Hindawi
International Journal of Clinical Practice
Volume 2023, Article ID 9593796, 8 pages
https://doi.org/10.1155/2023/9593796
Research Article
Comparison of Modified Manual Acid-Phenol Chloroform
Method and Commercial RNA Extraction Kits for Resource
Limited Laboratories
Samuel Asamoah Sakyi ,1 Alfred Efah ,1,2 Emmanuel Naturinda,2 Ebenezer Senu ,1
Stephen Opoku ,1,3 Benjamin Amoani ,4 Samuel Kekeli Agordzo ,1
Oscar Simon Olympio Mensah ,1 James Grant ,1 Elizabeth Abban ,2,5
Tonnies Abeku Buckman ,1 Alexander Kwarteng,6 Richard K. Dadzie Ephraim,7
and Kwabena Owusu Danquah8
1Department of Molecular Medicine, School of Medicine and Dentistry, Kwame Nkrumah University of Science and Technology,
Kumasi, Ghana
2Department of Medical Diagnostics, Faculty of Allied Health Sciences, College of Health Sciences,
Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
3Division of Clinical Immunology and Rheumatology, University of Alabama at Birmingham, Birmingham, UK
4Department of Biomedical Science, School of Allied Health Sciences, University of Cape Coast, Cape Coast, Ghana
5Department of Medical Laboratory Technology, Garden City University College, Kumasi, Ghana
6Department of Biochemistry and Biotechnology, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
7Department of Medical Laboratory Sciences, Faculty of Allied Health, University of Cape Coast, Cape Coast, Ghana
8Department of Clinical Pathology, Noguchi Memorial Institute for Medical Research, University of Ghana, Accra, Ghana
Correspondence should be addressed to Ebenezer Senu; ebensenu@gmail.com
Received 19 March 2023; Revised 11 May 2023; Accepted 30 May 2023; Published 9 June 2023
Academic Editor: Marta Laranjo
Copyright © 2023 Samuel Asamoah Sakyi et al.Tis is an open access article distributed under the Creative Commons Attribution
License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly
cited.
Background and Aim. RNA extraction is a commonly used technique inmolecular biology. In recent years, commercially available
RNA extraction kits have largely replaced conventional approaches. However, these commercial kits are expensive and are not
readily available in many resource-constrained institutions and laboratories. Tis study therefore compared the performance of
the conventional acid guanidinium thiocyanate-phenol-chloroform (AGPC) extraction method to QIAamp Viral RNAMini Kit
(QIAGEN, Cat. No. 52906) and OxGEn RNA Kit (OxGEn Molecular Solutions, GE-009) to build an in-h®ouse RNA extraction
technique from blood and oral swab samples. Method. In a comparative experimental cross-sectional study, RNA was extracted
from oral swabs and blood samples from 25 healthy individuals at the Department of Molecular Medicine, KNUST. RNA was
extracted by the manual AGPC extraction method and commercial RNA extraction kits. Te quantity (ng/μl) and purities (260/
280 nm) of the extracted RNAwere measured spectrophotometrically using the IMPLENNanoPhotometer N60.Te presence of
RNA in the extracts was confrmed using 2% agarose gel electrophoresis. Statistical analyses were conduc®ted using R language.
Results. Te yield of RNA extracted from blood and oral swab samples using modifed AGPCwas signifcantly higher compared to
the commercial methods (p< 0.0001). However, the purity of RNA extracted by the manual AGPC method from blood was
signifcantly lower than the commercial methods (p< 0.0001). Moreover, the purity from oral swabs using the manual AGPC
method was signifcantly lower compared to QIAamp (p< 0.0001) and the OxGEn kits method (p< 0.001). Conclusion. Te
modifedmanual AGPCmethod has a very high yield of RNA extracts using blood samples, which could serve as an alternate cost-
efective method for RNA extraction in resource-limited laboratories; however, its purity may not be suitable for downstream
2 International Journal of Clinical Practice
processes. Moreover, the manual AGPC method may not be suitable for extracting RNA from oral swab samples. Future in-
vestigation is needed to improve the purity of the manual AGPC RNA extraction method and also confrmation of the obtained
results by PCR amplifcation and RNA purity verifcation by sequencing.
