Dispersive solid-phase extraction based on zirconium metal-organic framework coupled with gas chromatography-mass...

Sugar phosphates (SPx) play important role in the metabolism of the organism. SPx such as glycerate 3-phosphate, fructose 6-phosphate and glucose 6-phosphate in biological samples have the poor stability, similar structure and low abundance, which make their separation and detection more challenging.

UiO-66-NH₂ and ZrO₂ coated SiO₂(SBA-15) hard-core-shell adsorbents (UiO-66-NH₂@SBA-15 and ZrO₂@SBA-15) were synthesized, which were further used for dispersive solid-phase extraction for enriching the SPx in biological samples. The protocol was developed by UiO-66-NH₂@SBA-15 and ZrO₂@SBA-15 coupled with gas chromatography-mass spectrometry for the detection of trace SPx. The univariate experiment and response surface methodology were used to optimize the adsorption and desorption conditions.

The adsorbents showed excellent adsorption capacity and specificity towards SPx, which were proved by adsorption and selective experiments. Under the optimized conditions, there were good linearity within the range of 5.0-5000.0 ng mL^-1, low limits of detection (0.001-1.0 ng mL^-1), low limits of quantification (0.005-5.0 ng mL^-1) and good precision (relative standard deviation less than 14.7 % for intra-day and inter-day). The satisfactory recoveries (89.1-113.8 %) and precision (0.5-14.6 %) were obtained when the sorbents were used to extract SPx from serum, saliva and cell samples. Moreover, UiO-66-NH₂@SBA-15 was applied to the quantitative analysis of SPx from gastric cancer patients, because of a higher adsorption capacity (169.5-196.1 mg g^-1).

UiO-66-NH₂@SBA-15 showed great potential in the extraction of SPx in biological samples, which was beneficial to find out the metabolic change of SPx and explain the pathogenesis of the disease.