ライフサイエンスコーパス: dried blood spot

1 0x, was occasionally observed with FFPET and dried blood spot.

2 ne and more sensitive for CMV detection than dried blood spots.

3 he microscope) and another one consisting of dried blood spots.

4 innate immune function, measured in neonatal dried blood spots.

5 genomic DNA obtained from Guthrie cards with dried blood spots.

6 , amitriptyline, lidocaine, and sunitinib in dried blood spots.

7 agnosis of HIV infection in infants by using dried blood spots.

8 ar dystrophy by the creatine kinase level on dried blood spots.

9 R method to detect HIV type 1 (HIV-1) DNA in dried blood spots.

10 o the measurement of transferrin receptor in dried blood spots.

11 oxoplasma-specific immunoglobulin M (IgM) in dried blood spots.

12 nd tenofovir diphosphate concentrations from dried blood spots.

13 sing tenofovir diphosphate concentrations in dried blood spots.

14 s, and a SARS-CoV-2 serosurvey conducted via dried blood spots.

15 here is no biomarker currently detectable in dried blood spots.

16 weeks 1, 6, 14, 26, 38, and 50 postpartum on dried blood spots.

17 h concentrations of tenofovir diphosphate in dried blood spots.

18 he authors measured EDA in serum, saliva and dried blood spots.

19 d by tenofovir diphosphate concentrations in dried blood spots.

20 tively correlated with CMV viral load in the dried blood spots.

21 he active metabolite, in cervical tissue and dried blood spots 1 month after each ring insertion.

22 100 person-years if drug was not detected in dried blood spots, 2.3 infections per 100 person-years i

23 1 pg/mL (3.47 pmol/L), total testosterone in dried blood spots (8-10 muL) with a LLOQ of 40 pg/mL, an

24 TGW had comparable TFV-DP concentrations in dried blood spots after 4 weeks of directly observed dai

25 combining materials originally designed for dried blood spot analysis with stable isotope dilution a

26 ospital in Kampala, Uganda, and obtained for dried blood spot analysis.

27 ssess nevirapine exposure was developed from dried blood spot and plasma nevirapine concentrations at

28 storage at room temperature, the punched out dried blood spot and the foam was dissolved in 300 muL o

29 We obtained archived residual dried blood spots and data for nearly all IEM cases from

30 noassay (ELISA) for quantifying insulin from dried blood spots and demonstrate its application in a l

31 ultiplex assay of 10 enzymatic activities in dried blood spots and fibroblast lysates that allow newb

32 ds itself to samples such as tumor biopsies, dried blood spots and fluids including urine and CSF to

33 d on tenofovir diphosphate concentrations in dried blood spots and genotypic resistance were assessed

34 of samples enriched for proviral DNA such as dried blood spots and increased use of next-generation s

35 ment with activity data determined from both dried blood spots and serum samples, giving an informati

36 TFV-DP in dried blood spots and sex hormones in serum were measure

37 the recent improvements for accurately using dried blood spots and the imminent appearance to the mar

38 ssess inflammatory marker levels in neonatal dried blood spots and their association with later risk

39 say (ELISA) for quantifying adiponectin from dried blood spots and then demonstrate its application i

40 omplexes from biological substrates, such as dried blood spots and thin tissue sections, by use of na

41 n or sonication) of the paper containing the dried blood spots, and acidification of extraction solve

42 g, ART drug concentrations in urine, plasma, dried blood spots, and hair) have been associated with h

43 measured levels of tenofovir diphosphate in dried blood spots; and (3) examine patterns of risk beha

44 Cotinine levels in dried blood spots are an accurate biomarker of maternal

45 The archived dried blood spots are an important and precious resource

46 Drug concentrations in dried blood spots are strongly correlated with protectiv

47 n umbilical cord blood to assess cotinine in dried blood spots as a biomarker of maternal smoking clo

48 hown by their performance in reactions using dried blood spots as the enzyme source.

49 al resistance genes in respiratory fluid and dried blood spots, but FLASH-NGS is applicable to all ar

50 milk protein) were analyzed in eluates from dried blood spots by enzyme-linked immunosorbent assay.

51 of Hb variants by direct surface sampling of dried blood spots by use of an Advion Triversa Nanomate

52 Dried blood spots can be used for comprehensive, untarge

53 f serum ferritin and transferrin receptor in dried blood spots can be used to facilitate the identifi

54 s determined by polymerase chain reaction on dried blood spots collected at 6 and 12 weeks of age.

