Apparent formation constant (K), enthalpy (ΔH⁰), entropy (ΔS⁰), and standard free energy (ΔG⁰) changes of β-CD: berberine hydrochloride complex as a function of temperature.

<p>Apparent formation constant (K), enthalpy (ΔH⁰), entropy (ΔS⁰), and standard free energy (ΔG⁰) changes of β-CD: berberine hydrochloride complex as a function of temperature.</p

Influence of excipients normally used in the tablets formulation (tolerance error ± 5.0%).

<p>Influence of excipients normally used in the tablets formulation (tolerance error ± 5.0%).</p

Influence of pH on the fluorescent intensity of the complex C = 2.00 µg/mL, C_β-CD = 1.00×10⁻³ mol/L, λ_ex/λ_em = 431/540 nm.

<p>Influence of pH on the fluorescent intensity of the complex C = 2.00 µg/mL, C_β-CD = 1.00×10⁻³ mol/L, λ_ex/λ_em  =  431/540 nm.</p

Analytical characteristics of the method.

a<p>The number of data for each calibration graph correspond to 8 different concentration levels, with three replicates for each level.</p>b<p>The standard deviation obtained from a series of 11 blanks solutions.</p>c<p>Limit of detection calculated according to IUPAC definitions: 3S⁰/K, where K is the slope of the calibration graph.</p>d<p>Limit of quantification calculated according to the IUPAC definition: 10S₀/K.</p>e<p>Relative standard deviation obtained from a series of 11standards each containing 0.50 µg ml⁻¹berberine hydrochloride.</p

Determination of berberine hydrochloride in tablets (n = 5, p = 95%).

<p>Determination of berberine hydrochloride in tablets (n = 5, p = 95%).</p

Fluorescence emission spectra.

<p>C_β-CD: from top to bottom(1–8):0.0, 2.0,4.0,6.0,8.0,10.0,12.0, 14×10⁻⁴ mol/L. pH = 9.00, C_{berberine hydrochloride} = 2.00 µg/mL.</p

The structure of CD oligosaccharide.

<p>The structure of CD oligosaccharide.</p

Effect of the β -CD concentration.

<p>C_{berberine hydrochloride} = 2.00 µg/mL, pH = 9.00.</p

The recoveries of the determination of berberine hydrochloride in tablets.

<p>The recoveries of the determination of berberine hydrochloride in tablets.</p

1/(F-F₀)versus 1/C_β-CD².

<p>1/(F-F₀)versus 1/C_β-CD².</p