Is HPLC an effective method to determine caffeine content?

The applicability of the proposed method was evaluated to analyze of caffeine from different tea and energy drink samples. These results showed that the microextraction method coupled with HPLC is a powerful method for determining caffeine in various samples (Table 4).

Why caffeine is used for HPLC calibration?

If you mean the use of caffeine to check UV wavelength accuracy, lots of chromatographers prefer to use it over holmium oxide filters (or use it in addition to) because caffeine has both a local min & max in the UV range that’s at least close to the wavelengths commonly used on a daily basis.

Which method is used to determine caffeine content?

HPLC is the method of choice by many researchers in determining the caffeine contents of beverages, tea leaves and coffee beans.

What is the retention time for caffeine?

Doubling the flow rate to 0.86 mL/min reduces the run time to 2 minutes and the elution time of caffeine to 0.988 minutes.

Why is HPLC accurate?

With many steps involved, the precision of HPLC is largely down to the process being automated and therefore highly reproducible. HPLC does have low sensitivity for certain compounds, and some cannot be detected as they are irreversibly adsorbed. Volatile substances are better separated by gas chromatography.

What is the difference between validation and calibration?

Validation is a documented program that provides high degree of assurance that a specific process, equipment, method or system consistently produces a result meeting pre-determined acceptance criteria. Calibration ensures that instrument or measuring devices producing accurate results.

How is caffeine used in HPLC calibration?

Sample/standard preparation:

1. Prepare five concentration solution of caffeine, which are 25 ppm, 50 ppm, 100 ppm, 150 ppm, and 250 ppm.
2. Preparation of stock solution : Take 100.0 mg weight of caffeine in 100 ml volumetric flask, dissolve it and dilute up to mark with HPLC grade water.

How is caffeine free calculated?

Many companies measure caffeine in their beverages. They use a method called ultraviolet spectroscopy, Max explains. It measures how much ultraviolet light — light close to violet, but wavelengths that people cannot see — is absorbed by different chemicals.

How do you make a standard solution of caffeine?

A. 1. Prepare a 100 ppm stock solution of caffeine by dissolving 100 mg in 1 L of water. Record the mass used to all the available digits and use volumetric glassware to achieve 4 significant figures of precision. Calculate the actual concentration.

How do I calibrate my HPLC?

CHECKPOINT: LEAKAGE TEST (BY PRESSURE DROP)

1. Ensure that, the instrument is ready for calibration and Start-up procedure is followed.
2. Place inlet tubing of the Pump into the Water HPLC grade through a suction filter.
3. Allow the mobile phase to flow for about 5 min.
4. Block Pump outlet with the block screw.

Is caffeine UV active?

The UV absorption spectrum (see figure below) of caffeine exhibits a pair of absorption bands peaking at 205 nm and 273 nm with a characteristic absorption shoulder between them. Soft drinks contain a wide variety of substances, many of which absorb UV light at 275 nm.

What are the isocratic HPLC standards for caffeine?

Isocratic HPLC system Caffeine standards (50, 100, 150, 200 ppm) 254 nm UV detector 50:50 Methanol:water C 18

Can a biological matrix be used for caffeine quantification?

These results suggest that our analytical method and substitution of biological matrix was linear, precise, and accurate for caffeine quantification and could be used for measuring prenatal exposure and let us to study, in the future, concentration differences observed during apnea clinical treatment. 1. Introduction

Which is the best method for quantification of caffeine?

The analytical methods used for the quantification of caffeine and its main metabolites are immunoassay with monoclonal antibodies, which presents as main disadvantage the selectivity and sensitivity of the method [ 16

How is caffeine measured in human and FBS?

No differences were observed between quantification in human and FBS. This method was applied to quantify plasma drug concentration in mothers and their newborns in a Mexican northeast population. In our study, we confirmed self-reported caffeine maternal intake in 85.2% ( ); meanwhile, in their newborn’s plasma, it was detected only in 78% ( ).