55 DNA was obtained from dried blood spots collected at birth as part of routine

56 sphate in 61% (125/201) of randomly selected dried blood spots collected at the first follow-up visit

57 Anti-S1 antibodies were measured from dried blood spots collected between February 2021-August

58 extracts from human whole blood samples and dried blood spots collected on chromatography paper.

59 ent and validation of a at-home finger-prick dried blood spot collection kit and an analysis method.

60 Blood volume in dried blood spot (DBS) analysis is assumed to be constan

61 A fixed area punch in dried blood spot (DBS) analysis is assumed to contain a

62 The use of dried blood spot (DBS) and dried urine spot (DUS) sample

63 Comparison of Aptima results for paired dried blood spot (DBS) and plasma specimens archived fro

64 As a part of data collection, dried blood spot (DBS) and urine samples are being colle

65 s of this study were to develop and validate dried blood spot (DBS) assays for the quantification of

66 Dried blood spot (DBS) cards are often used to bridge th

67 Dried blood spot (DBS) cards support these efforts, but

68 Since March 2004, we obtained 2135 dried blood spot (DBS) citrulline samples from 57 intest

69 aneously sequence 100 targets and applied to dried blood spot (DBS) controls and field isolates from

70 A dried blood spot (DBS) is a well-accepted means for the

71 oof-of-concept study combining water-soluble dried blood spot (DBS) material in liquid chromatography

72 The dried blood spot (DBS) matrix has significant utility fo

73 Dried blood spot (DBS) newborn screening (NBS) amino aci

74 Monitoring by dried blood spot (DBS) provides patients the opportunity

75 ated with the bioanalytical methods used for dried blood spot (DBS) sample analysis.

76 Dried blood spot (DBS) sample collection has been sugges

77 ogeneity issues associated with conventional dried blood spot (DBS) sample when a subpunch is taken.

78 [25(OH)D3] concentrations in stored neonatal dried blood spot (DBS) samples are associated with pedia

79 t for highly versatile automated analyses of dried blood spot (DBS) samples by commercial capillary e

80 To improve EID services in Ukraine, dried blood spot (DBS) samples obtained from 237 HIV-exp

81 Dried blood spot (DBS) samples on filter paper are surgi

82 limit of detection (LLOD) for Aptima HCV on dried blood spot (DBS) samples was calculated to be 2.43

83 A total of 24,227 dried blood spot (DBS) samples were collected from 82 pr

84 variants and modified species extracted from dried blood spot (DBS) samples with virtually no sample

85 gh-Resolution Melting (MS-HRM) approach from dried blood spot (DBS) samples, assessing the different

86 irect quantitative bioanalysis of drugs from dried blood spot (DBS) samples, using an MS detector, wi

87 e useful for online cleanup of extracts from dried blood spot (DBS) samples.

88 rine) in physiological solutions, urine, and dried blood spot (DBS) samples.

89 oglobulin can be measured in either serum or dried blood spot (DBS) samples.

90 here is an increasing interest in the use of dried blood spot (DBS) sampling and multiple reaction mo

91 The potential of dried blood spot (DBS) sampling as an alternative for cl

92 Dried blood spot (DBS) sampling is a promising method fo

93 Dried blood spot (DBS) sampling is recognized as a valua

94 Dried blood spot (DBS) self-sampling removes the need fo

95 We instituted dried blood spot (DBS) specimen monitoring of citrulline

96 Blood samples were collected as dried blood spot (DBS) specimens from all participants f

97 Dried blood spot (DBS) specimens were tested for neutral

98 d has gained substantial experience with the dried blood spot (DBS) technique as an alternative.