1. Introduction existing traditional extraction procedures in order to get
a sufcient quantity and quality of RNA for downstream
Ribonucleic acid (RNA) is a signifcant macromolecule that processes. In order to develop a proprietary method for RNA
is required for a variety of biological functions, including extraction from blood and oral swab samples, this study
protein synthesis and catalysis of biological reactions. As compares a modifed standard phenol-chloroform extrac-
a result, extracted RNA is commonly employed in molecular tion method to commercially available RNA extraction kits;
biology tests such as gene expression profling using reverse- OxGEn and QIAamp Viral RNA Mini Kit.
transcription quantitative polymerase chain reaction (RT- ®
qPCR) arrays and next generation sequencing [1]. For ef- 2. Materials and Methods
fcient RT-PCR assays, quantitative extraction of nucleic
acids with high purity from complicated samples is required. 2.1. StudyDesignandSetting. Tis comparative experimental
Low extraction efciency could result in distorted signals cross-sectional design was carried out on 25 physiologically
during exponential amplifcation, leading to false negative healthy individuals who consented to participate in the
results [2–4]. Low-quality extractions, on the other hand, study, from July to October 2022. Blood and oral swab
may contain a variety of PCR inhibitors, resulting in er- samples were collected for RNA extraction at the Research
roneous amplifcation readouts [4]. and Development Unit at the Department of Molecular
RNA extraction is usually performed using one of two Medicine, Kwame Nkrumah University of Science and
methods: phenol-chloroform extraction or commercially Technology (KNUST). Te Department of Molecular
available silica spin column extraction. Te use of acid Medicine is under the College of Health Sciences at the
guanidinium thiocyanate-phenol-chloroform to induce School of Medicine and Dentistry.
phase separation of biological mixtures and subsequent
selective isolation of molecules of interest is the basis for 2.2. EthicalConsideration. Ethical approval was sought from
phenol-chloroform-based RNA extraction [1, 5, 6]. Te the Committee on Human Research, Publication and Ethics,
phenol-chloroform-based RNA extraction method is rela- School of Medical Sciences, Kwame Nkrumah University of
tively inexpensive and has higher RNA yield when working Science and Technology (CHRPE/SMS/KNUST) before the
with small quantities of cells or tissues [1]. However, the commencement of the study. Study protocol was thoroughly
traditional phenol chloroform-based extraction method is explained to subjects before sample collection. Written in-
time consuming, may necessitate a large volume of blood formed consent was also sought from participants before
samples, and involves harmful chemical solvents such as sample collection.
phenol and chloroform [7].
In recent years, commercially available RNA extraction
kits have largely replaced conventional RNA extraction 2.3. Sample Collection. Blood and oral swab samples were
approaches. Among them are TRIzol, manufactured by collected from participants for RNA extraction. 2ml of
Termo Fisher Scientifc in Waltham, MA, and QIAzol, venous blood sample was drawn from each participant into
manufactured by QIAGEN in Hilden, Germany [1], ethylene diamine tetraacetic acid (EDTA) tube and stored at
QIAamp® Viral RNA Mini Kit, PureLink RNA Mini Kit 4°C until assayed. Oral swabs were collected into Eppendorf(Invitrogen), OxGEn and UltraClean Microbial RNA Iso- tubes containing 200 μl of phosphate bufered saline (PBS)
lation Kit (MoBio) [8]. Te use of commercial kits neces- and stored at 4°C. RNA was extracted from each sample
sitates fewer blood samples and takes less time than existing using three diferent methods; a modifed manual acid-
traditional techniques [7]. However, commercial systems phenol chloroform RNA extraction method, standard
and kits are costly and are not readily available in many protocol for QIAamp® Viral RNA Mini Kit (QIAGEN, Cat.
countries [1, 9]. Many resource-constrained institutions and No. 52906) and OxGEn RNA Kit (OxGEn Molecular So-
laboratories lack enough or no research funding, making the lutions, GE-009). Agarose gel electrophoresis was performed
use of commercial kits challenging. Even with sufcient to visualize the various RNA extracted.
