. The PEDVS1-specific colostral IgA and anti-PEDVS1 IgG and IgA antibodies in the mature milk collected 6 days after farrowing were low for both vaccinated groups. No statistical differences between the vaccinated groups were observed, suggesting that the i.u. priming vaccine did not induce mucosal tolerance. Piglets born to either group of vaccinated gilts did not receive sufficient neutralizing antibodies to protect them against infectious PEDV at 3 days of age. In summary, a single i.m. NP vaccine administered 30 days after breeding and a joint i.u./i.m. vaccine administered at breeding and 30 days post-breeding induced significant anti-PEDVS1 immunity in systemic and mucosal sites but did not provide passive protection in suckling offspring.