99 The dried blood spot (DBS) technique can be used to collect,

100 costs, and simplified shipping and storage, dried blood spot (DBS) techniques have faced adoption re

101 Dried blood spot (DBS) technology is believed to be a vi

102 ess agreement between CRP values obtained by dried blood spot (DBS) versus conventional venepuncture

103 Dried blood spot (DBS), dried plasma spot (DPS), and pla

104 se of umbilical cord (UC) tissue and newborn dried blood spot (DBS)-extracted genomic DNA (gDNA) as a

105 (CO), and black carbon (BC), and collecting dried blood spots (DBS) and urinary samples for biomarke

106 Dried blood spots (DBS) are an alternative specimen type

107 Dried blood spots (DBS) are often used as a less invasiv

108 Since dried blood spots (DBS) are routinely collected for meta

109 Dried blood spots (DBS) are simpler to prepare, store, a

110 Drug concentrations in hair and dried blood spots (DBS) are used to assess long-term-exp

111 Dried blood spots (DBS) are useful for molecular assays

112 tly hinder the development and acceptance of dried blood spots (DBS) as a widely used quantitative bi

113 etroviral therapy (ART) guidelines recommend dried blood spots (DBS) as an alternative specimen type

114 expression was measured by RNA sequencing of dried blood spots (DBS) collected at baseline and 5 week

115 the MAS assay to determine subtype B DRMs in dried blood spots (DBS) collected from patients on antir

116 Dried blood spots (DBS) collected onto filter paper have

117 The use of dried blood spots (DBS) could ameliorate many problems o

118 lovirus (CMV) load in finger-stick-collected dried blood spots (DBS) could potentially be useful for

119 ranulocytes isolated by magnetic sorting and dried blood spots (DBS) derived from 50 mul of periphera

120 l TDF/FTC, completed interviews and provided dried blood spots (DBS) for measurement of tenofovir-dip

121 and robust LC-MS/MS-based enzyme assay using dried blood spots (DBS) for the diagnosis of pyridox(am)

122 system for online extraction and analysis of dried blood spots (DBS) from DBS paper cards to a multid

123 We tested 617 dried blood spots (DBS) from human immunodeficiency viru

124 alytical strategy for multiomics analysis of dried blood spots (DBS) has been developed, featuring pr

125 Dried blood spots (DBS) have been used as alternative sp

126 ucting HIV Early Infant Diagnosis (EID) from dried blood spots (DBS) in low- to middle-income countri

127 Although tenofovir diphosphate (TFV-DP) in dried blood spots (DBS) is a predictor of adherence and

128 Tenofovir diphosphate (TFV-DP) in dried blood spots (DBS) is associated with viral suppres

129 phosphate (TFV-DP) concentration measured in dried blood spots (DBS) is used to monitor cumulative ad

130 ed a method for analyzing perchlorate in the dried blood spots (DBS) of newborns.

131 rug concentrations in clinical studies using dried blood spots (DBS) on paper, rather than convention

132 l for PoC-EID testing, using fresh blood and dried blood spots (DBS) samples at obstetric health faci

133 e, we examined the stability of HIV-1 DNA in dried blood spots (DBS) stored in humid heat and at -20

134 al mercury (THg) and methylmercury (MeHg) in dried blood spots (DBS) though more research is required

135 ulin G levels based on participant-collected dried blood spots (DBS) to assess the cumulative inciden

136 2 diagnostic tests using minimal amounts of dried blood spots (DBS) to identify high-risk CHD compar

137 ulfatase A (ARSA) activity in leukocytes and dried blood spots (DBS) using deuterated natural sulfati

138 etection (LOD) of the new test in plasma and dried blood spots (DBS) was determined with the 2nd Inte

139 In total, dried blood spots (DBS) were collected from 276 individu

140 test (RDT, n = 11,351), and NAIIS collected dried blood spots (DBS) which were later tested for hist

141 HIV genotyping from dried blood spots (DBS) with noncommercial (in-house) as

142 s for inborn errors of metabolism (IEM) from dried blood spots (DBS) with quality assurance.

143 he serum samples and 40-10,000 pg/mL for the dried blood spots (DBS) with R(2) >0.998.

144 fingerstick placed on filter paper (known as dried blood spots (DBS)) is more advantageous.

145 measure IFX in 100-fold diluted extracts of dried blood spots (DBS), and LOD achieved was below 2 ng

146 inoadipic acid (alpha-AAA) in plasma, serum, dried blood spots (DBS), urine and dried urine spots (DU

147 frica for early infant diagnosis of HIV from dried blood spots (DBS), viral load monitoring with this

148 Dried blood spots (DBS)-based drug resistance testing, w

149 ermination of methotrexate polyglutamates in dried blood spots (DBS).

150 improve the analysis of therapeutic drugs in dried blood spots (DBS).

