microsampling in education: training pharmacy students

A unique course at Ghent University in Belgium educates undergraduate pharmacy students on how to apply microsampling in the field of bioanalysis. This blog from Ghent University faculty Members describes the course and the reasons behind it.

In the past few years, the interest in microsampling in the field of bioanalysis has been steadily growing. To acquaint the bachelor's degree students enrolled in the Faculty of Pharmaceutical Sciences at Ghent University (UGent, Belgium) with these developments, we updated one of our practical courses by including microsampling. This allows us to link education, research (microsampling is a research topic in several UGent labs), and service work in clinical laboratories. At the same time, it allows us to introduce pharmacy students to alternative sampling techniques using different biological samples. This is achieved within the context of the Practical Course in Bioanalysis, supervised by Prof. Dr. Marthe De Boevre, which integrates the expertise of three bioanalytical labs at our faculty:

1. The Laboratory of Medical Biochemistry and Clinical Analysis
2. The Centre of Excellence in Mycotoxicology and Public Health
3.  The Laboratory of Toxicology, which is the lab supervising the microsampling training as part of the Practical Course.

Learning How to Analyze Several Compounds in a Range of Biological Matrices

The goal of the Practical Course in Bioanalysis is to introduce the students, who are in the final year of their Bachelor’s Degree Program, to the analysis of several compounds (e.g. medicinal drugs, mycotoxins and other toxicological compounds) in a variety of biological matrices, including:

• Whole blood
• Plasma
• Urine
• Milk
• Pharmaceutical wastewater

Multiple analytical techniques are used, including thin layer chromatography, HPLC-UV, LC-MS/MS and GC-MS. Furthermore, different sample preparation techniques are executed, including liquid-liquid extraction, solid phase extraction and protein precipitation. The aim is threefold:

1. To make the students acquainted with the different analytical techniques
2. To give them insight into the different principles underlying (selective) extraction and chromatographic analysis of compounds
3. To understand and critically appraise obtained analytical results with focus on quality control

Introducing Volumetric Absorptive Microsampling

In 2021, we decided to update the Practical Course to also include a novel sampling technique, namely volumetric absorptive microsampling using the Mitra^® device based on VAMS^® technology. This decision was made based on our research interest in microsampling and because we believe that this technique is (and will further evolve to be) a valuable addition or replacement to the current gold-standard used in most care systems: liquid blood/plasma sampling.

From a patient's perspective, conventional liquid blood draws are often experienced as invasive and unpleasant. We believe that microsampling may be a more suitable specimen collection method in certain specific cases, such as in a home-sampling context or for vulnerable populations, such as children.

Study in Practice: Microsampling in the Lab

PhD students of the Laboratory of Toxicology who supervised the microsampling training

In this specific part of the Practical Course the students had to quantify paracetamol in a dried blood microsample (from VAMS) using a validated method that had been previously published. In short, the students had to extract two VAMS samples (using paracetamol-spiked whole blood), which were then detected and quantified via LC-MS/MS. In addition to calculating the paracetamol concentrations, the students had to evaluate whether both extractions yielded a similar result as part of quality control.

Collecting Finger-Stick Blood Samples

Demonstration of VAMS sampling after finger-stick

We also gave the students the opportunity to try and use a Mitra^® device on themselves to self-collect a blood sample via a finger-stick. This option was purely voluntary, and it turned out to be a highly educational experience. Most of the students were very enthusiastic about it, mainly because of the fact that the finger-stick technique can also be used in clinical practice and is already being used extensively for both research and service work purposes.

For example, the Laboratory of Toxicology at Ghent University runs an ISO 17025-accredited method for the routine determination of alcohol consumption using the direct alcohol marker phosphatidylethanol (PEth). The finger-stick microsampling part of the course also exposed students to ongoing research activities using dried blood, which is relevant in the broader context of their education.

In an effort to get honest feedback about the end-user experience using Mitra devices with VAMS, the course assistants distributed a short questionnaire to the students who had volunteered to self-collect a blood sample via finger-stick. They responded anonymously to questions such as, "How did you experience the use of VAMS to sample blood instead of a conventional blood draw?" and "Do you think that this part of the practical course is relevant to your education as a pharmacist? If yes, why?"

Overall, the feedback from students was positive, including the following responses:

"[VAMS] is a very rapid technique to sample blood. And perhaps the most important experience, I was not scared since the sampling procedure does not include needles."

"Drugs and drug concentrations can easily be monitored in blood using microsamples. I think it is very relevant to come in contact with multiple sampling techniques during our education as a pharmacist."

"It is quite a simple technique. You don’t have to be an expert to know how to sample blood using VAMS."

Practical Applications for Microsampling in Pharmaceutical Sciences & Toxicology

In the past few years, we have used different microsampling approaches (including the collection of conventional dried blood spots (DBS) on filter paper or using alternative finger-stick sampling devices, such as the hemaPEN^®, Capitainer-B or Mitra^® device) for a multitude of applications. Our microsampling studies are primarily situated in the field of toxicology and therapeutic drug monitoring (TDM). The analytes of interest range from proteins (e.g., Hemoglobin A1c, a glycemic marker) to trace elements and small molecules, including:

• Caffeine
• Paracetamol
• Therapeutic drugs (e.g., anti-epileptics or oncology drugs)
• Vitamins
• Mycotoxins

Real-World Examples of Microsampling in Action

We consider microsampling as a helpful tool when aiming for easy follow-up with patients or for performing large-scale population studies. Furthermore, we believe that portable microsampling methods are helpful for studies that involve participants self-sampling at home or that occur in remote settings in low- and middle-income countries where specialized transport and storage are challenging and resources are limited.

For example, we will be using the Mitra^® device in a first exposome study that will be conducted in a rural setting in Burkina Faso, Africa, targeting neonates and their mothers. Also, in the upcoming year we will be using the Mitra device in a large-scale home-sampling study in Belgium to determine the overall PEth (an alcohol biomarker) and vitamin B1 status in a healthy adult population. Without microsampling, such studies would be a real logistical challenge, if not impossible. 

The Future of Microsampling 

When asked if they thought that microsampling might play an important role in the future, the pharmacy students had some interesting thoughts and ideas:

"[Microsampling] definitely can play an important role in the future. This technique of blood sampling is more comfortable for patients. It also saves a lot of time. Perhaps, a blood sample can be collected in a community pharmacy, making this a more accessible and comfortable setting compared to a doctor’s visit."

"[The finger-stick] technique (and microsampling in general) may be useful when a lot of blood samples need to be taken from a patient."

Authors contributing to this guest blog include Prof. Dr. Marthe De Boevre, Prof. Dr. Christophe Stove, and their Course Assistants Liesl Heughebaert, Sigrid Deprez, and Laura Boffel. For additional information about the Faculty of Pharmaceutical Sciences at Ghent University in Belgium, please visit their website.

To read study papers published by this research group and others, please visit our Technical Resource Library.