Adsorption of Methylene Blue from Aqueous Solution onto Perlite

Adsorption of methylene blue from aqueous solutionsonto unexpanded and expanded perlite samples activatedby H₂SO₄ and NaCl solutions has beeninvestigated, to assess the possibility of usingperlite for removing cationic dyes from aqueoussolutions. The effects of pH and temperature of dyesolution on the adsorption capacities have beenevaluated. The experimental data were correlatedreasonably well by the Langmuir adsorption isothermand the isotherm parameters (Q _m and K) have beencalculated. The removal efficiency (P) anddimensionless separation factor (R) have shown thatperlite can be used for removal of methylene blue fromaqueous solutions, but unexpanded perlite is more effective.     

Pharmacokinetics of Sulpiride After Intravenous,Intramuscular, and Oral Single-Dose Administration in Nurse Mares

Sulpiride (SLP) is an antipsychotic drug used in humans. Although no pharmacokinetic data are available for horses, it is commonly used to encourage ovulation in noncycling mares and to stimulate lactation in adoptive mares. The aim of this study is to assess the pharmacokinetics profile of SLP after intravenous (IV), intramuscular (IM), and oral (PO) administrations in normal horses. Animals (n = 6) were treated with 1 mg/kg SLP, administered by IV, IM, and PO routes according to a randomized crossover design (3 × 3 Latin square). Blood samples (5 mL) were collected at a programmed time and analyzed using a validated with fluorescence detection method. SLP was present at a detectable concentration up to 24 hours postadministration for all routes, except for one animal in the PO group. IV and IM administrations gave similar curves, with an IM average bioavailability of 118.0%. These high values were mainly the result of the profile generated by two horses, in which a secondary concentration peak occurred in the terminal phase of the curve. After PO administration, AUC_0-∞, and consequently bioavailability (20.4%), was low. This finding could be owing to the physicochemical features of the drug. Indeed, considering that SLP is a weak base, existing in the ionized form at gastric and physiological pH, it is unsurprising that it is poorly absorbable, especially in horses with a particularly acidic gastric pH. In conclusion, injective routes are definitely preferable to PO dosing because of the low bioavailability using this route.