151 ity and yield of DNA extracted from neonatal dried blood spots (DBS).

152 bias would facilitate more widespread use of dried blood spots (DBS).

153 (n = 20), cerebrospinal fluid (CSF; n = 36), dried blood spots (DBS; n = 104), and dried plasma spots

154 ve developed and applied a broadly sensitive dried-blood-spot (DBS)-based genotyping assay for survei

155 nalysis of targeted drugs and metabolites in dried blood spots (DBSs) and whole mouse thin tissue sec

156 n California, 3,252,156 infants had DNA from dried blood spots (DBSs) assayed for T-cell receptor exc

157 em mass spectrometry (tandem-MS) analysis of dried blood spots (DBSs) collected at birth can identify

158 Dried blood spots (DBSs) could circumvent many logistica

159 In 1 of 4 provinces, we also collected dried blood spots (DBSs) for plasma HIV RNA testing.

160 try can identify metabolite abnormalities in dried blood spots (DBSs) from affected patients, with th

161 an observational cohort study using data and dried blood spots (DBSs) from the Breastfeeding, Antiret

162 The importance of dried blood spots (DBSs) has increased in medical care.

163 Dried blood spots (DBSs) have gained increasing attentio

164 Dried blood spots (DBSs) have had a long history in dise

165 easible in resource-limited settings, use of dried blood spots (DBSs) is being adopted.

166 orm that enables fully automated analyses of dried blood spots (DBSs) is proposed by the at-line coup

167 nfirmed infections and mailed self-collected dried blood spots (DBSs) to a central lab.

168 Ten dried blood spots (DBSs) were assembled that contained P

169 Dried blood spots (DBSs) were collected to estimate sero

170 Dried blood spots (DBSs), collected for the newborn scre

171 Whole genome amplification of dried blood spot DNA has been used to provide DNA for ge

172 DNA is more robust than genotyping amplified dried blood spot DNA, is comparable in cost, and can be

173 require robust, high-accuracy genotyping of dried blood spot DNA.

174 ol to erythronate in stable isotope-assisted dried blood spot experiments.

175 ure requires a simple extraction step from a dried blood spot followed by the quantification of produ

176 analysis used genomic DNA extracted from the dried blood spot followed by whole genome amplification

177 screening by creatine kinase (CK) levels in dried blood spots followed by mutation detection in thos

178 However, homogenization of the dried blood spots, followed by a 24 h exposure to solven

179 ls who consented to participation and gave a dried blood spot for HIV testing at 12 months.

180 s for Chlamydia trachomatis nucleic acid and dried blood spots for C. trachomatis antibodies.

181 provinces provided anonymous survey data and dried blood spots for HIV serostatus assessment.

182 experiences, and 1,220 (70.2%) also provided dried blood spots for HIV testing.

183 (MS/MS) based assays of lysosomal enzymes in dried blood spots for the early detection of Pompe, Fabr

184 rams used elevated creatine kinase levels in dried blood spots for the initial screening, with the di

185 blood for the Determine and Vikia tests and dried blood spots for the reference standard test (AxSYM

186 ) were tested for malarial parasitemia using dried blood spots from 12, 24, and 36 weeks of age.

187 resentative household survey which collected dried blood spots from 15,125 asymptomatic individuals a

188 a Genetic Disease Screening Program provided dried blood spots from 428 newborns delivered in 2001-20

189 was then compared with microscopy using 891 dried blood spots from a cohort of 77 Ugandan children f

190 APPs were measured in eluates from neonatal dried blood spots from cases, controls, and siblings usi

191 We analyzed 911 dried blood spots from Ghana (n = 165), Tanzania (n = 17

192 fter birth, trained research staff collected dried blood spots from infants during a heel stick proce

193 e (PPT1) and tripeptidyl peptidase (TPP1) in dried blood spots from newborns using tandem mass spectr

194 d by measuring immunoreactive trypsinogen on dried blood spots (from April 1985 through June 1991) or

195 complexity are high, DNA was extracted from dried blood spots, genes of interest were amplified, amp

196 tive tenofovir diphosphate concentrations in dried blood spots (>700 fmol/dried blood punch).

197 d, we found that measurements of cotinine in dried blood spots had high sensitivity (92.3%) and speci

198 The use of dried blood spots has increased in research and clinical

199 hensive acyl-specific lipidomic profiling of dried blood spots has yet to be examined.