funding, using commercial kits can be difcult due to delay
in their importation [7]. Phenol-chloroform RNA 2.4. Manual Acid-Phenol Chloroform Method
extraction-based regents can be prepared locally from base
chemicals at low cost [5, 6]. Terefore, to promote the use of 2.4.1. Preparation of Home-Made TRIzol Reagent and RBC
molecular biology tests such as gene expression profling Lysis Bufer. Te reagents involved were prepared in our
using RT-qPCR arrays and next generation sequencing in laboratory under optimum conditions. In the preparation of
developing nations [7], where research is less well funded by a 100ml TRIzol reagent, 38ml of water saturated phenol
local governments and agencies, it is critical to improve (pH 4.3), 5ml glycerol, and 3.33ml sodium acetate
International Journal of Clinical Practice 3
(pH 5, 3M solution) were measured into a falcon tube. Tis bufer AW1 was added to the QIAamp Mini column and
was followed by the addition of 11.82 g guanidine thiocy- centrifuged at 6000×g (8000 rpm) for 1minute. Te col-
anate and 7.61 g ammonium thiocyanate, making a fnal lection tube was discarded and replaced with a clean 2ml
concentration of 0.8M and 0.4M, respectively. Water collection tube. 500 μl of wash bufer AW2 was added to the
(ddH2O) was added to make 100ml. Te components were QIAamp mini column and centrifuged at full speed
mixed by stirring at room temperature until completely (20,000× g; 14,000 rpm) for 3minutes. 60 μl of bufer AVE
dissolved (30–60mins). was used for the elution of the RNA.
2.4.2. Preparation of 10x Lysis Bufer. 89.9 g of NH4Cl, 10.0 g 2.6. Extraction of RNA by OxGEn Kit. Te OxGEn kit is
KHCO3, and 2.0ml of 0.5M EDTA were measured into a spin column-based RNA extraction kit. 560 μl Solution A
a fask and dissolved in 800ml ddH2O, and pH was adjusted was transferred into a 1.5ml microcentrifuge tube, 5 μl of
to 7.3. Te volume was brought to 1 liter and mixed thor- RNA carrier was added, 140 μl of the sample was added to
oughly. Tis solution is stable for 6months at 2–8°C in the tube and mixed by pulse-vortex for 15 s, followed by
a tightly closed bottle. incubation at room temperature. 560 μl of ethanol
(96–100%) was added to the mixture. 650 μl of the lysate was
transferred onto the G-spin column and centrifuged at
2.4.3. Procedure for RNA Extraction by the Manual Acid 8000 rpm for 1minute. Tis step was repeated with the
Phenol Chloroform Method. To 200 μl of sample, 925 μl of remaining lysate until the entire lysate had passed through
the 1X RBC lysis bufer was added and incubated at room the G-spin column. Te column was washed with 600 μl of
temperature for 10mins. Te mixture was centrifuged at solution W1 and centrifuged at 8000 rpm for 1min. Te
1400 rpm for 10mins at 25°C, after incubation. Te super- column was washed with 600 μl of solution W2 followed by
natant was discarded, and 1000 μl of 1X RBC lysis bufer was centrifugation at 13000 rpm for 1minute, and the collection
added to the residue. Te mixture was allowed to stand for tube was replaced with a new one. Te residual wash bufer
5mins at 25°C, followed by centrifugation at 3000 rpm for was removed by centrifuging at 13000 rpm for 2minutes,
2mins at 25°C. 1000 μl of DPBS was added to the residue and and the column was transferred onto a new 1.5ml micro-
centrifuged at 3000 rpm for 2mins at 25°C. Te supernatant centrifuge tube. 50 μl of solution E was added onto the
was discarded, and 1200 μl of the home-made TRIzol was column, followed by incubation for 3min at room tem-
added to the residue to resuspend the cells. 200 μl of perature, RNA was eluted by spinning down at 8000 rpm for
chloroform (CHCl3) was added to the mixture and mixed by 1minute, and RNA was quantifed using the IMPLEN
vortexing for 15 seconds. Te mixture was centrifuged at Nanophotometer.
13,000 rpm for 10mins at 4°C. Te upper phase was
transferred into a new Eppendorf tube, after centrifugation.
Equal volume of cold isopropanol was added to the upper 2.7. Analysis of RNA Extract. Both the concentration and
phase and inverted to mix. Te mixture of the upper phase absorbance ratio at A260/280 nm were measured using the
and isopropanol was placed in a −20°C freezer for 30mins to IMPLEN NanoPhotometer N60. Te concentrations were
enhance precipitation, followed by centrifugation at estimated in ng/μl, followed®by analysis on a 2% agarose gel
13,000 rpm for 10mins at 4°C. Te supernatant was dis- electrophoresis.
