Visual genotyping of thalassemia by using pyrrolidinyl peptide nucleic acid probes immobilized on carboxymethylcellulose-modified paper and enzyme-induced pigmentation

A simple probe pair was designed for the detection of hemoglobin E (HbE) genotype, a single-point mutation that leads to abnormal red blood cells commonly found in South East Asia. The key to differentiation is the use of a conformationally constrained peptide nucleic acid (PNA) that was immobilized on carboxymethylcellulose-modified paper. This was then used for target DNA binding and visualization by an enzyme-catalyzed pigmentation. The biotinylated target DNA bound to the immobilized probe was visually detected via alkaline phosphatase-linked streptavidin. This enzyme conjugate catalyzed the dephosphorylation of the substrate 5-bromo-4-chloro-3-indolyl phosphate, leading to a series of reactions that generate an intense, dark blue pigment. The test was validated with 100 DNA samples, which shows good discrimination among different genotypes (normal, HbE, and heterozygous) with 100% accuracy when optimal conditions of analysis were applied. The method does not require temperature control and can be performed at ambient temperature. This is an attractive feature for diagnosis in primary care, which accounts for a large part of affected population. Graphical abstract Schematic representation of a paper-based sensor for the detection of the gene Hemoglobin E. The interaction between an immobilized peptide nucleic acid and a DNA target leads to enzymatic pigmentation, allowing simple visual readout with up to 100% accuracy.

[1]  A. Ott,et al.  Impact of point-mutations on the hybridization affinity of surface-bound DNA/DNA and RNA/DNA oligonucleotide-duplexes: Comparison of single base mismatches and base bulges , 2008, BMC biotechnology.

[2]  S. Fucharoen,et al.  Prenatal and postnatal diagnoses of thalassemias and hemoglobinopathies by HPLC. , 1998, Clinical chemistry.

[3]  Y. Kan,et al.  The prevention of thalassemia. , 2013, Cold Spring Harbor perspectives in medicine.

[4]  J. Wall,et al.  Reverse dot blot probes for the screening of β‐thalassernia mutationsin Asians and American blacks , 1994 .

[5]  Adisorn Tuantranont,et al.  Electrochemical paper-based peptide nucleic acid biosensor for detecting human papillomavirus. , 2017, Analytica chimica acta.

[6]  T. Vilaivan,et al.  Hybridization of pyrrolidinyl peptide nucleic acids and DNA: selectivity, base-pairing specificity, and direction of binding. , 2006, Organic letters.

[7]  Arif Ali,et al.  Peptide nucleic acid (PNA) — a review , 2006 .

[8]  Yan Hong,et al.  High-throughput beta-thalassemia carrier screening by allele-specific Q-primer real-time polymerase chain reaction. , 2010, Analytical biochemistry.

[9]  J. Clegg,et al.  Thalassemia — a global public health problem , 1996, Nature Medicine.

[10]  Voravee P. Hoven,et al.  Positively charged polymer brush-functionalized filter paper for DNA sequence determination following Dot blot hybridization employing a pyrrolidinyl peptide nucleic acid probe. , 2013, The Analyst.

[11]  T. Mohan,et al.  Selective immobilization and detection of DNA on biopolymer supports for the design of microarrays. , 2015, Biosensors & bioelectronics.

[12]  Darlin Lantigua,et al.  Paper-Based Sensors: Emerging Themes and Applications , 2018, Sensors.

[13]  D. Fan,et al.  Simultaneous detection of target CNVs and SNVs of thalassemia by multiplex PCR and next‑generation sequencing. , 2019, Molecular medicine reports.

[14]  Peter E. Nielsen,et al.  Peptide nucleic acids (PNA) : oligonucleotide analogues with an achiral peptide backbone , 1992 .

[15]  V V Demidov,et al.  Stability of peptide nucleic acids in human serum and cellular extracts. , 1994, Biochemical pharmacology.

[16]  Chien-Fu Chen,et al.  Surface-modified cellulose paper and its application in infectious disease diagnosis , 2018, Sensors and Actuators B: Chemical.

[17]  Voravee P. Hoven,et al.  Filter paper grafted with epoxide-based copolymer brushes for activation-free peptide nucleic acid conjugation and its application for colorimetric DNA detection. , 2019, Colloids and surfaces. B, Biointerfaces.

[18]  S. Fucharoen,et al.  Prenatal diagnosis of β‐thalassaemia by reverse dot‐blot hybridization , 1999 .

[19]  Tom Fawcett,et al.  An introduction to ROC analysis , 2006, Pattern Recognit. Lett..

[20]  Snober Ahmed,et al.  Paper-based chemical and biological sensors: Engineering aspects. , 2016, Biosensors & bioelectronics.

[21]  Shanshan Wang,et al.  Single-Molecule Counting of Point Mutations by Transient DNA Binding , 2017, Scientific Reports.

[22]  T. Vilaivan,et al.  Pyrrolidinyl PNA polypyrrole/silver nanofoam electrode as a novel label-free electrochemical miRNA-21 biosensor. , 2018, Biosensors & bioelectronics.

[23]  S. Fucharoen,et al.  Prenatal diagnosis of beta-thalassaemia by reverse dot-blot hybridization. , 1999, Prenatal diagnosis.

[24]  P. Charoenkwan,et al.  High-resolution melting analysis for prenatal diagnosis of beta-thalassemia in northern Thailand , 2017, International Journal of Hematology.

[25]  H. Orelma,et al.  CMC-modified cellulose biointerface for antibody conjugation. , 2012, Biomacromolecules.

[26]  T. Vilaivan Pyrrolidinyl PNA with α/β-Dipeptide Backbone: From Development to Applications. , 2015, Accounts of chemical research.

[27]  G. Fucharoen,et al.  A simplified screening strategy for thalassaemia and haemoglobin E in rural communities in south-east Asia. , 2004, Bulletin of the World Health Organization.

[28]  O. Chailapakul,et al.  Immobilization-free electrochemical DNA detection with anthraquinone-labeled pyrrolidinyl peptide nucleic acid probe. , 2016, Talanta.

[29]  T. Vilaivan,et al.  Pyrrolidinyl peptide nucleic acids immobilised on cellulose paper as a DNA sensor , 2015 .

[30]  S. Fucharoen,et al.  Hemoglobinopathies in Southeast Asia: molecular biology and clinical medicine. , 1997, Hemoglobin.

[31]  D. Sabath Molecular Diagnosis of Thalassemias and Hemoglobinopathies: An ACLPS Critical Review , 2017, American journal of clinical pathology.

[32]  S. Thein,et al.  Next‐generation sequencing as a tool for breakpoint analysis in rearrangements of the globin gene clusters , 2017, International journal of laboratory hematology.

[33]  S. Chong,et al.  Rapid carrier screening for beta-thalassemia by single-step allele-specific PCR and detection. , 2007, Clinical biochemistry.

[34]  Feng Xu,et al.  A review on advances in methods for modification of paper supports for use in point-of-care testing , 2019, Microchimica Acta.

[35]  X. Gu,et al.  A Review of the Molecular Diagnosis of Thalassemia , 2002, Hematology.