200 ction and transportation of samples, such as dried blood spots, has improved test accessibility, the

201 ration sequencing of FFPET, whole blood, and dried blood spot in the evaluation of inherited CV disor

202 essfully quantified fasting adiponectin from dried blood spots in 13,329 of 13,879 (96%) children.

203 Paediatricians collected dried blood spots in a follow-up of 13,879 fasted childr

204 Creatine kinase (CK) levels are increased on dried blood spots in newborns related to the birthing pr

205 red glucocerebrosidase enzymatic activity in dried blood spots in patients with Parkinson's disease (

206 e measured drug concentrations in plasma and dried blood spots in seroconverters and a random sample

207 and SARS-CoV-2 antibody measurement (paired dried blood spots) in all household members.

208 erval, 19%-47%) by increasing DNA input from dried blood spots into polymerase chain reaction.

209 genetic material, including cheek swabs and dried blood spots, is described briefly.

210 ive specimen types and technologies, such as dried blood spots, may address these issues and increase

211 ted blood specimens from newborns, stored as dried blood spots, may provide a low-cost method to obje

212 crolimus levels were assessed by a validated dried blood spot method for sampling and measurement.

213 llected by the patients themselves using the dried blood spot method.

214 specimen type (FFPET versus whole blood and dried blood spot; n=12).

215 Measured dried blood spot nevirapine concentrations were higher t

216 T-cell receptor excision circles (TRECs) in dried blood spots obtained at birth permits population-b

217 The authors analyzed archival dried blood spots obtained from newborns to assess wheth

218 pproximately 3 microL of blood) punched from dried blood spots obtained from: i) whole blood standard

219 ss FMR1 methylation in DNA isolated from the dried blood spots of 36,124 deidentified newborn males.

220 markers of T and B cell numbers in neonatal dried blood spots of 99 children with cCMV and 54 childr

221 hods have been developed for the analysis in dried blood spots of steroids and lysosomal enzymes.

222 egy for detection of malaria parasites using dried blood spots offers a sensitive and efficient appro

223 uantitative analysis of enzyme activities in dried blood spots on newborn screening cards has emerged

224 ildren in Western Kenya, in the form of both dried blood spots on Whatman filter paper, and the blood

225 We used dried blood spots once every 6 months provided by partic

226 which accounted for a total of 10,871 paired dried blood spot:plasma data points.

227 lied its own cutoff of interpret results for dried blood spots prepared from either adults with serol

228 HAT patients and 619 endemic controls and on dried blood spots prepared with plasma of 95 gHAT and 37

229 ncubation of enzyme-specific substrates with dried blood spot punches or fibroblast lysate followed b

230 tyrosine, phenylalanine, and methionine on a dried blood spot requiring a 2 min run.

231 We obtained punch samples from dried blood spots routinely collected from HIV-exposed i

232 s, behaviours, and service use and to give a dried blood spot sample that was tested anonymously for

233 At the final study visit, a dried blood spot sample was obtained for viral load and

234 ve SARS-CoV-2 antibodies in their postpartum dried blood spot sample.

235 s HIV infection status, as determined by the dried blood spot sample.

236 te test efficacy with other sample matrices, dried blood spot samples (n = 63) were obtained and eval

237 6855 (88.1%) of 7782 capillary dried blood spot samples collected were successfully gen

238 g viral load in many countries is to collect dried blood spot samples for testing in regional laborat

239 Dried blood spot samples from mothers and their offsprin

240 Using dried blood spot samples from patients with suspected ma

241 essed and 17 healthy controls) also provided dried blood spot samples from which we assayed interleuk

242 DNA was extracted from the neonatal dried blood spot samples obtained from the Danish Neonat

243 DNA from P. falciparum isolates sourced from dried blood spot samples of 15 asymptomatic malaria case

244 ive untargeted profiles can be obtained from dried blood spot samples that are comparable with whole

245 Dried blood spot samples were collected from HIV-exposed

246 tween April 5, 2007, and Oct 1, 2014, 16 046 dried blood spot samples were sent from 8859 children in

247 via liquid extraction surface analysis from dried blood spot samples, where hemoglobin is highly abu

248 iously been reported for tissue sections and dried blood spot samples.

249 newborns using 30,547 deidentified anonymous dried blood spot samples.