carded, and 500 μl of ice-cold 75% ethanol was added to the
pellet and vortexed and allowed to stand for 10mins to rinse
the pellets (75% ethanol was prepared with RNAse-free 2.7.1. Statistical Analyses. Data from the study was entered
water and stored at −20°C). Tis was followed by centri- into Microsoft Excel 2019. Statistical analyses were per-
fugation at 13,000 rpm for 10mins at 4°C. Te supernatant formed on R language for statistical computing [10]. Dis-
was discarded, and the pellets were air dried for 10mins. tribution and levels of RNA concentration and purity
20 μl of RNAse-free H2O was added to the RNA pellet for between blood and oral swabs were present by the kernel
elution. Te RNA was quantifed using IMPLEN density plot and boxplot and the subsequent MannWhitney
NanoPhotometer® N60. U test. Comparison of RNA concentration and purity be-tween the manual AGPC method and the two commercial
extraction kits from blood and oral swabs were represented
2.5. Extraction of RNA by QIAamp RNA Mini Kit. Te by boxplot; Kruskal–Wallis tests and subsequent post-hoc
QIAamp kit is designed for the purifcation of viral RNA tests were used for the statistical comparisons. p value of
from body fuids. In brief, 140 μl of the sample (blood or oral <0.05 was considered statistically signifcant.
swab) was transferred to 560 μl bufer AVL-carrier RNA in
a microcentrifuge tube. Tis was followed by addition of 3. Results
560 μl of ethanol (96–100%) after 10mins of incubation.
630 μl of the solution was transferred to the QIAamp Mini 3.1. Comparison of Both RNA Quality and Yield between
column followed by centrifugation at 6000×g (8000 rpm) for Samples. Figure 1 shows both concentrations (A and C) and
1minute. Te QIAamp Mini column was placed into a clean purity (B and D) of RNA using the manual AGPC RNA
2ml collection tube. Tis step was repeated until all of the extraction method. Of comparison of RNA yield concen-
lysate had been loaded onto the spin column. 500 μl of wash tration between blood samples and oral swabs, blood had
4 International Journal of Clinical Practice
slightly higher yield compared to that of oral swab samples. 3.5. Comparison of Cost Involved in Using theTree Diferent
However, there was no signifcant diference between the Methods. Table 1 shows the cost involved in extracting 50
concentrations of RNA in these samples (p � 0.525) samples using each method. At the time of purchasing the
(Figure 1(c)). Moreover, the purity of RNA was slightly various items, a dollar was equivalent to GH₵ 9.9 Ghana
higher in blood compared to oral swabs, although the purity Cedis. It required $1.85 to prepare 60ml of homemade
of RNA between these two samples was not statistically TRIzol and $3.03 for 500ml of the RBC Lysis bufer required
signifcant (p � 0.740) (Figure 1(d)). for the extraction of 50 sample (25 blood and 25 oral swabs)
using the manual AGPC method. However, an amount of
$314 [11] and $113.04 was required for the extraction of the
3.2. Comparison of Yield and Purity between Methods Using same number of samples by the QIAamp method and the
Blood Samples. In comparison of yields, all the three OxGEn kit, respectively (Table 1).
methods produced signifcantly diferent yields of RNA
extracts from blood samples (p< 0.0001). In a post-hoc test,
the yield using modifedmanual acid phenol chloroformwas 4. Discussion
signifcantly higher compared to the two commercial RNA extraction is usually conducted using one of two
methods (QIAamp method and OxGEn kit) (p< 0.0001). methods: phenol-chloroform extraction or commercially
Moreover, the yield between the QIAamp method and the available silica spin column extraction. In recent years,
OxGEn kit was also signifcantly diferent (p< 0.0001) commercially available RNA extraction kits have largely
(Figure 2(a)). replaced conventional RNA extraction approaches [7].
In comparison of purity, the purity of RNA extracted by However, commercial systems and kits are costly, and they
the manual AGPC method was signifcantly lower than that are not widely available in many countries [1, 9]. Many
extracted by the QIAampmethod (p< 0.0001). However, the resource-constrained institutions and laboratories lack
purity between the manual AGPC and OxGEn kit was enough or no research funding, making the use of com-
similar (p> 0.05). Te QIAamp kit also produced signif- mercial kits challenging. Cost-efectiveness, availability,
cantly higher purity of RNA extracts from that of the OxGEn dependability, and purity are all needs for small laboratories.
