Development Of New Methods For The Analysis Of Vitamin B And Plant Hormones

Vitamin B mainly contains thiamine（B1）,riboflavin（B2）,niacin（B3）,panthothenic acid（B5）,pyridoxine,and pyridoxal（B6）,folic acid（B9）,biotin（B8）and B12.They are usually involved in the metabolism of proteins,sugars and proteins in the form of coenzyme.When the body lacks vitamin B,its corresponding function will be blocked and lead to a series of diseases.The human body can’t synthesize vitamin B,need to be obtained through the daily diet and supplement drugs,However,due to the limited supervision of the pharmaceutical market,there will be a phenomenon of serious discrepancies between the value of drug labeling and the actual content,there is an urgent need to develop a method to detect vitamin B supplements in a variety of vitamin B content,to ensure the healthy operation of the body.Chromatographic technique has caused wide public concern because of the advantages of simple operation,good repeatability,sensitive and rapid analysis.So,we established HPLC method for vitamin B tablets by B1,B2,B3,B6 qualitative and quantitative analysis.Plant hormones as a kind of trace organic compounds play an important role in plant metabolism and regulate plant growth.Plant hormones can also be divided into auxin,cytokinin（CK）,gibberellin（GA）,abscisic acid（ABA）,polyamines,ethylene,jasmonic acid,salicylic acid and brassinolide and they can be synthesized in plants.However,because of the characteristics of "high efficiency and little quantity" of plant hormones,it is difficult to use HPLC to detect plant hormones directly in plants.Therefore,qualitative and quantitative analysis of plant hormones in plants has become the bottleneck of plant research.Based on the above problems,we established a d SPE pretreatment method with SiO₂@GO as extractant,hrough the purification and enrichment of plant hormones,combined with HPLC-MS method to complete the separation and analysis of plant hormones.1.A method for simultaneous analysis of four water-soluble B vitamins in Vitamin B Table by HPLC was developed in this research paper.The samples were separated on a ZORBAX Eclipse Plus C18（4.6 mm×100 mm,3.5 μm）reversed phase column with gradient elution.The mobile phase was composed of methanol and acetate buffer（p H value was adjusted to 3.22 by acetic acid）with different ratio.The detection wavelength was set at 270 nm and injection volume was 5 μL,the linear correlation coefficients were between 0.9988 and 0.9999 in the range of 0.8 to 400 μg/m L.The adding standard recovery of compounds ranged from 87.7% to 103.3% with the relative standard deviations were less than 0.33%.The established method was applied to quantitative analysis of vitamin B1,B2,B3 and B6 in the vitamin B Tablet,and the results were satisfied.2.The preparation of SiO₂ @GO composite materials.In this study,GO was prepared by Hummers method,and was successfully coated on the surface of the amino modified SiO₂.We used TEM,SEM,FT-IR to characterize the obtained material,the result showed that the SiO₂@GO material had been successfully synthesized.The prepared GO composite was used as the extractant of d SPE to study the adsorption properties of the target analytes.The effects of the best material to liquid ratio,p H value,adsorption and desorption time,desorption temperature and desorption solvent on the adsorption performance were investigated.The experimental results show that the d SPE method established in this study has good stability and reproducibility,the extraction efficiency was above 80% and the enrichment factor up to 100 times,Which can be used for the extraction of trace enrichment of analytes..3.In this research,a method based on graphene oxide@SiO₂（SiO₂@GO）nanocomposite as adsorbent of dispersive solid-phase extraction（d SPE）combined with high performance liquid chromatography（HPLC）for the analysis of four plant hormones in Arabidopsis,tomato,pear,cucumber and ginger was established.The method was used a Eclipse XDB-C8（4.6 mm×250 mm id,5 μm particle size）reversed phase column.The proportion of mobile phasewas methanol（phase B）: acetate buffer（phase A）= 30:70（p H value was adjusted to 3.22 by acetic acid）.The contents of four kinds of plant hormones were measured at the wavelength of 280 nm,and the NAA of Arabidopsis thaliana and its culture medium were qualitatively analyzed by HPLC-MS.The test results showed that,for the four phytohormones,all calibration curves exhibited good linearity,with R>0.9999 in the range of 0.5-50 μg/m L.The sensitivity was evaluated by determining the LODs were 0.03⁰.05 μg/m L based on a signal-to-noise ratio（S/N）of 3.The recovery rate of tomato samples was between 91.8%¹06.9% under the three adding levels of 5.0,10.0,20.0 μg/m L with RSD lower than 0.8%.The sensitivity of the detection method can be increased by 10-100 times compared with that without SiO₂@GO nano materials and realize the trace analysis of plant hormones in plants.