250 es against COVID-19 in human blood serum and dried blood spot samples.

251 is introduced to address the limitations of dried blood spot sampling.

252 With dried blood spots, sensitivity was 92.6% (95% CI 85.4 -

253 tions will facilitate the quality control of dried blood spot sequencing.

254 cability of our method for drug screening on dried blood spots showing excellent linearity (R(2) of 0

255 drolysis of IdS-S by IdS found within a 3 mm dried blood spot specifically produces a nonsulfated pro

256 onstrates the correlation between plasma and dried blood spot specimen citrulline concentrations afte

257 Serum and dried blood spot specimens collected for yaws surveillan

258 protocol to assess resistance using remnant dried blood spot specimens from a representative sample

259 teen FFPET (heart) and blood (whole blood or dried blood spot) specimens underwent targeted next-gene

260 Diet and dried blood spot TC and omega-3 (n-3) index were determi

261 Blood specimens were collected using the dried blood spot technique from 9629 residents (87.6%),

262 n aged 6-59 months in each neighborhood, the dried blood spot technique was used to evaluate immunogl

263 e sample volume restrictions associated with dried-blood-spot technology.

264 Median age at first dried blood spot test was 2.1 (IQR 1.8-2.5) months.

265 808 (67%) individuals with a first negative dried blood spot test, 14 223 (80%) had subsequent dried

266 n untreated infants in Malawi by analysis of dried blood spots tested by nucleic acid silica-bound am

267 ect on adherence, assessed by drug levels in dried blood spots tested monthly for the first 3 months.

268 Early infant diagnosis with dried blood spot testing had high uptake in primary care

269 Early infant diagnosis with dried blood spot testing was provided by the National AI

270 mbination antibody and antigen technologies, dried-blood-spot testing, and self-testing.

271 blood spot test, 14 223 (80%) had subsequent dried blood spot tests, of whom 503 seroconverted after

272 procedure to extract DNA from a portion of a dried blood spot that provides sufficient unamplified ge

273 y blood-smear microscopy and PCR analysis of dried blood spots that had been collected every 2 weeks

274 Dried blood spots that had been stored ambiently for 3 t

275 port, we introduce a 2-tier system using the dried blood spot to first assess CK with follow-up DMD g

276 ting, and uses predetermined levels of CK on dried blood spots to predict DMD gene mutations.

277 The use of dried blood spots to stabilise and ship samples from cli

278 IV status; blood specimens were collected on dried blood spots to test for HIV antibodies, antiretrov

279 This article compares cotinine levels in dried blood spots to those in umbilical cord blood to as

280 CRP was measured using dried blood spots (US) and venous blood samples (England

281 matory markers were measured in eluates from dried blood spots using a bead-based multiplex assay.

282 HIV-1 RNA viral load measurements taken from dried blood spots using a reference panel and field-coll

283 A dried blood spot was collected and used for malaria diag

284 A dried blood spot was collected from each child and teste

285 ive PCR assay with DNA isolated from routine dried blood spots was developed.

286 Glucocerebrosidase enzymatic activity in dried blood spots was measured by a mass spectrometry-ba

287 Cotinine in dried blood spots was measured in 6.35--mm punches by us

288 The most sensitive parameter in dried blood spots was the ratio of receptor/ferritin, wh

289 d on tenofovir diphosphate concentrations in dried blood spots, was evaluated in a nested case-contro

290 ween February, 2014, and March, 2015, 99,243 dried blood spots were analysed and results were availab

291 For genetic testing, dried blood spots were collected and nine variants in fo

292 12-month dried blood spots were collected from 1168 participants

293 Dried blood spots were collected from a pilot subset of

294 Dried blood spots were extracted using a methanolic solu

295 Repeated measures of cotinine in dried blood spots were highly correlated (R(2) = 0.99, P

296 regression revealed that cotinine levels in dried blood spots were slightly lower than those in umbi

297 Tenofovir diphosphate concentrations in dried blood spots were stable and high.

298 disoproxil fumarate, median TFV-DP levels in dried blood spots were ~3-fold lower among patients with

299 lomic pathways and 52 metabolites in newborn dried blood spots, which suggested perturbed tissue neog

300 orrelated (R(2) = 0.99, P < 0.001) among 100 dried blood spots with cotinine quantitated in 2 separat