kit method (p< 0.0001) (Figure 2(b)). Even with sufcient funding, using commercial kits can be
difcult owing to time constraints and technological limi-
3.3. Comparison of Yield and Purity between Methods Using tations [7]. Moreover, phenol-chloroform RNA extraction-
Oral Swabs. Te yield using the manual AGPC method based reagents can be prepared locally from base chemicals
was signifcantly higher than that of the OxGEn kit at low cost [5, 6]. It is against this background that this study
method (p< 0.0001) using the oral swabs. In addition, the compared the quality and quantity of RNA recovered from
yield produced using the QIAamp kit was signifcantly the modifed manual acid guanidinium thiocyanate-phenol-
higher compared to the concentration of RNA extracted chloroform (AGPC) extraction method and commercial
using the OxGEn kit method using the oral swabs. RNA extraction kits (QIAamp Viral RNA mini kit and
However, the yield using either the manual AGPC method OxGEn kit) to develop a proprietary method for RNA ex-
or the QIAamp kit method was proportional (p> 0.05) traction from both blood and oral swabs. All the reagents
(Figure 3(a)). involved in this manual extraction method were locally
In comparison of purity of RNA extracted, the purity of prepared from their basic chemical constituents.
RNA extracted using the manual AGPC method was sig- In this study, RNA recovered from twenty-fve blood
nifcantly lower compared to using the QIAamp kit samples using the manual AGPC method had the highest
(p< 0.0001) and the OxGEn kit method (p< 0.001). How- concentration of RNA with a median value of 114.40 ng/μl
ever, the RNA extracted using the QIAamp kit method was compared to that of QIAamp (20.4 ng/µl) and OxGEn kit
signifcantly pure than using the OxGEn kit method (5.32 ng/μl). However, the purity (A260/280 ratio) of RNA
(p< 0.0001) (Figure 3(b)). extracted from blood by QIAamp and OxGEn was purer
(≥1.8) compared to that of the modifed manual AGPC
method (≤1.8). Although the QIAamp and OxGEn kit
3.4. Agarose Gel Electrophoresis of RNA Extracts. produced high purity of RNA extracts, both kits do not meet
Following agarose gel electrophoresis, there were strong the demands of cost efectiveness, costing $314 and $113.04,
bands for RNA extracted from blood samples by each of respectively, to extract 50 samples each [11], whereas at an
the three methods; manual AGPC method, QIAamp kit, equivalent price, the manual extraction method can extract
and OxGEn (Figure 4). Visibility of the RNA bands on the over 3000 samples. Surprisingly, the 260/230 ratios de-
gel was comparable between the manual method and the termined by all the three methods were signifcantly lower
commercial methods (QIAamp kit and OxGEn kit), de- than the optimum.Tese low values are usually attributed to
spite diferences in blood RNA concentration produced by salt contamination, despite the fact that the fnal washing
these methods. However, there were no visible bands of step in both extraction methods requires over 70% ethanol
RNA extracted by the manual AGPC method and the wash. Ionic strength, on the other hand, is known to in-
OxGEn kit using oral swab samples (Figures 4(a) and fuence nucleic acid absorbance, particularly at 260 nm,
4(c)), while the QIAamp kit produced faint bands which could have infuenced the 260/230 ratio [12, 13]. For
(Figure 4(b)). oral swab samples, both the manual and the QIAamp
International Journal of Clinical Practice 5
12
0.004
0.003
8
0.002
4
0.001
0.000 0
0 100 200 300 400 1.4 1.5
Manual RNA Concentration (ng/uL) Manual RNA Purity (A260/280)
(a) (b)
400
ns ns
300
1.5
200
1.4
100
0
Blood Sample Oral Swab Sample Blood Sample Oral Swab Sample
(c) (d)
Figure 1: Comparison of RNA concentration (a and c) and purity (b and d) between blood and oral swab samples for the manual AGPC
RNA extraction method; ns: not signifcant.
methods yielded comparable RNA concentrations, with the used. However, the high concentration observed with the
QIAamp mini kit yielding higher purity than both the modifed manual AGPCmethod can be explained by the fact
manual AGPCmethod and the OxGEn kit. In our attempt to that it extracts total RNA from the samples, whereas the
address the issue with purity, various modifcations were QIAamp and OxGEn kits are designed specifcally for viral
made including repeated 75% ethanol wash. However, this RNA extraction. Extracted RNA was verifed by 2% agarose
decreased the concentration of the extract without any gel electrophoresis. For blood samples, RNA recovered by
concurrent increase in the purity, contrasting what was either the manual AGPC or QIAamp method produced
stated in a study conducted by Toni et al. [1]. Te manual comparable visible RNA bands on the gel, despite the dif-
AGPC method’s high yield may be attributed to the larger ferences in concentrations. By contrast, none of the RNA
volume of blood used than that used for the commercial kits, from oral swab RNA extracts by the manual AGPC method
200 μl and 140 μl, respectively. Interestingly, similar volumes and OxGEn produced bands on the gel. RNA extracts by the
of oral swabs were used, but comparable concentrations QIAamp method had faint bands on the gel.
