Development and Characterization of Florfenicol-Loaded BSA Nanoparticles as Controlled Release Carrier.

Florfenicol (FLO) is a broad-spectrum fluorinated antibiotic used for the treatment of bacterial diseases such as bovine respiratory disease (BRD) in cattle. FLO is a poorly soluble drug in aqueous solution, and its encapsulation in various nanovehicles has been reported to be less than 30%. In this context, the use of bovine serum albumin (BSA) as a nanocarrier for FLO is an interesting approach. BSA is a biocompatible, biodegradable, nontoxic, and nonimmunogenic natural protein, allowing the vehiculization of hydrophilic and hydrophobic drugs with a well-tolerated administration. The present work focuses on the fabrication and characterization of florfenicol-loaded BSA (FLO-BSA NPs), incorporation efficiency, and in vitro release pattern. FLO-BSA NPs nanoparticles were successfully obtained by a simple, low-cost and in a few steps method. The physicochemical properties of the obtained nanoparticles such as size (~ 120 nm), polydispersity index (0.04), and zeta potential (approximately - 40 mV) suggest a high colloidal stability and suitable characteristics for drug delivery. The drug loading reveals a high incorporation of florfenicol in the nanoparticles, in which 33.6 molecules of FLO are encapsulated per each molecule of BSA. The in vitro release profile exhibits an initial stage characterized by the burst effect and then a prolonged release of FLO from the albumin matrix, which is compatible with the Higuchi model and which follows a Fickian diffusion. The results together suggest a suitable tool for future investigations in drug delivery field in order to use this nanomaterial in food, pharmaceutical, and veterinary industry.

A novel no-carrier-added submicromolar scale radiosynthesis of [S-methyl-14C]-florfenicol.

In this paper is reported a novel reaction scheme for the no-carrier-added submicromolar scale radiosynthesis of [S-methyl-(14)C]-florfenicol that has been newly designed, developed and employed by us successfully. The [(14)C]-product was obtained in an overall radiochemical yield of 30% based on [(14)C]-methyl iodide taken for the reaction with a radiochemical purity of more than 96%. The specific activity of the product was ~50 mCi (1.85 GBq)/mmol. Chlorosulfonation of compound I was followed by sodium salt formation in situ and it was succeeded by the introduction of [(14)C]-methyl group by coupling with [(14)C]-CH3 I. Subsequently, the oxazolidin-2-one protecting group was opened up by a reaction with sulfuric acid in dioxane and later, the amino group was dichloroacetylated with methyl-2,2-dichloroacetate in triethylamine to obtain [S-methyl-(14)C]-florfenicol.

[Synthesis and tests of antibacterial activity of new analogs of d(+)-threo-1-(p-methylsulphonylphenyl)-2-dichloroacetamido-1,3-propanediol (thiamphenicol)]. / Sintesi ed indagini sulla attività antibatterica di nuovi analoghi del D(+)-treo-1-(p.metilsolfonilfenil)-2-dicloroacetamido-1,3-propandiolo (tiamfenicolo).

The synthesis of three new analogues of D(+)-threo-1-(p.methylsulphonylphenyl)-2-dichloroacetamido-1,3-propanediol (thiamphenicol) (I) which are D(--)-threo-2-(p.toluensulfophonamido)-1-(p.methylsulphonylphenyl)-1,3-propanediol (II), D(--)-threo-2-(p.aminobenzensulphonamido)-1-(p.methylsulphonylphenyl)-1,3-propanediol (III), D(--)-threo-2-(p.acetamidobenzensulphonamido)-1-(p.methylsulphonylphenyl)-1,3-propandiol (IV) is reported. The antibacterial activity of the compounds obtained was estimated in comparison with (I) in vitro and the therapeutic activity in vivo by experimental infection of the rat. The results showed the total absence of both types of activity.