were produced by both the manual AGPC and QIAamp kits. In agreement with the fndings of this study, the manual
As a result, the diference in RNA concentration recovered AGPC RNA extraction method has been demonstrated to
by each method cannot be explained solely by the volumes yield high quantity of RNA compared to column-based kits
density
Manual RNA Concentration (ng/uL)
Manual RNA Purity (A260/280) density
6 International Journal of Clinical Practice
**** **** **** **** ns ****
3.0
200
2.5
100 2.0
1.5
0
Manual AGPC QIAamp Kit OxGEN Kit Manual AGPC QIAamp Kit OxGEN Kit
(a) (b)
Figure 2: Box and Whisker plot of RNA concentration (a) and purity (b) based on the three diferent methods, using blood samples;
∗∗∗∗p< 0.0001, ∗∗∗p< 0.001, ∗∗p< 0.01, and ∗p< 0.05; ns: not signifcant.
400
ns **** *** ******** ****
300
3
200
2
100
0
Manual AGPC QIAamp Kit OxGEN Kit Manual AGPC QIAamp Kit OxGEN Kit
(a) (b)
Figure 3: Box and Whisker plot of RNA concentration (a) and purity (b) based on the three diferent methods, using oral swabs;
∗∗∗∗p< 0.0001, ∗∗∗p< 0.001, ∗∗p< 0.01, and ∗p< 0.05; ns: not signifcant.
including the QIAamp and OxGEn kit using diferent produced conficting results; for example, Xiang et al. found
samples [6, 14, 15]. Several studies have also shown that no signifcant diference in RNA purity between RNeasy,
manual AGPC-based RNA extraction yields 2.4–93 times a silica column-based as QIAamp Viral RNA mini kit and
more RNA than silica column-based protocols [16–18], OxGEn, and manual AGPC using sputum samples, although
which is consistent with our fndings. Additional advantage the later yielded high concentration of RNA [18]. Although
is that since only the aqueous phase which contains prin- the manual AGPC method could yield a high quantity of
cipally RNA after addition of chloroform is used to obtain RNA, this method is time consuming and involves nu-
the fnal RNA, there is low or insignifcant levels of DNA merous steps, which often result in contamination of the
contamination [19]. On the contrary, few studies have RNA. Te use of AGPC to induce phase separation of
Blood Concentration (ng/uL)
Oral Swab Concentration (ng/uL)
Oral Swab Purity (A260/280) Blood Purity (A260/280)
International Journal of Clinical Practice 7
Blood Oral swabs
Blood
oral swab Blood Oral swab
(a) (b) (c)
Figure 4: Gel electrophoresis of RNAs isolated by manual AGPC (a), QIAamp kit (b), and OxGEN kit (c).
Table 1: Tis shows the cost involved in extracting 50 samples Data Availability
using each method.
Item Quantity Price All data generated or analyzed during this study are includedwithin this article. Te data can be obtained from the
Homemade TRIzol 60ml $1.85 (GH₵18.4)
Lysis bufer 500ml $3.03 (GH 30.45) corresponding author upon reasonable request.₵
Total $4.88 (GH₵48.8 )
QIAamp viral RNA kit 1 box $314 (GH₵31 8.81) Conflicts of Interest
OxGEn kit 1 box $113.04 (GH₵1119.1)
Note. Bold values represent signifcant diference at p < 0.0001. Te authors declare that they have no conficts of interest.
biological mixtures and subsequent selective isolation of Acknowledgments
molecules of interest requires toxic reagents such as phenol
and chloroform [1, 6]. Both phenol and chloroform, aside Te authors are grateful to study participants, as well as
posing danger to human health, can remain signifcant research assistants at Research and Development unit,
contaminants in RNA extraction. Te presence of these Department of Molecular Medicine, KNUST, who con-
contaminants may have an impact on both the RNA tributed in diverse ways to the successful implementation of
quantifcation on spectrophotometers and the results of the study.
subsequent experiments.
Furthermore, the lack of signifcance in comparing References
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